Constructing Environments Week #04 Definitions of key terms learnt this week Joist – A length of timber or steel supporting part of the structure of a building, typically arranged in parallel series to support a floor or ceiling Steel decking – A type of cold-formed corrugated metal most commonly used to support the insulating membrane of a deck or roof Span – The full extent of something from end to end; the amount of space that something covers Girder – A large iron or steel beam or compound structure used for building bridges and the framework of large buildings Concrete Plank – A hollow-core or solid, flat beam used for floor or roof decking Spacing – To position (two or more) items at distance from one another Span and spacing
Floor systems Concrete slab has been allowed to set that causes it to be strong enough to
*Concrete (from right to left) Slab that spans in two directions, and one that spans the shorter distance between supporting structures *Timber (from right to left) The joists are further apart, hence floorboards are slightly thicker compared to the ones on the left *Steel (from left to right) There are open webbed trusses that are light weight joist, closely spaced compared to the one on the right hence flooring itself on right is needed to be stronger
Concrete Systems Slabs of various types are used to span between structural supports. These can be one way or two way spans *concrete thickness is generally rounded off to be the span of the slab divided by 30
Steel systems Steel framing systems take various forms, with some utilizing heavy gauge Structural steel members and others using light gauge steel framing. In many instances a combination of member types and materials are combined (eg heavy and light members) depending on their structural function.
*Opened web joists spanning from top chord to bottom chord, efficient usage of steel. There’s also the advantage that services such as water pipes can be carried through the open web of a joist. Steel framing systems sometimes combine with concrete slab systems to where the particular benefits of steel framing and shallow depth floor slab systems are desired. The spanning capabilities of the particular materials help to determine the spacing requirements of the supports.
Here there is a folded decking and the concrete is layered on top of that decking and the decking helps to provide the tensile strength necessary for concrete span
Timber systems Traditional Timber Floor Framing systems use a combination of bearers (primary beams) and Joists (secondary beams) The span of the bearers determines the spacing of the piers or stumps and the spacing of the bearers equals the span of joists *floor systems typically do have a lot of joist and typically to keep their cross section small, there is a tendency not to span it from wall to wall but rather using bearers in between to reduce size of material Beams and cantilevers
Concrete Components When cement is mixed with water it binds the sand and gravel aggregates together to make the hard solid material we call concrete
Concrete – provenance When the cement powder and water are mixed, a chemical reaction takes place and heat is released. Process is called hydration. During this process crystals are formed that interlock and bind the sand, crushed rock and cement/water paste together. If too much water is added to the concrete mix, the final concrete will be weak. If too little water is added, the concrete mix will be too stiff and very difficult to work with. Concrete – Process Advantages of concrete: fluid and shapeless before it hardens, hence can be formed into any shape desired Formwork is the term used for temporary support or moulds used to hold the liquid concrete in place until it becomes hard Formwork can be built at site (in-situ) or in factory (pre cast) out of a range of different materials – timber, metal, plastic, formply, etc.
