Designing with Cardboard

TECHNICAL SPECIALISM CARDBOARD CONSTRUCTION IMOGEN LEES JUNE 2013

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CONTENTS PAGE

INITIAL CONCEPTS CARDBOARD AS A STRUCTURAL MATERIAL STRUCTURAL DESIGN DEVELOPMENT CONNECTIONS BETWEEN COMPONENTS WATERPROOFING OF MATERIAL FIRE RATING OF MATERIAL ENVIRONMENTAL STRATEGY

5 19 43 87 111 121 127

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INITIAL CONCEPTS

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DECEPTION

PRIMER EXHIBITION An investigation into how the palette of materials specified for a space can manipulate people’s expectations of it, due to their preconceived perception of the material. These preconceived perceptions are often formulated from past encounters with the material, however what is it about the material that stimulates these feelings.

Our most common initial reaction to materials is whether we like it or not which is usually based on whether we find it to be a comfortable or uncomfortable material.

Looking at our 5 senses (touch, sight, taste, sound and smell) materials obviously stimulate one of more of these to evoke the associated feelings. I believe that touch and sight are the primary senses that would be stimulated by a material with the other 3 being secondary.

Based on this I created two opposing spaces which challenge preconceptions of certain materials with the aim to deceive the participant into thinking there another material. The materials chosen are based on a international survey carried out to investigate what three materials people found comfortable and uncomfortable.

The results of the survey indicated that it is the form and texture so our sight sense that is influenced first when we first approach a material.

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INITIAL IDEAS Following the primer and a separate linked research project I was partaking in, I become interested in the use of paper as a construction material. For the linked research project I made and tested samples of a material called papercrete so that I could get a better understanding of the materials properties before specifying it for a use. Papercrete is made up of concrete, newspaper, sand and water. The newspaper reduces the amount of cement used (the most energy intensive element of concrete) so the material has a reduced carbon footprint. Samples can be seen in the opposite pictures.

MATERIALS WITH A RECYCLED CONTENT

The high percentage of recycled raw material content lead me to think about how Architects specify materials for building construction.

By specifying recycled raw materials it would provide a suitable alternative to the new ‘green’ materials which are currently flooding the market. This is because the finite raw materials are recycled and reused, which reduces carbon emissions as there is no extraction energy required. It also tackles the issue of our raw materials running out.

These images show examples of materials that have been up cycled in their original state into a new building or new type of building material. (middle left) doors (middle right) stone work from the previous building on the site (bottom left) rubber tyres (bottom right) concrete

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OTHER RECYCLED MATERIALS

CEMENT MANUFACTURE

The major environmental impact caused in the manufacturing of concrete blocks derives from the use of cement.

The manufacture of cement is responsible for between 5 – 7% (depending on source) of the world’s carbon dioxide emissions. 40% of the total cement emissions are due to the use of fossil fuels (usually coal) to heat the cement kilns to 1500°C and the remaining 60% is from the transformation of limestone at high temperatures (‘de carbonation’).

RAMMED EARTH

• Rammed earth walls (aka pise) are constructed by the compacting (ramming) of moistened subsoil into place between temporary form work panels. When dried, the result is a dense, hard monolithic wall.

• Rammed earth is an ancient form of construction, usually associated with arid areas. There remain plentiful examples of the form around the world – evidence that rammed earth is a successful and durable way of building. A few historical rammed earth buildings are to be found in the UK. • The likely future for the application of rammed earth is as: - Thermal mass.

- Internal load-bearing unstabilised walls.

- External load-bearing stabilised walls.

• Because of rammed earth’s poor thermal performance, extra insulation will be required.

• Rammed earth is hygroscopic. Wherever walls are clad externally, cladding systems and finishes must be vapourpermeable to allow evaporation. This is important for unstabilised walls, but less-so for stabilised walls where the stabilising agent will impair breathing. Non-the-less, it might be wise to consider vapour permeable solutions for both instances to reduce the chance of condensation build-up on the inside face of insulation.

CONCRETE Reduction in amount of energy use in manufacture

The UK cement industry has reduced the energy used to make Portland cement by almost 25%. In turn, CO2 emissions have been lowered by over three million tonnes, much of which is due to a significant investment in energy efficient technologies, along with the use of alternative fuels and the incorporation of materials such as slag, ash and limestone.

Reduction In Cement

Cement combinations incorporating limestone, fly ash or ground granulated blast-furnace slag can be specified and, in some exposure conditions, may be more appropriate. Embodied impacts are also reduced, for example, cements incorporating 50% slag will reduce the embodied CO2 of concrete by some 40%.

Recycled Reinforcement

UK reinforcement utilises 100% recycled scrap steel sourced from the UK as feedstock. At the end of its life, all reinforcing steel can be recovered, recycled and used again.

Recycled Aggregate

Aggregates, including sand, gravel and crushed rock account for approximately 80% of a typical concrete mix. Here the concrete industry is actively pursuing a policy of recycling concrete in order to reduce the use of these natural resources. Concrete is 100% recyclable and concrete from a demolished building or infrastructure can be crushed and recycled as aggregate for new construction.

High thermal mass

The excellent thermal capacity or thermal mass of concrete enables it to absorb, store and later radiate heat, stabilising the internal temperature of a building. In all buildings, heat is generated by people, electrical equipment, computers, lighting and solar gain which means that buildings can overheat during the summer. Exposed concrete absorbs much of this heat, and can reduce daytime temperatures by up to 4°C or 5°C.

Inherent sustainable benefits

A further sustainable benefit of concrete is its inherent fire resistance and long-term performance. It requires no additional fire protective coverings, chemical preservatives or paint systems that may release Volatile Organic Compounds (VOCs), effecting internal air quality, and which can require ongoing maintenance.

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Future reuse

The flexibility and adaptability of concrete buildings means that when they reach the end of their life they can often be stripped and refurbished to new, contemporary specifications.

CLAY BRICK

Reusable if used with lime mortar Downcyclable into low-grade fill / aggregate Durable Large reserves Un-reclaimable if used with Portland cement mortar High embodied energy High output of CO2 The firing of bricks can produce a bag of pollutants including fluorides, chlorides and oxides of nitrogen and sulphur. Strict limits are placed on emissions in the UK. Clay extraction has a long-term environmental impact on the landscape Transportation can add considerably to the embodied energy

CALCIUM SILICATE BRICKS

Reusable if used with lime mortar

Old bricks can be crushed and recycled into new bricks without loss of quality Durable Large reserves Extraction of sand can cause landscape degradation Transportation can add considerably to the embodied energy

UN FIRED BRICKS

Reusable and recyclable

Very low embodied energy Very low waste Large reserves No emissions during manufacture Can help to regulate humidity Generally non load-bearing Will degrade with prolonged exposure to water Transportation can add considerably to the embodied energy Can place restrictions on internal decoration.

During the same period plant investment went up from ÂŁ119M to ÂŁ167M in 2008 as new more efficient plant was brought online and economies were made in the use of potable water, landfill gas from exhausted pits, reduction of waste to landfill and an increased efficiency of road transport.

WOOD

Where possible it is better to obtain timber from UK sources. The distance timber has to travel from forest to site can dramatically effect its level of embodied energy. The BRE estimates that UK timber can embody as little as 0.52 GJ per tonne, whereas imported timber can embody as much as 7.1 GJ per tonne.

RECLAIMED TIMBER

Using reclaimed timber can be both cheaper and more environmentally friendly than its virgin counterpart. Typical uses are in floorboards and stud work though using reclaimed timber in structural situations is not uncommon. The Salvo website provides listings of reclamation yards region by region. It is usually advisable to allow for long lead times to allow for the contractor to obtain adequate supplies.

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This lead my research to look at materials which are created using a high recycled material content. Apart from the more obvious examples of the reuse of steel and the crushing of concrete up for new aggregate, Cardboard was also mentioned which I had previously come across. It is created from recycled paper which is reprocessed through a paper machine and a cardboard corrugated and could also be classified as a deceptive material as it is often perceived as a weak material. However through the correct design it can be used as a structural material. Precedents show paper being used as a structural material mainly in the form of cardboard tubes and flat panels compiled of layers of cardboard.

Cardboard construction has been used in previous precedents as a successful structural material. It has been used in the form of a tube as well as a constructed panel.

The images show mock ups of how the cardboard has been used in construction so far. (middle) Cardboard used as a composite panel (bottom) Cardboard used as a structural tube

With this I also started to look at materials life cycles and how this could be in

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OPPORTUNITIES OF CARDBOARD • 100% Recyclable material • No virgin raw material used to create it • Reduced fossil fuels and water used for manufacture • Reduces the amount of rubbish sent to landfill • Utilizes some of the 1.3 Million tons of paper/card we recycled this year • Ability to be recycled after use • Can work successfully as a structural, waterproof, fireproof and insulant material

PAPER COLLECTED VIA RECYCLING DEPOTS

LIMITATIONS OF CARDBOARD • Compared to other traditional building materials cost is equivalent due to high manufacture of one off building material • Proposed life span of 20 - 30 years - a generation • Only really suitable for one storey buildings Cardboard can provide an alternative low energy material whose main raw material is recycled and can be further recycled after use. Through analysis of precedents which have utilised cardboard already, research into the structural limits that have already been achieved with cardboard, testing and analysing my own data of cardboards strength I am going to create a building which showcases cardboard as a structural material. As it is not a standardized material in the UK tests would have to be carried out to prove its structural capabilities if it were to be submitted as a material to pass building regulations. This would include its behaviour in an event of a fire and flooding.

This document aims to prove its structural capabilities and follows the developments of the structural design. This is in conjunction with using as many recycled raw materials in all elements of the design and that all the materials can be separated at the end to allow for maximum recycling after designated use.

AFTER 30 YEARS THE CARDBOARD IS RECYCLED BACK TO THE RECYCLING DEPOTS

100% RAW MATERIAL REUSE

PAPER IS PROCESSED IN CARDBOARD MANUFACTURING UNITS

CARDBOARD IS PRODUCED

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EXISTING ALTERNATIVE USES OF CARDBOARD AS A PANEL SYSTEM

HONEYCOMB PANELS Kraft- or aramid-paper honeycomb, used in composite boards, is a well established cardboard building technology. The idea of honeycomb spacing two veneers is familiar from door construction: the same principle is used to build panels for boats, aeroplanes and military vehicles where weight is an important consideration, e.g. the Rutan Voyager [Rutan]. This plane, the first to circumnavigate the globe in a single flight, was made almost exclusively from a 6.35mm sandwich of paper honeycomb and graphite fibre.

GRID CORE ‘Grid core’ is perhaps more appropriate than paper honeycomb. Honeycomb panels are made from recycled fibre sources, e.g. cardboard, or agricultural fibres, e.g. kenaf, rice/wheat straw and oil palm fronds.

The fibres are pulped and moulded as slurry, without resin or binders, into threedimensional structures under extreme heat and pressure which removes the water from the slurry and compacts the particles. The resulting panels have one smooth face with integrated honeycomb ribs. Two panels are then glued rib-to-rib. The manufacturer claims no off-gassing and little pollution during the process. The final product could well be recycled.

However the Grid core systems are an interesting development, using a cardboard honeycomb to give greater strength to a panel. The panels can be supplied up to 75mm thick, cut, painted, edge banded, veneered, and curved to custom radii. The panels can be potentially used for wall, roof and floor elements [Good wood] and have been used in stage sets and furniture. The air trapped in the structure also gives it good thermal insulation properties.