*lining can be plywood and is held in place temporarily by timber studs and whalers and is temporarily braced in position *The concrete is poured in between the two layers of formwork then it is taken away after the concrete is set
During the curing process the formwork needs to be supported as the weight of the wet concrete is very heavy. This is done by using props and bracings of various types. Concrete generally reaches 75% of compressive strength in approximately 7 days with testing for the required strength occurring at 28 days. Once the concrete is hardened and strong enough, the formwork is carefully removed. Formwork is often removed, stored and reused or it may stay in place forever (sacrificial formwork) Concrete – reinforcement Concrete is also known as ‘artificial stone’. This suggests that the properties of concrete and stone are similar. Concrete is very strong in compression but is weak in tension. To improve its structural performance, steel (very strong in tension) reinforcement in the form of mesh or bars is added. The resulting material is known as reinforced concrete. Concrete – properties (The properties inn the ‘fresh wet’ – plastic state- and hardened state depend on the physical
characteristics, chemical composition and the proportions of the components. In the list below it is the hard state that is addressed)
Hardness – High. Can be scratched with metal object Fragility –Low. Can be chipped with hammer Ductility – Very Low Ductility
Flexibility/Plasticity – Low flexibility and plasticity Porosity/permeability – Medium. Low. Depending on proportions and components (aerated or high water ratio concrete has a high porosity vs waterproof concrete that is created when permeating reducing admixtures are included in the concrete mix) Density – Medium – high. Around 2.5x more dense than water Conductivity – Poor conductor of heat and electricity Durability/life span – Typically very durable Reusability/recyclability – Medium – Low. Can be reused when crushed to be used as aggregate for new concrete elements Sustainability & carbon footprint – High embodied energy. Non-renewable. Long Lasting Cost – Generally cost effective. Labor dependant for formwork/pouring
Concrete Considerations Concrete is permeable (not completely waterproof). This is one of the main sources of problem in concrete. If the steel bars are too close to the surface they will not be protected from moisture and oxidation. Leading to both aesthetic and structural degradation of the concrete. Another common cause of problems is poor vibration of the concrete during the pouring process. Concrete is vibrated to get rid of air bubbles that get caught during pouring process. These bubbles can compromise the structural performance of the element and in worse case scenario result in the element failing.
Pre-cast Concrete In any concrete element that has been fabricated in a controlled environment and then transported to site for installation. This process ensures a much more standardized outcome that avoids the quality control issues associated with in-situ concrete. Pre-cast elements also allow work on site to progress at a much faster rate.
Pre-cast concrete uses It is widely used in many applications, often associated with the structure of a building, bridge or civil works, forming part of the primary structure or selfsupporting panel type elements. It is rarely used in footings, it is more common in retaining walls, walls and columns.
Pre-cast concrete – Joints 1. Construction Joints – The panel/elemental nature of pre-cast concrete mean that joints naturally occur when precast element meets another 2. Structural Joints – The type and performance of the structural connections joining the precast elements to each other and to other parts of the structure are critical for the overall performance of the building *Construction and structural joints will generally depend n the desired aesthetic outcome Pre-cast concrete considerations Pre-cast concrete elements can be limited in size due to transport On site changes are very difficult to incorporate
Constructing Environments Week #05 Definitions of key terms learnt this week Stud- i)An upright timber in the wall of a building to which laths and plasterboards are nailed ii) A large-headed piece of metal that pierces and projects from a surface, especially for decoration Nogging – brickwork in a timber frame (horizontal piece of wood fixed to a framework to strengthen it) Lintel – A horizontal support of timber, stone, concrete, or steel across the top of a door or window Buckle – Bend or give way under pressure or strain Axial Load – A structural frame system that is a combination of primarily vertical and horizontal members that are designed to transmit applied Seasoned Timber – Timber dried to a moisture content that is stable