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CERAMIBOARD CeramiBoard速 has good strength, fire resistance and sound transmission qualities.

When added to cardboard it enhances its fire, waterproof and acoustic qualities. It can be described as a cellulosic substrate coated or impregnated with a liquid mix of chemicals, that solidifies and becomes hard on curing.

The process imparts both higher strength and fire resistance to the cellulosic material, and enables products to be made that can be used as building materials. It can be recycled at the end of its useful life, by grinding the product into a powder and blending this powder with the standard chemical mixture when manufacturing new product.

PILE SLEEVES Cardboard tubes are most widely used in the construction industry as pile sleeves and temporary form work for concrete. They can also be used as void formers within concrete to reduce the weight of the material and the amount of amount of material used.

Cardboard tubes are used as form work for concrete, and because of their low price the contractor can afford to pour the columns for a whole floor at once, and then move on more quickly to the next levels. There is also no need to wait to remove the form work from the lower levels until the concrete is fully hardened.

INSULATION Warmcell produce a insulation made of recycled newsprint [Excel]. The product is installed replacing conventional insulation by being blown or sprayed. It achieves U-values of 0.31Wm2K-1 with 90mm thick insulation.

It meets British fire regulations and does not prejudice the fire resistive properties of the wall or roof. It is an established product and has been used in domestic and commercial applications.

Sheets of cardboard could also be used as insulation.

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DELFT LADDER LIFECYCLE DIAGRAM

EXTRACTION OF RAW MATERIALS

MATERIAL CYCLE

PRODUCTION

4.

BUILDING STAGES

BUILDING USE

DESIGN

2.

MAINTENANCE

3.

1.

3.

IMMOBILIZATION

6.

MATERIAL/ELEMENT IMPROVEMENT

USEFUL APPLICATION ENERGY RECOVERY INCINERATION

7.

RECYCLED

DEMOLITION DISMANTLING

INITIATE

5.

8.

9.

10.

1. PREVENTION 2. OBJECT RENOVATION 3. ELEMENT REUSE 4. MATERIAL REUSE 5.USEFUL APPLICATION 6. IMMOBILIZATION WITH USEFUL APPLICATION 7. IMMOBILIZATION 8. INCINERATION WITH ENERGY RECOVERY 9. INCINERATION 10. RECYCLED

DELFT LADDER LIFE-CYCLE MATERIAL FLOWS

The DELFT ladder was devised as a way of representing in a diagram the various possible stages of the life cycle of materials.

It highlights the 10 stages in the life cycle of materials and components specified for a building when a designer can take action to ensure the highest reuse of the materials possible.

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THE CARDBOARD FACTORY LIFECYCLE DIAGRAM

RECYCLING OF RAW MATERIALS

MATERIAL CYCLE

CARDBOARD/PLASTIC MANUFACTURING

CARDBOARD FACTORY

4.

4.

BUILDING STAGES

USE

DESIGN

2.

MAINTENANCE

3.

1.

3.

RESEARCH AND DEVELOPMENT CENTRE

DEMOLITION DISMANTLING

INITIATE

1. PREVENTION 2. OBJECT RENOVATION 3. ELEMENT REUSE 4. MATERIAL REUSE

I have manipulated the diagram to show the CARDBOARD FACTORY LIFE-CYCLE MATERIAL stages atFLOWS which I have thought about the reuse of the material in the design of my building. This involves the use of materials which have been recycled and manufactured into a new material for the main materials for my factory. It also shows in the design of the structure as it has been designed to allow the individual materials to be separated from each other so they can be further recycled at the end of their useful life span. The structure is flexible also so if the size of the building

needs to be altered within the materials initial life span more or less structure can be added rather than demolishing the building and building a new one. The maintenance of the building also thinks about material life cycles as they are powered by renewable sources which are not consuming finite raw materials.

There is also a research and development centre on the site which is continually developing these recycled materials so their life span and structural use can be increased.

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BENEFITS OF RECYCLING RAW MATERIALS

1 TON OF VIRGIN PAPER

One of the main offenders in raw material wastage is the construction industry who according to a recent survey undertaken by the Department of Environment, Transport and Regions (DETR) produce a minimum of 53 million tonnes of construction and demolition waste annually in the UK of which 23 million tonnes of inert waste are not recycled or reclaimed for use.

1 TON OF RECYCLED PAPER

RAW MATERIAL

EXPLOITATION ENERGY

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= 1 Tree

233.3 pounds of C02

= 1,375,000 BTUS of energy

952.2 gallons of water

CARBON EMISSIONS

WATER EXPLOITATION

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CARDBOARD AS A STRUCTURAL MATERIAL

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SHIGERU BAN CARDBOARD TUBE STRUCTURES

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CARDBOARD AS A STRUCTURAL FORM - SHIGERU BAN

PAPER ARBOUR Vertical cardboard tubes capped with a wooden compression ring entire structure capped with a tent fabric roof suspended by a circular framework 330mm in diameter/15mm thick/4000mm high Concrete base, with cantilever

ODAWARA PAVILION Vertical cardboard tubes 530mm in diameter/15mm thick/8000mm high Steel angle joints are post tensioned by steel reinforcement in the tube

PAPER HOUSE Vertical cardboard tubes 280mm in diameter/15mm thick/2700mm high 10 of the paper tubes support the vertical load and 80 interior tubes support the lateral forces, cruciform wood joints in the columns bases are anchored to the foundation on which the paper tubes are fixed by lug screws to act as cantilevers from the floor.

TESTING Compressive strength = 113.9kgf/cm2 Bending strength = 161.3kgf/cm2 1.42 times more than the compressive strength Single shear strength = 581kgf per lag screw

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PAPER CHURCH Vertical cardboard tubes capped by an oval ring around the top 330mm in diameter/15mm thick/5000 high Wooden cruciform for the base, tent like material for the roof

PAPER LOG HOUSE Vertical cardboard tubes 108mm diameter/4mm thick Ridge beam construction - ceiling of tent material – self adhesive waterproof sponge tape between the paper tubes for watertight fit.

NEMUNOKI CHILDREN’S ART MUSEUM 600mm x 150mm x 150mm piece of plywood between two reinforced honeycomb boards which measure 600mm x 1000mm then sandwiched together by aluminium plates to form a 60degree triangle open on one side.

TESTING Tensile strength = 105kgf/cm2 Compressive strength = 94.5kgf/cm2 Full panel bending test = 23.4 kgf/cm2 Tension test adhesion strength between plywood and the skins was greater than = 7.32kgf/cm3 Bearing force of the wood screws = average strength = 290.7kgf

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EAST GATE Rectangular grid shell 150mm in diameter/12.5mm thick TESTING Compression strength of 88kg/cm2 bending strength of 145kg/cm2 – steel tension cables

LIBRARY OF A POET Rectangular grid shell 100mm in diameter/12.5mm thick - Steel tension cables Post tensioned steel wires for spanning sections and to connect wood joints – uses the bookcases as a structural element TESTING Compressive strength = 103.2kgf/cm2 Axial force = 1000kgf Elastic deformation = 0.627mm

HUALIN TEMPORARY ELEMENTARY SCHOOL 6 x 30m footprint

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PAPER DOME Arch rectangular bracing, 290mm diameter/1800mm length lateral tubes of 900mm long 140mm diameter connected by laminated joints Epoxy resin put on the end of the tubes to cap the cut surfaces TESTING Compressive strength – 99.3 kgf/cm2 Bending strength 152 kgf/cm2 more than 1.53 times greater than the compressive strength Moisture test – compressive strength and youngs modulus decreased in an inverse ratio to the rise in moisture content Tensile forces of the structure in the lag screws – 1240kgf strength per lag screw

PAPER ARCH Composed of 8 parallel paper tube trusses laid over a dense grid of tubes intersecting at 45 degree angles Forces of compression set the height of the arch at 9 metres and its radius at 18m

JAPAN PAVILION Grid shell structure is laterally susceptible to wind loads, raised up laterally, strengthened by a timber frame of ladder arches and intersecting rafters – metal joints connecting bracing cables that run diagonally to the paper tube grid 120mm in diameter up to 40m in length TESTING Short term axial Compressive strength = 97.2 kgf/cm3 Short term bending test = 145.2 kgf/cm3 Axial compression test = no irreversible loss in the material strength Torsion test = shear modulus in the coiling direction 140n/mm2

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NOMADIC MUSEUM 64 vertical cardboard tubes, slim steel girders spanning from the outer containers to the inner support columns gave shape to the shed like membrane roof 750mm diameter columns/10,700mm high 300mm diameter triangular a frame on top of coloums/5200mm high On a 6000mm x 5600mm grid The structural loads on the paper tubes can be determined through a straight forward analysis

PAPER-TAINER MUSEUM 750mm diameter poles, roof truss 30 cm paper tubes

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CARDBOARD CATHEDRAL The 90 enormous cardboard tubes will sit between the two steel A-frame end walls, and will be supported by laminated wooden beams. The 700-seat cathedral will stand 23 metres, roughly the height of a six-storey building. The whole lot will be protected by a weathertight poly carbonate roof. Deep concrete foundation. Waterproof polyurethane and flame retardants that the architect has been developing since 1986 – years before environmental friendliness and the use of inexpensive recycled materials were even a concern in architecture.

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CARDBOARD AS A STRUCTURAL FORM - COTTERAL AND VERMULEN

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For Westborough school cardboard was used in a layered panel form as the infill material for a timber stud wall as well as cardboard tubes similar to those used by shigeru ban.

The panel is made up of three layers of 15mm cardboard which was separated by 2mm layer of card. This layer system was to increase the structural capability of the wall as well as reduce water penetration. The form was chosen to reflect paper origami with the folds causing more problems then expected when a mock up was created due to the angle. The angle of the folds were reduced as a result. The pitch of the roof also allowed for optimum rainwater drainage.

The design aimed to use 90% recycled building materials in the overall design. This was not achieved due to the nature of the building, having to be robust as it was a school. Only the cardboard which was 30% of the construction came from a recycled source and was fully recyclable after use.

Interestingly the timber (7%) used in the project was neither recycled from another source or able to be recycled after use.

The concrete used for the foundations and screed (46%) did not come from a recycled source but it is fully recyclable after use. This will probably be in the form of aggregate for more concrete or landscaping. Waterproofing and fire ratings also reduced the amount of recyclable materials but this will be discussed later on.

1. Board Cladding Tile 2. Breather Membrane 3. Aluminium Flashing 4. Aluminium gutter 5. 12mm rigid board to 4mm poly coated Cardboard to 50 x 50mm stud work 6. Cardboard Insulation 7. 9mm pin board to 9mm pin board packing to Cardboard structural panel 8. Cladding 9. Cardboard panels 10. Ventilated void

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TESTING STRUCTURAL CARDBOARD IN COMPRESSION

Having assessed the structures that have already been created out of cardboard I was able to get an understanding of structural cardboard’s properties. The data that I was able to retrieve from other people testing cardboard as a structural material was also essential to my understanding.

Cardboard works best in compression as shown by the structural examples designed

by Shigeru Ban. This property is particularly exploited in the designs which use the vertical cardboard tubes such as the Paper House and the Paper Church. The tubes are fixed to the ground using a cruciform base and then held in compression through a compression ring at the top.

The two main properties which influence the quantity of material used for structural elements are strength and stiffness. I have been able to look at other people’s results from tests carried out to understand these properties for cardboard. However to understand the data better, I have collected my own data about cardboards strength and stiffness. To understand its compressive strength I used a compression testing machine to measure the axial compression loading, which is when the entire material area is in compression. The value that is recorded is the limit of compressive stress that the cardboard can withstand without causing failure to the material. I did this by testing the materials strength and varying the thickness of the tube and the diameter to see how this affects the tube.

The first tube’s dimensions was 170MM: And it recorded a compressive rate of 88 kgf/ cm2

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The figures that I collected have also recorded a bending strength for the cardboard which looks at the materials stiffness. In the figures that I have researched the bending strength is often greater than the compressive strength of the cardboard.

The bending strength measures the limit of the bending stress that the cardboard can withstand whilst it is compression and tension at the same time. The value will depend on either the compressive or tensile strength and whichever is weaker. Once the material has failed as a result of a bending stress it is past it point of elastic deformation and cannot return to its previous material state. The three point test is used to test the bending strength of a material.

TESTING STRUCTURAL CARDBOARD’s BENDING STRENGTH

a

b

LOAD COMPRESSION TENSION

b

a

COMPRESSION

a

FAILURE

TENSION

b

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TESTING STRUCTURAL CARDBOARD IN TENSION

Some of the structural precedents that I have analysed above have used post tensioned steel cable to support the cardboard when it is tension. Steel unlike cardboard works best in tension and fails in compression. In some instances a combination of the two materials is the best solution as they work in harmony with each other by supporting the other material in their weakness.

Steel also is a building material that needs to be recycled as it is made from the finite iron ore natural resource. As it is finite steel needs to be recycled so that we can continue to use it in construction. It is easily recycled through melting and reforming but separating it from other building components such as concrete is often hard. To ensure maximum resectability of building materials the best way to design them is to ensure that they are fully dismantable from each other so they can be separated for their various recycling processes.

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Having looked at the maximum force that the cardboard tubes can carry the effect of creep also needs to be understood. The cardboard tubes similarity to timber is susceptible to visco elastic behaviour or creep. This means that over a prolonged period of time there is an increasing deflection of the material during the application of a fixed amount of load.

Buro Happold engineers carried out research for the Cardboard Classroom in the rate of creep in the cardboard tubes. The results suggest that the cardboard tubes should only be subjected to loads which are 10% of their compressive strength ie creep = 10.0.

TESTING STRUCTURAL CARDBOARD FOR CREEP

They have identified that a portion of the creep was as a direct result of the manufacturing of the tubes as under a compressive axial load the tubes begin to unwind as seen in my tests. They looked at modifying the manufacturing process to see whether they could increase the creep safety factor but it made no difference so the creep partial safety factor remains at 10.0. However for short term loads this factor may reduce, as it was for a separate experiment that they carried out. As parts of the building that I am designed will be subjected to intermittent loading as people walk through the building this is something I need to consider. The wind load which will be experienced on the building will count as a short term load as it will be intermittent.1 1

Westborough school design guide

The final design values that are recommended as a result of the tests carried out to determine cardboards strength and stiffness are:

Limit compressive, tensile and bending stresses to 0.8N/mm2 (FROM 8.1 TIMES) Adopt a youngs modulas value between 1000 and 1500 N/mm2 Limit bending stresses at fixings to 1.4 N/mm2 limit glue shear stress to 0.3 N/mm2 Limit moisture content variation by use of water resistant paper and polyethylene or aluminium foil 1

After finding out these figures in reality a structural engineer would then use them to design the structure. A mock up panel or section would be created to carry out further tests. It is however only through testing the material and pushing it further that it can be developed as a structural material and become a standardized material. The material tests that I have read and processed are based on project-specific tests and particular products. As there are no general structural requirements and standards for cardboard products, the parameters need to be reassessed prior to each new project.

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Cripps, A Cardboard as a construction material Building research and information (May - June 2004) 32 (3) 207-219 spon press taylor and francis group page 209

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ANALYSIS OF PAPER MANUFACTURING

An analysis of how paper is created will help to understand the properties that I have discovered through research and testing.

Paper is a felt of highly compressed cellulose fibres which are formed into a flat sheet through the addition of water and heat. The fibres are suspended in water after being chemically broken down. This pulp which is constructed of 90% water is then sprayed onto a conveyer belt and successively compressed and drained to its final thickness and a water content which is usually 6 - 8%.

As a result of this process 70% of the fibres are aligned to the machine direction, 20% in the opposite direction and 10% in the paper thickness. This creates an anisotrophic material whereby properties are different in the three orthogonal directions, with the bonding of fibres primarily dependent on hydrogen bonds. As most of the fibres are laid in compression the paper has a greater structural strength in compression.

This process method has a 5mm thickness limit due to the ability of the drying process to dry the paper to a sufficient moisture content.

To increase the thickness of the material PVA can be used to glue layers together.

To create cardboard tubes multiple layers of spirally wound paper plies are glued together with a starch or a PVA glue, with up to 22 plies being combined to create a tube of 16mm thickness. It is through the lines of the spiral that the tubes failed in compression as they are the weak points of the material.

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To begin to apply the understanding of cardboards properties from the research, I created cardboard stools. I chose to create stools as even though they are of a lot smaller scale than a building panel the same structural principles apply. I created the stools ensuring that the compressive strength of the cardboard was utilised. I created 3 different stools with each testing a different structural principle.

APPLYING CARDBOARDS STRUCTURAL PRINCIPLES

USING A CONTINUOUS SHEET OF PAPER A piece of paper is not strong when in a flat plane as shown above. However once the paper is folded/fluted its rigidity as a material increases so it can hold more load. This is why sheets of cardboard have a fluted layer of cardboard sandwiched between two pieces of paper, to give it strength. By folding one sheet of cardboard into a stool the strength is perceived to have increased but it simply because the weight is being spread out more so the structure can hold the weight better.

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ANALYSIS OF PAPER IN STRUCTURE

INTERLOCKING RECTANGLE This stool is designed to test cardboard in compression. The top members are submitted to bending stress when weight is applied so they would ultimately fail due to the tensile forces along the bottom chord.

However by interlocking the top pieces with matching bottom pieces the bottom chord is supported in tension. The top pieces also do the same for the bottom pieces.

INTERLOCKING TRIANGLE Similarly to the previous stool this stool is designed to look at cardboard in compression. It is similar to the previous one but the interlocking pieces make triangles instead. This then uses the principle of supporting the cardboard in tension through the interlocking but by also using a shape which is more structurally stable. A triangle will only fail is one point fails where as with a square or rectangle the points can move more freely so the shape is easily deformed.

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Columns Axially loaded columns can be designed from cardboard tubes. Load-bearing columns are generally of a large diameter and the ratio between the tube wall thickness and diameter is high. Hence tubes tend to fail locally in buckling. Overall buckling of the tubes is less likely due to the low slenderness ratio of the sections.

ANALYSIS OF PAPER IN STRUCTURE

Beams Can be designed using sheets of honeycomb cardboard or sections. The support conditions of beams need to be considered carefully to avoid stress concentration and minimise shear deflection and shear creep.

The use of tubes as beam elements is not recommended; their bending capacity is low as the outer surface layer is not continuous.

Walls Flat panels can be used for the design of walls, either load-bearing, self-supporting or mounted to a primary frame. In all cases the stiffness of the wall and its performance under lateral loads are critical. Stiffness can be enhanced by stiffeners, cross walls or by designing the wall as a folded plate. If the panels are mounted on a primary frame, the cardboard acts as a cladding material.

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PAPER AS A STRUCTURAL FORM - DRATZ & DRATZ

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Bales of recycled paper which has been collected and compressed together provides the infill material for this office in Essen by Dratz&Dratz. The building is supported on a steel structure but this shows the insulating properties of paper well. This could be supported inside a timber stud wall also similar to that used in Stock Orchard Street which had straw bale infill. unveil-workspace-made-from-recycled-paper-in-essengermany/

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RECYCLED RAW MATERIALS - STOCK ORCHARD STREET

As part of a studio study visit to London we looked around STOCK ORCHARD STREET

by Sarah Wigglesworth. She has used a wide range of recycled raw materials for the construction of the building, with a different material nearly for each facade. Most of the construction methods she used were developed through working with the builders and trial and error.

The materials chosen were specifically specified due to their limited environmental impact. They were: North facing facade - sand lime and cement filled sand bags South facing facade - Cloth material which is puckered and buttoned to look like a quilt.

The facade is designed to be easily removed so it can be replaced.

East facing accommodation facade - straw bale construction with timber stud work construction and poly carbonate outer facade to act as a rain screen cladding.

The office undercroft - The office is supported on walls made of recycled concrete held in a wire cage. Due to the landfill tax which is now imposed demolished buildings are in abundant and cheap supply.

Environmental strategies - There are two large water tanks which store 3000l of rainwater collected from the office roof, with one providing water for the washing machine and the other for the office toilets.

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41

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DESIGN DEVELOPMENT The design principles that my structure has to work with have been the same from the beginning of my design of my structural system. They are: 1. Needs to use the greatest proportion possible of materials whose raw content has been recycled 2. Structural system needs to allow for dismantling and separating of each material so they can be recycled after use

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SITE CONTEXT

GREAT NORTH COAL FIELD

KILLINGWORTH WAGON WAY

DRY DOCKS DRY DOCKS DRY DOCKS PORT OF TYNE

NEWCASTLE CITY CENTRE

NEWCASTLE 1893 INDUSTRIAL HERITAGE Newcastle established itself as an industrial city due to its income from the coal mines and ship building.

BLYTH

SCIENCE CENTRAL

PORT OF TYNE

NEWCASTLE 2010 MOST SUSTAINABLE CITY IN THE UK Newcastle city council establishes incentives to encourage renewable energy and linked industries to locate to create a new city status.

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O’BRIENS WASTE MANAGEMENT RECYCLING CENTRE

HADRIAN ROAD METRO STATION

WALLSEND DENE RIVER TYNE/WILLINGTON GUT TRIBUTARY COAST TO COAST BIKE ROUTE NORTH TYNESIDE KERB SIDE COLLECTION

1:2500 WALLSEND DENE

1K E

LOCAL CONTEXT WHERE THE RECYCLED MATERIALS WILL BE COLLECTED FROM

NESIDE RESIDENTS TH TY NOR ROM F N TIO EC LL CO E D SI RB

2 RECYCLING SORTED AND PROCESSED AT O’BRIENS WASTE MANAGEMENT CENTRE 1 KERBSIDE COLLECTION

YCLED MATERIALS LIFECYCLE

3 PLASTIC BOTTLES CREAE rPET COMPONENTS AND POLYCARBONATE SHEETING 4 CARDBOARD STRUCTURAL ELEMENTS CREATED IN TEMPORARY FACTORY

CYCLED OF THE RAW MATERIALS USED TO CREATE THE BUILDING ENVELOPE

6 BUILDING DISSEMBLED AND BUILDING PARTS SEPERATED FOR RECYCLING AT O’BRIENS WASTE MANAGEMENT CENTRE

5 CARDBOARD EXTERNAL FACADE CONSTRUCTED

30 YEARS LATER.....

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PHASE 1

As the building is going to be housing a manufacturing unit which will create structural cardboard building components, the use of cardboard in the design is essential. This will then act as a showcase for the material. To highlight the function of the building the first concept was to use the material that each section was utilising so the function would match the facade. For the paper machine the facade would be created out of paper bales stacked on top of each other and held together with a steel grid mesh. For the cardboard machine vertical cardboard tubes would be used using the proportions from the paper church of 330mm in diameter/15mm thick/5000 high.