Short Column and Long Column Short Columns are shorter (length) and thicker (cross-section) Long Columns are taller (length) and slimmer (cross-section) Columns are considered short if the ratio of effective column length to the smallest cross section dimension is less than 12:1. Short Columns are structurally adequate if the load applied to the column cross section does not exceed the compressive strength of the material. Compressive Strength (Pa) = Load (N) / area (mm^2) Long columns becomes unstable and fail by buckling *Short Columns become shorter when a compressive load is applied and then fail by Crushing (shear) when the compressive strength is exceeded *The actual length of Long Columns and how they are fixed at the top and bottom of the columns determines how they will buckle and how much load the column can carry Wall Systems
Structural Frames -Concrete frames Typically use a grid of columns with concrete beams connecting the columns together -Steel Frames Typically use a grid of steel columns connected to steel girders and beams -Timber Frames (Post and beam) Typically uses a grid of timber Posts or Poles connected to timber beams *Bracing of members between bays or at the corners of post/beam junction is required to stabilize the structure
Load Bearing Walls -Concrete Load bearing walls can be achieved using either in situ or precast elements *The low bearing panels may also provide support for Spandrel Panels over and link into other structural elements -Masonry Reinforced Masonry load bearing walls can be constructed from core filled hollow concrete blocks or grout filled cavity masonry *Bond beams over openings can be created using special concrete blocks which are filled with concrete to bond the individual units together. After the concrete has cured, the temporary propping can be removed, leaving only the appearance of the concrete block wall. Bond beams are used as an alternative to steel or concrete lintels. Solid Masonry load bearing walls can be created with single or multiple skins of concrete masonry units or clay bricks *The skins of masonry are joined together using a brick (with header showing in face of wall) or with metal wall ties placed within the mortar bed Cavity Masonry are typically formed from two skins of masonry *Advantages of this construction solution include: Better Thermal performance and opportunities for insulation within the cavity, better waterproofing, and the opportunity to run services within the wall cavity *Presences of a DAMP PROOF COURSE and WEEP HOLES in a wall are indicators that the wall is a cavity wall rather than a solid wall
Stud Walls -Stud Framing -Light gauge steel framing -Timber framing Metal and timber stud framed walls use smaller sections of framing timber or light gauge framing steel to meet the structural demands of the construction *Smaller sections means that the structural members are repeated at smaller intervals and require restraining along their lengths with rows of noggings to prevent the long thing members from buckling *Stud framing generally consists of top plates, bottom plates, vertical studs, noggings, cross bracing and ply bracing *Combinations of 1 skin of non-structural masonry and 1 skin of structure frame wall are widely used in the construction industry as the brick work is ties to the stud work Timber to Wood
Early Wood -Rapid growth at beginning of growth season -Thin, large cells – lighter colour
Late Wood -Slower growth, often limited by lack of water -Thick small cells – darker colour -Gives the growth ring
Growth -Generally 1 ring per year
Direction, Strength and Stiffness Grain Direction – Determines the structural performance of wood It is strong parallel to grain and stuff parallel to grain Weak when perpendicular to grain Why is timber seasoned? -To adjust the moisture content so it is appropriate -To provide increased dimensional stability What moisture is removed? -Free moisture (voids in cells) -Bound moisture (cell walls)
How is it removed? -3 ways Air seasoning – Cheap but slow – 6 months to 2 years per 50mm thickness Kiln Seasoning – Typically 20-40 hours to dry to ~12 % Solar kiln seasoning –Less expensive to run Engineered Timber Products
Constructing Environments Week #06 Definition of key terms learnt this week Rafter – A beam forming part of the internal framework of a roof Purlin- A horizontal beam along the length of a roof, resting on principals and supporting the common rafters or boards Cantilever – A long projecting beam or girder fixed at only one end, used in bridge construction Eave- The part of a roof that meets or overhangs the walls of a building Portal Frame – A rigid structural frame consisting essentially of two uprights connected at the top by a third member Soffit – The underside of an architectural structure such as an arch, a balcony, or overhanging eaves Alloys – A metal made by combining two or more metallic elements, especially to give greater strength or resistance to corrosion Top Chord – The top beams in a truss Truss – A strong structure comprising of one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes. Truss A framework, typically consisting of rafters, posts, and struts, supporting a rood, bridge or other structure. It is generally used to make structures more stable.