PAPER

SHARED

CARDBOARD

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The initial sketches show me playing around with the two linear forms within the contoured site. Shigeru Ban didn’t use his cardboard tubes for many rectangular buildings but that doesn’t mean that the vertical tubes can’t be used for this shape. The tubes will have to be kept in compression through the use of a vertical plane.

N

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SITE MA

OPTION 1

The building will be a manufacturing unit for structural cardboard building components which will be created from bales of recycled paper. The machines are long and linear so dictate the shape of the building. The process is intended to be visible to the public so that they can see the paper bales go in at one end and the cardboard tubes come out of the other end. I started to test facades which would allow for combinations of this. Then using models I applied different material solutions to them varying from the use of cardboard tubes, panels of cardboard and paper bales.

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OPTION 2

The material solutions that I have applied to the building facade work with creating a building of 6m high, and 10m in width. These are dimensions that have been achieved by Shigeru Ban in the ODAWARA PAVILION, so I know they are possible. The panel idea is similar to that of the Cotteral and Vermulen CARDBOARD CLASSROOM, with the panels created out of layers of cardboard. The height is taller than that of the CARDBOARD CLASSROOM but through testing I should be able to increase its stiffness. The proposal allows bikes to cycle over the building which will require structural stiffness in the roof.

ODAWARA PAVILION

CARDBOARD CLASSROOM

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LINEAR BUILDINGS

Due to the nature of the building needing to be linear I have looked at a few prececents which are very long linear buildings. This is to get an idea about the impact of the building on the surrounding landscape as well as how I deal with the approach to the building by the public. This precedent is the XX and is on a flat landscape. The building is very dominant as the landscape is so flat. The linearity is continuous with no break at all but this increases the impact of the building. It has a pitched roof which breaks up the facade and makes it more interesting than just a flat roof.

The pitched roof also allows a good amount of sunlight to get into the space.

Attempting to put my building into a contoured site

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This precedent is the new Vicker’s building

by Ryder in Scotswood, Newcastle Upon Tyne. I have also chosen to look at this precedent due to its linearity and its proximity to the river. The building is not perpendicular to the river bank so it creates varying sized spaces between the building and the river bank. This looks as though it is a service yard though. The linearity of the building is punctured by an entrance building half way along. This maybe so that visitors do not have to walk the whole length of the building to enter the building from either direction. The facade is continuous plane with the roof so rainwater flows through the channels and down the front of the facade.

V on the front facade then channel the water down to ground level.

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PHASE 2

Having researched further the size of a paper machine and the space needed to service it, I had to move the building to a different site.

It also needs to be positioned on a very flat surface which the contours on the previous site would not of allowed. The shape and size of the machine (100m in length, 10 m in width and 18m in height) dictate the shape of the building. As I want to make cardboard I also need a cardboard machine which is another 60m in length, 10m in width and 8m in height.

The process will work best as a continuous production so a building which is long and linear will suit it best. This means it will have to be about 250m in length, 20m in width and 20m in height. The height of the building will be the greatest test on the cardboard. Similar heights have been achieved by Shigeru Ban in the PAPER-TAINER MUSEUM, NOMADIC MUSEUM and the CARDBOARD CATHEDRAL.

SERVICE ACCESS B

CARDBOARD COMPONANTS EXPORTED VIA THE RIVER TYNE

+ 4M pedestrian entrance

CARDBOARD MACHINE

PAPER MACHINE

PAPER ROLL STORAGE A

+ 0M cyclist entrance

B

RECYCLED PAPER TRANSPORTED FROM RECYCLING CENTRE TO FACTORY VIA CRANE

1:200 SITE PLAN

N

RESEARCH AND DEVELOPMENT CARDBOARD MACHINE

RESEARCH AND DEVELOPMENT

PAPER MACHINE

CAFE

+ 4M pedestrian entrance PAPER ROLL STORAGE

1:200 SECTION A - A

N

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+ 0M cyclist entrance

These are some of the largest spanned buildings that Shigeru Ban has designed. To cope with the height he has triangulated the top element of the structure for the PAPERTAINER museum and nomadic museum and the whole structure for the cardboard cathedral. The cardboard tubes are set out on a 6000mm grid in the two museums but the tubes are 750mm diameter. This will obviously take up a lot of floor space.

(top) PAPER-TAINER museum (middle) nomadic museum (bottom) cardboard cathedral

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These development sketches show developed of the form of the main entrance canopy for the building. As the building is developing cardboard as a structural material it is desirable that the facade is able to be adapted to show these developments. The entrance canopy for the main building would be the most desirable part for this adaptation to take place. The public would enter the building through poly carbonate enclosed tunnels so they could still enter the building when the construction was happening. These sketches show my ideas of the form this canopy could take. They are inspired from looking at the structural precedents.

I looked at the paper dome and the arch as they showcase cardboard in an unusual way.

The archway would also be a good contrast to the linearity of the rest of the building and make it obvious to where the entrance of the building was. The height of the paper dome also reaches 9m which shows that it would be realistic to reach the height that I would need it too. I also looked at the paper church which spaced the linear cardboard tubes apart to make it obvious where the entrance to the building was. The height of these tubes is also 5000mm which would be a suitable height for my building too. (top) paper dome (middle) paper church (bottom) paper arch

PAPER DOME SHIGERU BAN

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The canopy would show an exhibit of the work that the research and development team had developed. As with the rest of the building the components need to be fully dismantable for ease of putting up and down so that once the canopy is finished with it can be erected somewhere else.

PAPER ARCH SHIGERU BAN

PAPER CHURCH - SHIGERU BAN

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PHASE 3

STRUCTURAL FACADE To be able to create the height and width I need for the building I initially looked at using vertical cardboard tubes similar to that of the Shigeru Ban paper house. It would have a pitched roof to make it look less like a cardboard box and to allow the rainwater to drain. The roof would be supported by internal columns using the dimensions used in the NOMADIC MUSEUM. The use of the triangle at the top of the internal columns is similar to the stool that I created out of triangles. The use of the triangular shape gives the structure more rigidity. This is because the triangle only falls apart if it fails at one point. Where as with a rectangular structural shape it can move around more points. The axo shows the primary structure of columns of 750mm diameter on a 6m grid with 300mm diameter triangles connected on top and secondary structure of 300mm diameter vertical cardboard tubes.

TUBES IN COMPRESSION

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GLAZED FACADE To try and showcase other properties of cardboard I looked at the structural frame used in LIBRARY OF A POET, which is a more open structure. This would allow for the incorporation of glazing into the frame and could be used at points in the facade to break up the vertical cardboard tubes. This structure would be used in the entrance spaces to make it obvious where the public should enter the building.

500mm

100mm 100mm

CARDBOARD TUBE

CARDBOARD TUBE

STEEL TENSION CABLES

TIMBER JOINTS 500mm

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PHASE 4

MAIN ACCESS TO SITE UNDER EXISTING BRIDGE

ACCESS

MAIN ACCESS FOR PEDESTRIANS

BIKE RAMP

CLUB HOUSE FOR MARINA

RAMP LEADING TO PAPER MILL CAFE OUTDOOR EXHIBITION AREA

KITCHEN

PAPER STORE

INTERNAL EXHIBITION AREA

BIKE RENTAL AND REPAIR

PAPER MILL

ACCESS TO CPD WORKSHOP AREA

MAIN ACCESS TO SITE UNDER EXISTING BRIDGE

MAIN ACCESS FOR PEDESTRIANS

BIKE RAMP

CLUB HOUSE FOR MARINA

CRANE

INTERNAL STEEL FRAME Having done more research into the paper machine I have discovered that for the paper machine to function it needs to have a crane which runs the length of the machine to move the steel and paper rolls onto different sections of the machine. This means that I will have to have a steel or concrete frame for the paper machine to be located in. I can’t use cardboard as the forces of the crane and industrial processes mean I can’t use a material which is susceptible to shear and tearing which cardboard is. I will use a steel frame as steel is easier to be recycled compared with concrete.

Steel also works well in tension so I can use it to support the cardboard in tension where it is weaker.

RAMP LEADING TO PAPER MILL

OUTDOOR EXHIBITION AREA

INTERNAL EXHIBITION AREA

PAPER MILL

ACCESS TO CPD WORKSHOP AREA

Forces on a rectangle

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Forces on a triangle

STRUCTURAL FACADE As there will be a steel frame internally I will use the cardboard to provide a cladding or wrap for the building, which will also support the ramp which will run the length of the building so that the visitors can look at the paper and cardboard machine. Looking at the previous structure which is now redundant as I need an internal steel frame, I want to further explore what using a triangular A-frame would allow me to do. A triangle as shown in the diagram is the strongest shape because when it is subjected to large forces it only failures as a result of cardboard fatigue rather than geometric deformation. If a force is applied to one point of a triangle it will not move where as with a square or rectangle it will distort to a parallelogram.

TRIANGULAR A FRAME DEVELOPMENT Through utilising structural triangles it would allow me to get the height that I require for my building and could potentially give me greater scope for a more interesting facade. The sketches show this development.

These sketches show an a frame running across the floor plan with the ramp spanning through the a frames. Bracing would be also needed to span between each a frame to triangulate the space as without it would be rectangular. By having the ramp spanning between the a frames in this direction it would not work as the width of the ramp will reduce as it gets higher, as the width of the a frame reduces.

Here I have looked at varying the widths of the alternating a frames to make a more interesting facade and different spaces inside. However the same problem with the ramp will occur as it is still in the same orientation as the other design.

I have turned the a frames around so that they run the length of the facade rather than perpendicular to it. By rotating every alternate triangle I can create a frames which will be self supporting and maintain its shape. I have also looked at then putting pods on the front of the a frame to increase the floor space.

Development of this idea follows on.

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18000mm

Having explored how a triangular a frame could provide the structural strength that I require I have designed the main facade.

The components which I have designed to hold the cardboard members together will be discussed later on. The facade is constructed out of an a frame which runs horizontally down the length of the building.

The triangles are rotated so they fit together to form something which looks almost like a truss. The dimensions of an individual frame are shown in the diagram with the structural cardboard tubes being 300mm in diameter.

For the first test I have used an infill material of horizontal 100mm diameter cardboard tubes. This will also improve the lateral strength of the triangles.

6000mm

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To increase the a frames stability, make the facade look more interesting and provide extra floor space needed for the ramp I looked at adding triangular pods which are created using the same proportions of the a frame which runs the length of the building.

The pods will run the length of the building and increase the stability of the facade. They will allow the ramp to expand at specific spaces so that the visitors can pause and look at the machine and groups can have educational talks. The shape also starts to have a dialogue with the external space creating pockets of enclosed sheltered space on the outside.

1:10

1:50

1:20

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In phase 3 I talked about wanting to showcase cardboard’s structural possibilities in as many different ways as possible. I looked at the LIBRARY OF A POET as the main precedent as it allowed for the most glazing. Other precedents which allow a lot of glazing is the JAPANESE PAVILION (see below) and the NEMUNOKI CHILDREN’S ART MUSEUM. They both use triangulation to create these windows to ensure that the facade is still structural. I have applied the detail which is used in both of these precedents to one of the a frames. This structural bay would then be used at the points in the building where the public enter as it would show a variation in the facade indicating a different function of the building.

The detail is shown later on.

1:50

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Having discussed the structural capabilities of the a frame with triangular pods with the structural engineer, the design was agreed.

From his previous knowledge of working with cardboard he believed that cardboard would be able to provide the necessary structural support using the dimensions that I have used. As I know that the pods will work I am able to push them further and start altering their shape and size to make the facade more interesting and provide the spaces that I need. With the triangular pods added to the structural frame it begins to resemble a piece of folded paper. To look at the types of spaces that I could potentially create, I started to fold pieces of paper up for inspiration. This was helpful as it allowed me to think about the pods in 3d as a 2d drawing was hard to get the point across with.

PHASE 5

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Looking back at the westborough school precedent that I initially looked at the design is also based on the folding of origami shapes. The roof also has a similar shape which is designed to aid water run off for grey water collection. The folds however do not pitch at the top as the design I am looking into will. Looking at the design guide which I have had access too they originally designed more complicated pitches between the panels but had to reduce the angle as the joining was too hard.

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The following pages show my development following this experiment of the facade and the roof shapes.

For this idea I have rotated the entrance triangular pods to make a more obvious entrance space and more of a human scale.

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For this option I have rotated every triangular pod to make it look like a wave. The detailing for this would make the building to hard to be altered by the architects.

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Here I have gone for a more regular grid for the main facade with all the triangular pods being the same dimensions. For the entrance modules I have reduced the height of the triangular pods to make them more of a human scale and more obvious where the entrance is.

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Here I have looked at alternating the dimensions of the alternate triangular pods and having a few larger pods which could accommodate more people for a longer period of time.

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Here I have looked at having a more simple facade with the triangular pods being the same dimensions with a few larger pods to accommodate more people for longer periods of time.

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CRANE TO TRANSPORT PLASTIC COMPONANTS TO ASSEMBLY LINE

CRANE TO TRANSPORT PAPER BALES INTO THE MACHINE

VIEWING POINT

UNDER ROAD BRIDGE ACCESS

ACCESS CORRIDOR FOR PUBLIC TO USE PAPER ROLL STORAGE

EXHIBTION SPACE

BIKE RENTAL /REPAIR

CAFE

DOCK

RAMP

SERVICE ENTRANCE BACK ENTRANCE TO SERVICE PAPER MACHINE

SERVICE ENTRANCE

OUTDOOR MATERIAL TESTING AND BUILDING

ACCESS ROAD 1:200 GROUND PLAN

SERVICE ENTRANCE

N

Thinking about how these experiments would work structurally and ensuring the structure allowed for a panel to be altered independently from the rest of the structure I went for a more simple structural layout which maximised the repeating elements. Each bay of the roof would be a repeating element with the facade panels varying depending on the activity they held. By altering the facade pods dimensions it meant that from the outside the visitors could gauge what happened at the different sections of the building. This is important due to the length of the building so that visitors were able to go to the section that they wanted to rather than having to walk a long way round. The bigger pods indicated BIKE RENTAL /REPAIR that there was a platform on the ramp at that CAFE point as there is an interesting part of the paper machine there, so the visitors could head straight to that part of the machine if they wanted too. The pods which did not contain platforms would not be redundant but provide ventilation and lighting for the ramp.

This is discussed later on.

OUTDOOR MATERIAL TESTI

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PHASE 6

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Following my crit I have further developed the structure with a regular repeating grid. I have designed the components which will be made out of recycled plastic bottles but these will be discussed later on. I have started to look at the angles of the cardboard tubes for the facade and then how they will connect to the roof. The angles used for the cardboard tubes will ensure that triangulation of the elements is kept. I have also started to develop the saw tooth roof detail in section. This will allow for north light to come into the factory and solar panels to be on the side facing side. It will also help with the water drainage off the roof so that it can be collected for recycling.

Following another structural tutorial the dimensions were finalised and the component jointing discussed. The roof design was highlighted as it had not been discussed before. As the inner steel frame has to stay due to cardboard’s weakness in shear force I wanted it to do more than just support the crane. I wanted it to support the cardboard in a way that would allow me to do more with it.

The truss which will support the roof was finalised with a steel bottom chord for the truss. This is to allow for a span of 18m as the steel takes the tension force. The design that I have shown maximises cardboards use in compression and how I have then used steel for the structure that is in tension. I have also used it for the industrial section of the design as it will be getting lots of pattern loading from the crane and a lot of stress on joints which the cardboard will not be able to cope with.

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SAW TOOTH ROOF DESIGN Sketch of the roof design plan showing the plan of the steel design.

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LOADING DIAGRAM

WIND LOAD FORCE DIAGRAM Wind load force pushed Leward section up but it is tied down by the a frame vertical and the load is transferred through the roof truss to the other side. Here the opposite happens.

The connections tie the structure to the ground.

INTERNAL LOAD FORCE DIAGRAM Paper machine loads supported by the inner steel frame horizontally through the floor plate and then vertically down through the steel frame. Roof load is transferred through the roof trusses and then down vertically through the cardboard structure. The ramp is also supported in this way.

LOAD TRANSFER

PUSHING UP WIND LOAD

PUSHING DOWN

A FRAME TAKES THE LOAD

LOAD TRANSFER

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RECONFIGURING THE SECTION

most up to date section

76

MANIPULATING THE FACADE

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FINAL DESIGN - EXPLODED AXO NO METRIC OF STRUCTURAL GRID

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A FRAME CARDBOARD TUBES

CARDBOARD TUBES TRIANGULAR PODS

These exploded details highlight the ability for the structure that I have designed to be dismantled as required in the DELFT ladder diagram so that it can either be reused in another location or the materials separated from each other for individual recycling into another building component.

HORIZONTAL TUBES FOR SOLAR SCREENING

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1:50 SECTION

First glimpse by the visitors of the scale of the paper machine inside its cardboard envelope.

THE PAPER MACHINE HALL

FIRST GLIMPSE BY THE VISITORS OF THE SCALE OF THE PAPER MACHINE INSIDE ITS CARDBOARD ENVELOPE

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Cardboard is the main material that will be used in the structure but the rest of the building material palette is made up of materials with a recycled content. This was one of the project aims that was stated at the beginning. By specifying these materials I am ensuring that there is a reduction in the amount of resources (water, electricity), carbon emissions, and raw materials used in their recycling into a new use compared with creating the materials from scratch.

1:20 SECTIONAL MODEL THROUGH TRIANGULAR POD 15

11

3

14

3 3 17

16 11

10

10 6

9

1. rPET Base Component 1 2. rPET Base Component 2 3. 300mm diameter Cardboard tube 4. 300mm diameter steel column internal structure for paper crane 5. 100mm perforated metal grid 6. rPET cross ramp structure component 7. 100mm diameter horizontal cardboard tubes 8. 40mm poly carbonate waterproof covering 9. 150mm perforated metal grid for ramp 10. 40mm poly carbonate balustrade 11. rPET Top Component 3 12. rPET Top Component 4 13. rPET Top Component 5 14. rPET Top Component 6 15. 300mm Steel beam 16. 100mm diameter cardboard tube truss 17. 40mm poly carbonate waterproof covering

12 13

7 8

6

10

3 5 2 3

3 4 1

2 3

2

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RECYCLED MATERIALS PALETTE

1. CARDBOARD

2. rPET

STRUCTURAL CARDBOARD TUBES

STRUCTURAL COMPONENTS

WATERPROOF FACADE/INTERNAL ENVELOPE

3. POLY CARBONATE

4. STEEL

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INTERNAL STRUCTURE FOR PAPER MACHINE CRANE

To highlight the potentials of utilising recycled waste materials in the building the above diagram highlights the waste materials that I have used, what materials I have created from them and where they are used in the building.

Through this reuse I am highlighting the potentials of using waste materials in a way that most people would not think possible as the materials would not look aesthetically pleasing or be structurally stable. I am challenging peoples perceptions of waste by using these materials in prominent positions in the building and landscape.

5. RUBBER BARK

6. WOOD CHIPS

7. CONCRETE AGGREGATE

8. PAPER CRETE

WILDFLOWER FLOWER BEDS

MEANDERING PATHWAY

WILDFLOWER FLOWER BEDS

INTERNAL FLOOR/EXTERNAL PATHWAYS

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CONCRETE PILE FOUNDATIONS

The building will require piling throughout the site due to the weight of the paper and cardboard machines. As the site is already a brown field site there is a concrete slab already laid. This however will not be suitable as the paper machine requires it to be completely level so a new one needs to be laid. The slab will be made by crushing up the former concrete slab and using it as aggregate for the new slab. This is one of the few opportunities that concrete has to be recycled. It can also be used in gabion to create natural structural walls. These will be used in the landscaping of the project.

Concrete has a long life span so its high energy intensity needed for its creation can be slightly offset by this. As the slab will be flat and thick it will also be suitable for most uses once the paper machine has gone so it can support a new building if needed.

The foundations will be piled throughout the site under the main structural grid as shown in the layout plan. As some of the structural members for the pods will be able to move they will have pad concrete foundations underneath them as they won’t have to support too much load as the structure is not heavy.

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1:200 site section showing the pile foundations 600mm diameter needed to support the weight of the paper machine.

1

2

8

3 4

6

5

9

1:25 GROUND SLAB DETAIL 1 300MM DIAMETER CARDBOARD TUBE 2 100MM PAPERCRETE SCREED 3 75MM NEWSPAPER INSULATION 4 300TH CONCRETE SLAB 5 20MM COMPRESSIBLE BOARD TO ALLOW MOVEMENT 6 DRAIN PIPE 7 40MM POLYCARBONATE COVERING 8 DRAINAGE CHANNEL 9 UNDERGROUND PIPES CONNECTED LEADING TO MAIN WATER STORAGE TANK

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CONNECTION MEMBERS

The cardboard tubes connections will not be able to be created out of cardboard at the moment. This does not mean that the research and development centre which is part of the building will not be able to design one in the future. The main objective of the components is to ensure that the fixing is not permanent and that it allows the structure to be able to be dismantled at the end of the design. This dismantling is so that parts of the building can be replaced when required without taking down the whole building, so that it can be reused at another location if

it is not at the end of its usable life, and so that the materials can be separated from each other at the end of their usable life and recycled. The materials that the components are made from need to be from a recycled source which can be recycled after use as well. Shigeru Ban uses mainly timber and steel for his joints due to their recyclable nature and structural capabilities. The connections are temporarily bonded together with bolts rather than welding or gluing.

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COMPONENT ANALYSIS - CARDBOARD TUBE CONNECTIONS/FOUNDATION

1

2

3

1. 55MM DIAMETER 1890MM LENGTH CARDBOARD TUBE 2. PLASTIC JOINT 3. PLASTIC ANCHOR

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EMERGENCY SHELTER The components for this design are made out of plastic. This is so that they are lightweight, cheap and durable as the shelter is very temporary. It also allows for the correct angle to be created for the paper tubes to be held in a tensioned triangle. The plastic also goes into the ground so needs to a waterproof material which will hold its shape when wet and not rust or corrode. The plastic can then be recycled or reused when this life span is over. The plastic

COMPONENT ANALYSIS - CARDBOARD TUBE CONNECTIONS

LIBRARY OF A POET This was the first permanent building made from paper tubes and the first to use timber joints. A post tensioned steel rod is used to connect the wood joints which are 10cm squared pieces of timber. The timber is designed so that the post tensioned rods can pass through the joints and be secured on the opposite side. The timber is the same width as the cardboard tubes.