Roofing Strategies and systems
Concrete Roofs ďƒ Generally flat plates reinforced concrete (or precast slabs with a topping of concrete) *The top surface is sloped inward towards drainage points and the entire roof surface finish with applied waterproof membrane Structural Steel Framed Roofs Flat structural steel roofs consists of a combination or primary and secondary roof beams for heavier roof finishes such as metal deck/concrete; or roof beams and purlins for lighter sheet metal roofing Sloping structural steel roofs consist of roof beams and purlins and lighter sheet metal roofing Portal frames consist of a series of braced rigid frames (two columns and a beam) with purlins for the rood and girts for the walls, walls usually finished with sheet metal Trussed Roofs are framed roofs constructed from a series of open web type steel or timber elements *Trusses are manufactured from steel or timber components, fixed together to form efficient elements able to span long distances Space frames are 3D plate type structures that are long spanning in two directions. *Linear steel sections of various cross section types are wielded, bolted or threaded together to form matrix-like structures
Light framed roofs Gable roofs are characterized by a vertical, triangular section of wall at one or both ends of the woof
(Materials: timber, cold-formed steel sections (sometimes heavier steel (UB or PFC) for major beams)) Hip roofs are characterized by a vertical, triangular section of wall at one or both ends of the roof (Materials: timber, cold-formed steel sections) Introduction to metals Metals are malleable, ductile and not brittle
Properties of metal Hardness – Varied, depending on type Fragility – Low generally will not shatter Ductility – High Flexibility/plasticity – Medium – High flexibility and high plasticity while heated Porosity/Permeability – Generally impermeable – used for gutting, flashing Density – High (from 3x density of water for aluminium to 19x density of water for gold Conductivity – Good conductors of heat and electricity Durability – Can be very durable/ varies depending on type, treatment, finishing (protection) and fixing Reusability/recyclability – high Sustainability and carbon footprint – very high embodied energy, recycable and renewable if correctly managed Cost- generally cost effective Considerations for metal Water related damage – oxidation and corrosion causes rust Protect against water to reduce corrosion Avoid prolonged exposure to moisture Seal against moisture Chemical treatment Plates and grids
Plates – A thin, flat sheet or strip of metal or other material, typically one used to join or strengthen things or forming part of a machine Grids – A framework of spaced bars that are parellel to cross each other Ferrous metals and alloys Wrought iron is widely used in bars for windows and doors and for decorative elements. Still used today but is expensive as it is labour intensive Cast iron very rarely used in contemporary construction due to its weight and brittleness, generally only used for compression elements Steel Is very strong and resistant to fracture, it can also be formed into many different shapes. Long lasting and resistant towear too
Steel types and uses 1. Framing – Columns, beams, purlins, stud frames, etc. Depending on shape of structural element, it consists of two main types Hot rolled steel Elements are shaped while metal is ho. More material is required for this process. Used as primary structure elements. Often protected from rusting and corroding by coatings. Joints are wielded and bolted Cold formed steel Elements are folded from sheets that have been previously produced and cooled down. Used as secondary structure. Often protected by hot dip process. Joints are bolted or screwed. -Reinforcing bars – due to its good tensile resistance steel is used in conjunction with concrete to produce reinforced concrete 2. Steel sheeting – Cladding and roofing (must be protected from weather exposure) 3. Stainless steel alloys *Chromium is the main alloying element *Rarely used as primary structure due to cost (only harsh environments or particular areas such as kitches) Aluminium properties Very light Non-magnetic and non sparking Easily formed, machined and cast *extruded sections are common for window frames, door handles and catches for windows Rolled aluminium is used for cladding panels, heating and air conditioning systems
Copper properties Very malleable and ductile Good conductor of heat and electricity Turns green when exposed to weather for too long *used as roofing material, also widely used for hot and cold domestic water and heating pipework and electrical cabling Zinc properties Often placed as thin layers onto other steels to protect said iron from corrosion Used as cladding material for both roofs and walls Reasonable conductor of electric Lead properties Used to be used for roofs, cornices, tank linings, flashing strips , however less used now because it is known to be toxic to humans
Activity Presentation Due to copyright infringements, photos for the week’s activity is not allowed on the logbook. Hence it can only be explained by text.