1. POST TENSIONED STEEL ROD 2. 100MM OUTSIDE DIAMETER/87.5MM INSIDE DIAMETER CARDBOARD TUBE 3. 100 CM CUBED TIMBER JOINT 4. POST TENSIONED STEEL ROD

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COMPONENT ANALYSIS - FOUNDATION DETAIL

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2

3

4

5

6

1. 280 MM OUTSIDE DIAMETER/250MM INNER DIAMETER CARDBOARD TUBE 2. 75 MM LENGTH STEEL ROD 3. 12MM INDUSTRIAL PLYWOOD

7

4. 306 MM INDUSTRIAL PLYWOOD CRUCIFORM 5. 12MM LAG SCREW 6. 12MM INDUSTRIAL PLYWOOD 7. 16MM INDUSTRIAL PLYWOOD

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PAPER HOUSE The vertical cardboard tube is held in compression and preventing from bending due to the cruciform base that fits inside of it. The cruciform is made from plywood and then attached to 1 other thinner disks of plywood with a 12mm steel threaded rod which runs through the cruciform. The vertical cardboard tube is held in place using 18 lag screws which connect through to the plywood cruciform. The fixing allows for complete dismantlability of the structure.

TESTING Shear tests between the cardboard tube and paper which are held together with steel lag screws with the single shear strength was 581kgf per lag screw.

COMPONENT ANALYSIS - FOUNDATION DETAIL

1

2

3

4

5 NOMADIC MUSEUM The vertical cardboard tube is held in compression and preventing from bending due to the cruciform base that fits inside of it.

The cruciform is made from plywood and then attached to 5 other thinner disks of plywood with a 12mm steel threaded rod. This threaded rod then connects to a steel I beam which acts as the foundation as the structure is temporary. The vertical cardboard tube is held in place using 16 lag screws which connect through to the plywood cruciform.

The fixing allows for complete dismantlability of the structure.

1. 280 MM OUTSIDE DIAMETER/250MM INNER DIAMETER CARDBOARD TUBE 2. 12 MM SCREWS 3. 30 MM INDUSTRIAL PLYWOOD

6

CRUCIFORM 4. 12MM INDUSTRIAL PLYWOOD 5. 60MM 12MM DIAMETER THREADED ROD 6. 12MM INDUSTRIAL PLYWOOD

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NOMADIC MUSEUM TUBE CONNECTIONS The cardboard tubes are connected together using steel plates which are connected to plywood circular stoppers which are inserted in the top of the tubes and fixed in the same way that the foundation components are.

The steel plates overlap so that they can be connected together with a nut and bolt to allow for easy dissemble. This also allows them to be held in a triangle which as discuss before is the most stable shape and allows for bigger heights to be achieved.

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Shigeru Ban in the above examples has used cruciform for his foundation details where the cruciform is inserted inside of the tube.

He uses this form for the buildings which he has used the tubes of the greatest height so which are at the greatest risk of bending. This is because the cruciform stops the tube form being able to bend in either direction as the shapes stops this from happening. This idea is going to be the best way to ensure that the cardboard tubes do not bend as they will be very long lengths and at risk of this.

CRUCIFORM CONNECTION MEMBER

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PHASE 1/2

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For the first design I considered using bales of recycled paper stacked for the paper machine and vertical cardboard tubes for the cardboard machine. The paper bales would be held together inside a timber stud wall with a spike running through them similar to the straw bale wall in STOCK ORCHARD STREET. The vertical tubes would have the same foundation detail as the PAPER HOUSE and be held in a compression ring.

For phase 3 I was looking at continuing to have vertical cardboard tubes running the length of the machine. The roof would be pitched to allow rain to run off which would be supported by a row of columns that are on a 6m grid which run the length of the building similar to that in the NOMADIC MUSEUM. The vertical cardboard columns will have a base constructed using the cruciform to ensure that the cardboard tube doesn’t bend in either direction as discussed above. These components will also allow the building to be dismantled easily so that the materials can be recycled separately.

PHASE 3

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To try and incorporate glazing into my design in parts of the building where the public are I looked at LIBRARY OF A POET which allows for larger voids in the facade as it is based on a space frame. By using this structure for the glazed areas it will allow me to make a distinction between the two spaces as well. It will also allow a lot of light in which is needed more for the public areas of the building.

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Having changed my design to the structural A Frames I need to think about the best way to connect all of these elements together, to the top bracing element along the roof and to the foundation. I have looked again at the NOMADIC MUSEUM and how it has the connections embedded in the top of the columns so they are easily dismantable from each other. There is also a connection which connects directly to the roof to allow for the transfer of the roof loads. Using this information I have designed concessions which also can be embedded in the top which will allow the tubes to be connected to the linear element.

PHASE 4

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1:10

TOP ELEMENT

FOUNDATION

ELEVATION OF TOP DETAIL

1:10

For this idea the three cardboard columns have separate connecting elements which join separately to the horizontal element which runs the length of the facade. They are connected with a bolt so they can be dismantled. The same applies to the foundation.

1:50 1:50

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1:10

FOUNDATION

TOP ELEMENT

ELEVATION OF TOP DETAIL

1:10

For this idea the three cardboard columns connection joins together through a continuous sheet of plywood which ties them together. They then have one steel element which comes out of the top and connects the horizontal element. The foundation detail is the same as the other example.

1:50

1:50

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I have also started to think about how the smaller cardboard tubes connect to the larger ones to form the facade detail. The horizontal tubes provide a cladding system which will act as a rain screen cladding. They will be connected to the larger tubes through a steel detail which clamps around the tubes at the end as shown in the detail.

1:20

100

The components that I designed for phase 4 would not work well for the height of the tubes that I want to make. Looking back properly at how Shigeru Ban supported the tall columns it was through the use of the cruciform shapes which stopped the tubes from bending in both directions. The cruciform is the important part of the previous components which stops the cardboard tubes from bending. This idea needs to be bought into the a frames to stop them from bending.

PHASE 5

I have now designed different components based on the cruciform used in the NOMADIC MUSEUM and the PAPER HOUSE. There will have to be a few different types of components based on the same design to allow the cardboard tubes to be held at different angles to support the triangular pods and the a frame. The components will be able to interlock into each other so various formations can be created.

To begin to understand how many cardboard tube elements would go into each component I made a rough model out of straws to understand how many elements I need to accommodate.

(bottom) cruciform base used for the NOMADIC MUSEUM

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NTS rPET JOINING COMPONANT WITH 7 CARDBOARD TUBES JOINING

1:50 FRO

NTS STEEL COMPONANT TO SUPPORT RAMP

1:50 PLA

NTS STRUCTURAL AXO

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NTS FRONT ELEVATION OF rPET JOINING COMPONANT

For this design the main component has 7 cardboard elements joining it so it is quite big. The steel which spans the roof also joins into the back of it. Part of the component has to be angled to allow the triangular pods to be created. There is a smaller component which is featured at the top of the triangular pods which is a smaller variation of the bigger one. I have also started to look at how the ramp will be supported off the cardboard a frame. This will be a steel ring which goes around the cardboard tube which will have a cruciform attached to support the horizontal tube.

NTS rPET JOINING COMPONANT WITH 7 CARDBOARD TUBES JOINING

1:50 FRONT ELEVATION

NTS STEEL COMPONANT TO SUPPORT RAMP

1:50 PLAN

NTS FRONT ELEVATION OF rPET JOINING COMPONANT

NTS PLAN OF rPET JOINING COMPONANT

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PHASE 6

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This redesign is just an bit of a re configure of the previous design based on a change to the structural a frames. There are 10 different components in total with a few being rotated so are based on the same design. They are all made from rPET and created in the factory across the shore from the factory. They have the cruciform shape as discussed before and will have the cardboard tubes fixed to them using bolts which are easily removed and a non permanent joint. I have drawn exploded axonometrics of each one to show how they are able to be dismantled. I have also modelled them at 1:20 and 1:2 for my final models as they are very hard to draw effectively.

A - ROOF TRUSS CONNECTOR

1 rPET CONNECTOR 2 300MM STEEL BEAM 3 300MM/15MM DIAMETER CARDBOARD TUBE 4 300MM STEEL BEAM

2 3 4 1

C - FACADE HORIZONTAL BRACING CONNECTORS 1 300MM/15MM DIAMETER CARDBOARD TUBE 2 120MM rPET CONNECTORS 3 100MM/7MM CARDBOARD TUBES

1

2 3

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B - TOP OF PODS CONNECTOR 1 AND 2 1 rPET CONNECTOR 2 300MM/15MM DIAMETER CARDBOARD TUBE 3 300MM/15MM DIAMETER CARDBOARD TUBE 4 300MM/15MM DIAMETER CARDBOARD TUBE 5 rPET CONNECTOR 6 300MM/15MM DIAMETER CARDBOARD TUBE

2

1

4

3

5

7 5

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D - INTERNAL RAMP SUPPORT CONNECTORS 1 300MM/15MM DIAMETER CARDBOARD TUBE 2 300MM/15MM DIAMETER CARDBOARD TUBE 3 310MM rPET CONNECTORS 4 100MM/7MM DIAMETER CARDBOARD TUBE 5 300MM STEEL COLUMN

1 2

4

3

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E - BASE OF A FRAME/ TOP OF A FRAME 1 300MM/15MM DIAMETER CARDBOARD TUBE 2 300MM/15MM DIAMETER CARDBOARD TUBE 3 rPET CONNECTOR 4 300MM/15MM DIAMETER CARDBOARD TUBE 5 300MM/15MM DIAMETER CARDBOARD TUBE 6 rPET CONNECTOR 7 BOLTS TO FIX TO CONCRETE GROUND SLAB

4

2 1

3

6

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WATERPROOFING

As cardboard becomes a pulp when wetted, it is imperative that all necessary steps are taken to prevent water ingress into the cardboard elements. Untreated card is also hygroscopic, meaning that it will absorb moisture from the air, and in moist air this can lead to the collapse of the material. There are various approaches to waterproofing a cardboard building shown by the precedents that I will discuss. For this project though to ensure that the brief is adhered too I need to ensure that the

approach used still allows the cardboard to be recycled at the end of its life span and that it can be dismantable.

Water

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WESTBOUROUGH SCHOOL

In the Westborough project a three step approach to water protection for the card panels was taken.

Step 1: Treated card The first level of “protection� is in the use of water-resistant cardboard. An additive was used which renders the board water-resistant but can be removed on re-pulping.

Some treatments are likely to be changing the material to such an extent that it is not really cardboard and will no longer be recyclable.

Step 2: Coating A further level of protection can include applying an external coating such as a polymeric coating after manufacture of the element; building paper applied after erection; or aluminium foil applied as part of the manufacturing process.