Constructing Environments week #07 Definition of key terms learnt this week Vapour barrier – A sheet or membrane that is steam-tight. It prevents steam from crossing or stagnating in the walls. It can refer to any material for damp roofing, typically a plastic or foil sheet that resists diffusion of moisture through wall, ceiling and floor assemblies of buildings and of packaging. Gutter – A shallow trough fixed beneath the edge of a roof for carrying off rainwater Parapet – A low protective wall along the edge of a roof, bridge or balcony Down pipe – A pipe to carry rainwater from a roof to a drain or to ground level Flashing – A strip of metal used to stop water penetrating the junction of a roof with another surface Insulation – The action of insulating something Insulate – Protect (something) by interposing material that prevents the los of heat or the intrusion of sound Sealant – Material used for sealing something so as to make it airtight or water tight Heat and moisture
For water to penetrate a building all three conditions must occur: i) an opening ii) water present at the opening iii) A force to move water through the opening
Three different strategies can be employed to prevent water penetrating i) remove openings ii) keep water away from opening iii) neutralize the forces that move water through openings Openings can be: Planned elements (windows, doors, skylights) or Unplanned elements
Unplanned elements can be created by -Poor construction workmanship -Deterioration of materials (over a period of time or through incorrect application of materials)
Removing openings can be done by sealing openings with -sealants (silicone) -Gaskets (performed shapes made from artificial rubber) *Both of them rely heavily on correct installation and will detoriate over time due to weathering
Keeping water from openings can be done by redirecting water from openings -Grading (sloping) roods so that water is collected in gutters which then discharge water to downpipes and stormwater systems -Sloping window and door sills and roof/wall flashings -Sloping the ground surface away from the walls at the base of the building Neutralizing the forces Forces to be considered are as follows -Air pressure differential -Momentum -Surface tension and capillary action -Gravity
ďƒ Strategies to neutralize the forces -Use slopes and overlaps -Surface tension and capillary action strategies *Typically using a drip or break between surfaces to prevent water clinging to the underside of surfaces (such as windowsill/parapet capping) -To inhibit momentum, gaps are often constructed in more complex labyrinth shapes’ -To make for the air pressure due to hole sizes, an air barrier is introduced to the internal side of the labyrinth, a ventilated and drained PRESSURE EQUALISATION CHAMBER (PEC) is created and the water is no longer pumped to the inside of the assembly.
Controlling heat Heat gain and heat loss occur when -heat is CONDUCTED through building envelope -building envelope and building elements are subjected to RADIANT HEAT sources -THERMAL MASS is used to regulate flow of heat through building envelope
Ways to control heat Conduction -Thermal insulation to reduce heat conduction -Thermal breaks made from low conductive materials like rubbers and plastics to reduce the heat transfer from outside to inside (vice versa) when using highly conductive materials -Double glazing or triple glazing so that the air spaces between glass panels reduces the flow of heat through the glazed elements Radiation -Reflective surfaces such as low-e glass, reflective material stops building elements from becoming warm/hot -Shading system like verandahs, eaves, solar shelves, blinds, screens and vegetation to prevent radiation striking the building envelope Thermal mass Large areas of exposed thermal mass can be used to absorb and store heat, the heat is released when the temperature drops and this system works well when theres a huge difference in temperature between day and night *materials traditionally used are masonry, concrete, water bodies Controlling air leakage If building has opening, air present at opening, force to move air through opening, air will move through building and spaces will become draft in cold weather and leak out heating. Strategies that can be done are as follows: i) eliminating any one of the causes ii) wrapping building in polyethylene or reflective foil sarking as an air barrier iii) weather stripping around doors and windows and other openings Rubber Hardness – Harder rubbers resist abrasion, softer rubbers provide better seals Fragility – Low generally will not shatter or break Ductility – High (heated), varied (cold) Flexibility/plasticity – High flexibility, plasticity and elasticity Porosity/permeability – All rubbers are waterproof Density – Approx 1.5 density of water Conductivity – Very poor conductors of heat/electricity Durability – Can be very durable Reusability/recyclability – High