In the Westborough building a poly-coated layer on the inside was used, and a building paper on the outside. This reflects normal practice for timber framed buildings where the main source of moisture is the warm moist air on the inside generated by the occupants and their activities. There is a vapour barrier on the inside, but a breathable water barrier on the outside face. This minimises the flow of water vapour into the card, but allows it to escape if any does collect in the card.

Step 3: Over-cladding Although a coating layer will be waterproof when it is first installed, it will be vulnerable to moisture if it becomes damaged. On the inside there is an extra 1 mm layer of board after the vapour barrier to physically protect it from scratching. We also provided pin board zones to protect the wall from drawing pins!

On the outside over-cladding was used in a material as close to cardboard as we could manage. This is a wood fibre and cement panel product (sasmox) which provides water and fire protection for the card panels underneath, and is partly recyclable.1

1

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Richard Hennessy email buro happold

1. Board Cladding Tile 2. Breather Membrane 3. Aluminium Flashing 4. Aluminium gutter 5. 12mm rigid board to 4mm poly coated Cardboard to 50 x 50mm stud work 6. Cardboard Insulation 7. 9mm pin board to 9mm pin board packing to Cardboard structural panel 8. Cladding 9. Cardboard panels 10. Ventilated void

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SHIGERU BAN

Although Shigeru Ban uses cardboard for his structure its waterproofing strategy does not need to be as sufficient as Westborough school as the structure is usually behind a rainscreen cladding. The claddings used vary from 5 layer pvc and paper membrane in the Japan Pavilion, glazing in the Library of a poet and shipping containers in the NOMADIC MUSEUM. The tubes are however still waterproofed using a biodegradable waterproof coating.

This is impregnated in the cardboard when it is created but still allows it to be recycled at the end of its use.

1. 0.89mm outer membrane: PVC-coated polyester fabric, transparent 2. 0.52mm five-layer inner membrane: flameproof polythene sheeting, non combustible paper, glass-fibre fabric, non combustible paper, flameproof polythene sheeting 3. 9/60/1950 mm horizontal plywood bracing in membrane sleeves

SUGAR CANE WATERPROOFING The development of a biodegradable waterproof coating made from the pulp of sugar cane could change the face of the paper coating industry. The process involves removing the cellulose from the sugar cane and putting it through a fermentation process that preserves the lignin, which is the waterproof part of cellulose. Conventional paper-making methods destroy the waterproof characteristic of lignin in treebased paper pulp. The new process would allow the recycling of treated cardboard, which is not possible with conventionally coated board.

Cristobel Correa also talks about Paper tubes being sensitive to water infiltration so waterproof layers need to be rolled into the tubes to provide protection from water infiltration.1 These layers can be added during manufacture such as aluminium foil or post manufacture such as building paper.

1 Correa, C Designing With Paper Tubes Structural Engineering International 4/2004 Temporary structures page 277

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For the temporary housing that he created following the earthquakes in Kobe and turkey the buildings were put up very quickly and cheaply. The vertical paper tubes as a result had a waterproof sponge which ran between the gaps to prevent water penetration.

The tubes were also treated using a biodegradeable waterproof coating.

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PHASE1,2,3,4,5,6

The waterproof strategy has changed with the structural development of the project. Initially the vertical tubes were going to be behind a poly carbonate screen for the first 2 phases.

When the design developed into using the structural A frames clad with horizontal cardboard tubes I was unsure about what I should use and whether I needed to have protection. Due to the aesthetical approach of the design I want the cardboard tubes to be very visible to the visitors. The horizontal tubes used for the cladding will also provide solar shading and view points out of the building so they can’t provide the waterproof envelope. They also can’t be clad in another material which is not transparent similar to the approach used in Westborough school.

POLY CARBONATE WATERPROOF COVERING

116

I have therefore decided that the tubes will all be impregnated with a biodegradable waterproof coating made from the pulp of sugar cane. This will allow the cardboard tubes to be waterproof but still be able to be recycled at the end of their usable life span. There will also be a detachable poly carbonate covering which will attach to the main structural frame. It will be transparent so the tubes can still be seen and detachable for separate recycling. It can also be removed if the research and development team are able to develop a new method for waterproofing.

The poly carbonate will also allow a facade to be created which will support water transfer from the roof to the ground for rain water harvesting. This will not provide a sufficient thermal barrier but the space will be hot from the effluent heat given off by the machine.

USED FOR GREY WATER IN TOILETS AND LANDSCAPE IRRIGATION

RAINWATER CYCLE

BREAK WATER TANK

MAIN WATER STORAGE TANK

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4 2 1

1:25 ROOF GUTTER DETAIL 1 rPET INTERNAL GUTTER 2 40MM POLYCARBONATE 3 273MM DIAMETER STEEL BEAM 4 GLAZING BAR DETAIL 5 100MM CARDBOARD TUBE TRUSS WITH rPET COMPONENT

3 5

1

2

8

3 4

TO

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6

5

9

1:25 GROUND SLAB DETAIL 1 300MM DIAMETER CARDBOARD TUBE 2 100MM PAPERCRETE SCREED 3 75MM NEWSPAPER INSULATION 4 300TH CONCRETE SLAB 5 20MM COMPRESSIBLE BOARD TO ALLOW MOVEMENT 6 DRAIN PIPE 7 40MM POLYCARBONATE COVERING 8 DRAINAGE CHANNEL 9 UNDERGROUND PIPES CONNECTED LEADING MAIN WATER STORAGE TANK

1

2 4

3

1:25 ROOF DETAIL 1 GLAZING BAR DETAIL WITH LEAD FLASHING 2 INTERNAL GUTTER 3 40MM POLYCARBONATE 4 DRAIN PIPE

These details show how the poly carbonate is attached to the cardboard tubes so that a gutter can run along the joint of the poly carbonate sheets. The gutter runs vertically and horizontally so that the rainwater can be transferred to the underground storage tank for the rainwater harvesting.

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120

FIRE RATING

To be used as a structural material cardboard needs to be able to remain structurally stable long enough for the occupants of the building to be able to make a safe exit. As cardboard is not a standardised material tests would need to be carried out to prove its structural capability in a fire. As I am unable to carry out my own tests safely I have looked at other results

carried out in a safe environment. Like all timber based products we know that paper burns, unless treated. But, in common with timber, card has the tendency to char rather than play an active part in a fire, with the charring protecting the surface. Also the more dense the cardboard the less easy to light it is.

121

ditions. Consequently, there were no specific tests FIRE RATING

Figure 3 where the s damaged

As part of the planning application for Westborough School (see pictures) fire tests had to be carried out to prove cardboards behaviour when subjected to fire.

This was carried out as part of the BBC Live lab broadcast. Some card panels were tested to see how they behaved with a flame thrower on them. One panel was thin card, untreated.

The second was a fire treated board. As the testing showed, the fire treated board gives a very good fire performance. In fact testing solid board is not fairly represented by this test. A recent test on untreated 5mm board narrowly failed the class 1 flame spread test.

carried o overcome aspect is

Jointing

Jointing i solution i not prac A series of tests were also carried out columns as part of th research and development for the preparati Local Zone in the Millennium Dome

by Shigeru Ban Architects. cardboard By applying intumescent varnish to cardboard using con tubes a Class 0 equivalent surface spread of flame can be achieved. Warrington Fire labs d carried out this test and have providedjointing such However in the Westborough building an over-cladding solution was used, which meant the underlying structure could easily be recycled because it is not contaminated with fire treatment.1

certification of such.

As part of a series of tests, ad-hoc tests were carried out on cardboard tubes to establish whether a fire classification could be achieved for the raw and treated material. A 10000C flame was held at the end of the tubes tested and in the same way that the surface of timber chars and protects the underlying material, cardboard behaves similarly. After 60 mins 150mm of a tube had been affected.

The application of the intumescent varnish to the external face did not provide different results. These tests did not result in obtaining some form of classification as it was not a requirement of the project. In addition, tests were carried out on honeycomb panels made -up of cardboard sheets sandwiching a honeycomb core, the surface of which was coated with intumescent varnish. The

Cost

1 Richard hennessy email Buro Happold

Figure 122 2 Ad-hoc ¢re test performed with a £ame-thrower for the BBC Tomorrow’s World Livelab television programme

Outline c below. Th to monito ing. This engineer contracto a real est project it estimates

m2

/mm2 aper

purpose of this test was to demonstrate that the air pockets inside the honeycomb did not promote the spread of fire through the panel as the varnish foamed up and protected the panel. A fire rating could have been achieved on the panels by providing a 1mm thick steel plate to the rear face.

No formal rating to fire resistance with similar behaviour to heavy timber framing. The paper tubes will not burn will char, but they will not support their own combustion. Also possible to apply intumescent coatings to the paper tube surface to further increase fire resistance.2

ds to l fire that uired protion. ision would perty

contests

2 Correa, C Designing With Paper Tubes Structural Engineering International 4/2004 Temporary structures page 277

123 Figure 3 Outcome of the ad-hoc ¢re test shown in Figure 2, where the surface of the panel has been blackened but not badly damaged

PHASE 3

124

As the proposed building is a new build industrial factory constructed out of cardboard, all Building Regulations need to be satisfied, so a completion certificate from the Local Authority can be awarded to prove the building work complies with the minimum standards of design and building work. As cardboard is not a standardised building material, its credentials as a suitable material will need to be proved with regards to its structural strength, fire resistance and resistance to contaminants and moisture. To comply with Part B Fire Safety the building will need to have protected fire escape stairs at 45m intervals along its length, as it is multistory, multi- occupancy building.23 The cardboard will be used as part of the external load bearing structure so it will need to be resistant to fire to provide means of escape from the building, for a minimum of 90 minutes if there are sprinklers or 120 minutes if there are not.24 If sprinklers were used then the effect of the added moisture on the cardboard would also need to be assessed on the length of time of its structural resistance. These time estimates are based on how the material behaves when tested under the British standard 476 Fire Test, which dictates the appropriate fire tests for the particular elements of structure/ materials.25 The materials performance is then rated nationally into Class 0 – 3, with Class 0 being the highest national product performance classification for lining materials.26 To gain Class 0 the cardboard would have to be defined as a non combustible material which is ‘Any material which when tested to BS 476-11:1982 does not flame nor cause any rise in temperature on either the centre (specimen) or furnace thermocouples.’ 27 Looking at test results28 carried out previously the cardboard receives a Class 0 rating with an aqueous based resin applied such as Paper Safe.29 As the material could pose a risk to the provision of the means of escape when assessing the application the Local Authority will have to consult with the fire authority before making its final decision under the fire precautions act 1971.30

45m

45m

30m

30m

24m

36m

42m

36m

42m

45m

36m

PHASE 6

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ENVIRONMENTAL STRATEGIES

The environmental strategies for the building project have been chosen due to their visibility in position. This is to highlight them to the visitors to the building so they understand the technologies. The aim is to use technologies which are powered using renewable sources. The heating and electricity comes from the biomass boiler which is powered by wood pellets which come from the Port of Tyne. This is due to the paper machine requiring a high amount of electricity a biomass boiler is essential.

Natural ventilation happens due to cross ventilation through the open windows and as a result of a stack effect created by the hot air movement. There is rainwater harvesting to ensure there is a constant

recycling of the water which is one of the raw materials needed for the paper process. The rainwater can be recycled for grey water in the building. There is also solar panels on the roof to make the most of the roof space. This electricity is surplus so can be directed back to the main grid to provide the surrounding area with electricity. The building is also divided up into two different zones one which has a thermal envelope and the other which doesn’t. This is to ensure an effective use of the heating that is generated and maximise the visitors experience of the cardboard structure as they are able to get up close to it.

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WOOD PELLET STORAGE FOR 1 MONTHS SUPPLY

PORT OF TYNE

PAPER MACHINE/LIGHTING/ GENERAL USE

STEAM TURBINE

NATIONAL GRID

STEAM

BOILER

UNDER FLOOR HEATING PAPER DRYING CYLINDERS

GREY WATER TREATED

STEAM CONDENSES

HEAT EXTRACTED

CHP WOOD PELLET BOILER - FUEL CONSUMPTION REDUCTION AND COMES FROM A RENEWABLE ENERGY SOURCE

A WOOD PELLET CHP UNIT WILL BE LOCATED ON SITE TO GENERATE THE ELECTRICITY AND HEATING NEEDED FOR THE BUILDING AND THE PAPER MACHINE. THE CHP UNIT WOULD PRODUCE HIGH GRADE HEAT IN THE FORM OF STEAM THAT WOULD BE USED IN THE PAPER DRYING CYLINDERS, LOW GRADE HEAT TO BE USED IN OTHER PROCESSES AND TO HEAT THE BUILDING AND GENERATE ELECTRICITY TO POWER MACHINERY AND THE BUILDING.

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4

1:25 ROOF GUTTER DETAIL 1 rPET INTERNAL GUTTER 2 40MM POLYCARBONATE 3 273MM DIAMETER STEEL BEAM 4 GLAZING BAR DETAIL 5 100MM CARDBOARD TUBE TRUSS WITH rPET COMPONENT

2 1

3 5

1

2 4

USED FOR GREY WATER IN TOILETS AND LANDSCAPE IRRIGATION

3

1:25 ROOF DETAIL 1 GLAZING BAR DETAIL WITH LEAD FLASHING 2 INTERNAL GUTTER 3 40MM POLYCARBONATE 4 DRAIN PIPE

RAINWATER CYCLE

BREAK WATER TANK 1

6

2

MAIN WATER STORAGE TANK

8

3 4

5

9

1:25 GROUND SLAB DETAIL 1 300MM DIAMETER CARDBOARD TUBE 2 100MM PAPERCRETE SCREED 3 75MM NEWSPAPER INSULATION 4 300TH CONCRETE SLAB 5 20MM COMPRESSIBLE BOARD TO ALLOW MOVEMENT 6 DRAIN PIPE 7 40MM POLYCARBONATE COVERING 8 DRAINAGE CHANNEL 9 UNDERGROUND PIPES CONNECTED LEADING TO MAIN WATER STORAGE TANK

RAINWATER HARVESTING - UTILIZING RAIN WATER REDUCING DEMAND ON STERILISED MAINS WATER SUPPLY THE LARGE ROOFSCAPE IS UTILIZED TO COLLECT RAINWATER THROUGH THE PITCHING OF THE POLYCARBONATE SHEETS AND A SERIES OF GUTTERS. THE WATER IS COLLECTED VIA AN UNDERGROUND DRAIN AND STORED FOR USE AS GREY WATER IN THE BUILDING AND IRRIGATION FOR THE LANDSCAPE

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1:20 SECTION A - A ROOF GLAZING DETAIL 1 GLAZING BAR DETAIL 2 40MM POLYCARBONATE 3 273MM DIAMETER STEEL BEAM 4 100MM CARDBOARD TUBE TRUSS WITH rPET COMPONENT 5 GLAZING BAR DETAIL FOR ROOF LIGHT

1 2

5

3 4

AIR OUT

AIR OUT A A

AIR IN

AIR IN

CROSS NATURAL VENTILATION - REMOVING THE NEED FOR MECHANICAL VENTILATION STACK EFFECT CREATED DUE TO THE HEATING OF INTERNAL AIR THROUGH GLAZED OUTLETS AT TOP OF TRIANGULAR PODS - THIS DRAWS AIR FROM THE OPPOSITE TRIANGULAR POD THROUGH THE PERMEABLE FLOOR GRATING COOLING THE SPACE

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SPACE HEATING - THERMAL ENVELOPE

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EXTERNAL ENVELOPE DETAIL TRIANGULAR POD

1 40MM POLYCARBONATE 2 100MM CARDBOARD TUBES 3 300MM CARDBOARD TUBES

EXTERNAL ENVELOPE 1:50

1

2 3

EXTERNAL AND INTERNAL ENVELOPE - UTILISING NATURAL DAYLIGHT AND ZONED SPACE HEATING REDUCING ELECTRICITY CONSUMPTION

EXTERNAL FACADE IS PROVIDES A WATERPROOF SKIN THROUGH THE USE OF POLYCARBONATE FOR THE MACHINE HALLS. DAYLIGHT IS UTILISED THROUGH THE SPACING OF THE HORIZONTAL TUBES WHICH ALSO PROVIDE SOLAR SHADING. AN EXTRA SKIN IS PROVIDED IN THE THREE VERTICAL ZONES WHERE THE FUNCTION OF THE SPACES REQUIRE SPACE HEATING THROUGH THE USE OF UNDER FLOOR PIPES POWERED BY THE CHP BOILER.

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INTERNAL ENVELOPE DETAIL

1 2

SECTION A -A 1:5

3

4

5

1 GLAZING BAR 2 GASKET 3 40MM POLYCARBONATE SHEET 4 BOTTOM SECTION OF GLAZING BAR WITH 8MM COACH BOLT 5 100MM CARDBOARD TUBE

10 A

A 2 3

11

12 13

4

1 40MM DOUBLE SKIN POLYCARBONATE 2 STEEL ANGLE 3 100MM X 100MM STEEL ANGLE TO SUPPORT CORRUGATED STEEL PANELS 4 273MM DIAMETER STEEL 5 STEEL U CHANNEL 6 100MM PAPERCRETE SCREED 7 75MM NEWSPAPER INSULATION 8 300MM CONCRETE SLAB 9 DPM 10 100MM CARDBOARD TUBE 11 rPET 100MM DIAMETER CRUCIFORM COMPONENT 12 100MM PAPERCRETE SCREED WITH UNDER FLOOR HEATING BARS 13 CORRUGATED STEEL PANELS 14 273 MM LIGHTWEIGHT STEEL BEAMS 5 6 7 8

INTERNAL ENVELOPE 1:25

9

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POLY CARBONATE DATA SHEET

Poly carbonate has a u value = 1.2 w/m2k This value will allow the poly carbonate to provide insulation for the public spaces

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Visual appearance Card has its own visual appearance, and this is often desired as part of the concept to make it apparent that it is card that is being used.

Naturally is can also be added to with any paint or paper system to give an appearance like any other internal surface. One benefit of the panel system is the opportunity it brings to produce panels of a particular design by screen printing. This was used for the external cladding, as shown in the figures of the external skin in the over-cladding section.1 CARDBOARD PROPERTIES Has a stiffness of about 1/5 of softwood Is sensitive to load duration sensitive to variations in moisture content up to about 7%. After this value, strength reduces about 10% for every 1% increase in moisture content has a significant rate of creep, with creep occurring with as little as 10% failure load allowable bending stress is generally 50% greater than allowable compression strength

youngs modulus(N/mm3) allowable compressive strength (N/mm2) allowable bending stress (N/mm2)

short term 1000- 1500 4.4 6.6

long term 1000 2.2 3.3

The failure strength of card is of little significance as it tends to creep or deform under load.

It is only possible to use a small proportion of its total strength in the long term. A factor of 10 was used to ensure that creep was not a problem.

Like timber, paper tubes are susceptible to visco elastic behaviour or creep, that is, an increasing deflection over time during the application of a fixed load. The tests carried out on tubes have found that creeep is negligible when loads are limited to 10% of the compressive strength. This value was used in the design of the load bearing elements. 2 CARDBOARD AS A CONSTRUCTION MATERIAL Limit compressive, tensile and bending stresses to 0.8N/MM2 (FROM 8.1 TIMES) Limit bending stresses at fixings to 1.4 n/mm2 limit glue shear stress to 0.3 N/MM2 Adopt a youngs modulas value between 1000 and 1500 n/mm2 Limit mositure content variation by use of water resistant paper and poly-ethlene or aluminium foil 3 As a result, cardboard allows the designer to pursue structures that are not based on precedent and go beyond conventional building structures.

Cardboard and paper products are available in a variety of standard forms, mainly manufactured for the packaging industry. The following cardboard products are available.

Tubes - manufactured by rolling multiple layers of spirally wound paper plies over a spindle. The layers are glued together by starch or PVA. The tube wall thickness depends on the number of plies but can range up to 16mm.

Tube diameters up to 600mm are commonly available.

Panels - manufactured by laminating sheets of paper or particles for solid boards.

1 2 3

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Richard Hennesey email Buro Happold

Correa, C Designing With Paper Tubes Structural Engineering International 4/2004 Temporary structures page 277 Cripps, A Cardboard as a construction material Building research and information (May - June 2004) 32 (3) 207-219 spon press taylor and francis group page 209

Honeycomb boards can be made by pressing paper pulp into a honeycomb mould and then sandwiching the honeycomb structure between sheets of paper: by gluing multiple sheets of paper together and pulling them apart or by gluing two halves of moulded honeycomb panels together.A number of Land T-shaped and RHS sections are also available in cardboard.

Like other structural materials cardboard is best used in forms that exploit its inherent strength and material behaviour. Due to the manufacturing process cardboard is an anisotropic material, hence the material strength varies greatly depending on the direction of the stresses. It is most efficiently used to transfer axial and in-plane stresses only, a point which should be kept in mind when deciding the structural form and load path.

Columns - axially loaded columns can be designed from cardboard tubes.Load-bearing columns are generally of a large diameter and the ratio between the tube wall thickness and diameter is high.Hence tubes tend to fail locally in buckling.Overall buckling of the tubes is less likely due to the low slenderness ratio of the sections.

Beams - can be designed using sheets of honeycomb cardboard or sections. The support conditions of beams need to be considered carefully to avoid stress concentration and minimise shear deflection and shear creep.The use of tubes as beam elements is not recommended; their bending capacity is low as the outer surface layer is not continuous.

Walls - flat panels can be used for the design of walls, either load-bearing, self-supporting or mounted to a primary frame. In all cases the stiffness of the wall and its performance under lateral loads are critical.Stiffness can be enhanced by stiffeners, cross walls or by designing the wall as a folded plate. If the panels are mounted on a primary frame, the cardboard acts as a cladding material.

Buro Happold has established a number of tentative design parameters for cardboard.

They are based on project-specific tests and particular products.As there are no general structural requirements and standards for cardboard products, the parameters need to be reassessed prior to each new project. lMaterial properties of cardboard: Cardboard tubes Tensile/compressive strength 8.1 N/mm Design tensile/compressive strength taking account of creep effects and a factor of safety (FOS) of 10: 0.8 N/mm 2E-value: 1,000-1,500 N/ mm 220mm-thick honeycomb sheets Bending strength: 6.9 N/mm 2Design tensile/ compressive strength taking account of creep effects and a FOS of 10: 0.6 N/mm 2E-value: 1,000 N/mm 2All values relate to a stress direction parallel to the surface.Stresses perpendicular to the surface have not been tested. 4

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