Sustainability & carbon footprint – Embodied energy varies greatly between natural rubber (very low) and synthetic rubbers (medium), renewable if correctly managed Cost – Generally cost effective Used in -seals (SILICONE) -gaskets (EDPM) and control points (NEOPRENE) -flooring -insulation -hosing and piping
Considerations -Weather related damage (especially sunlight) Plastics
Types and uses 1. Thermoplastics are mouldable when heated and become solid again when cooled (eg. Polythene, Perspex, acrylic, pvc, vinyl, polycarbonate) 2. Thermosetting plastics Can only be shaped (moulded) once (eg. Polystyrene (insulation panels), laminex (finishing surfaces) 3. Elastomers (synthetic rubbers) (eg. EDPM, Neoprene, Silicone)
Properties
Hardness – Medium-low depending on type Fragility – Low-medium. Generally will not shatter or break, sunlight and high temperatures can degrade some plastics quickly Ductility – High (heated), Varied (cold) Flexibility – High flexibility and plasticity Porosity/permeability - Waterproof Density – Low (0.65 density of water for polypropylene to 1.5x for pvc) Conductivity – Very poor conductors of heat and electricity Durability/lifespan – Can be durable, depending on type, finishing and fixing Reusability/recyclability- High for thermoplastics and elastomers, not thermosetting Sustainability & carbon footprint – embodied energy varies greatly between (recycled/not recycled) plastics are petrochemical derives so not renewable Cost – cost effective Considerations
-Weather related damage (especially sunlight) Paints are liquids until applied on a surface *Clear paints are called lacquers or varnishes Components
BINDER – The film-forming component of the paint DILUENT – Dissolves the paint and adjusts its viscosity PIGMENT – Gives the paint its colour and opacity. (natural or synthetic) Types and uses 1. Oil based i) used prior to plastic paints ii) very good high glass finishes iii) not water soluble (brushes cleaned with turpentine) 2. Water based i) most common today ii) durable and flexible iii) tools and brushes cleaned with water
Properties Colour consistency – Colour of paint resistant to fading , especially when in uv light (sunlight) Durability – Paint need to resist chipping, cracking and peeling, exterior painted surfaces have to resist the effect of rain, air pollution and the uv light. (powder coating and PVF2 are harder and more durable) Gloss – Surface finishes can range from matt through to gloss Flexibility/plasticity – Water based latex paint is more flexible than oil based paint No activity
Constructing Environments week #08 Definitions of key terms learnt this week Window sash – A framework that holds the panes of a window in the window frame Deflect – Cause something to change direction Moment of inertia – A quantity expressing a body’s tendency to resist angular acceleration, which is the sum of the products of the mass of each particle in the body with the square of its distance from the axis of rotation. Door furniture – The handles, locks and other fixtures on a door Stress – Pressure or tension exerted on a material object Shear force – Component of stress coplanar with a material cross section. In other words, unaligned forces pushing one part of a body in one direction, and another part of the body in an opposite direction.
Strategies for openingDoors and windows
^modern doors
^traditional doors Different types of doors : Aluminum doors and frames Steel doors and frames
Gypsum box
Different types of windows: Curtain windows – Also a walling system, ensure loads are carried around the columns instead of the windows Steel Windows – Not common in Aus due to price, frames are wielded together Aluminum windows – used domestically, used in commercial buildings, lots of people required to lift and align
Glass Most glass created from silicon/sand, its an extremely inert material -Materials used to make glass are called a former (eg silica) -Fluxes (eg. Soda ash/potash) helps formers to melt at lower and more practical temperatures -Stabilizers (eg. Limestone) combine with formers and fluxes to keep the finished glass from dissolving or crumbling Properties Porosity/permeability – Non-porous/waterproof Density – Medium – High, 2.7x denser than water Conductivity – Transmit heat and light but not electricity Hardness – High, can be scratched with a metallic object Fragility – High, differs depending on the type of glass (tempered glass not as brittle as float glass) Ductility –Very Low Flexibility/plasticity – Very high flexibility and plasticity when molten / low to very low when cooled Durability/ lifespan – Typically very durable – chemical, rust and rot resistant Reusability/recyclability – Very High
Sustainability & carbon footprint – Typically high embodied energy and carbon footprint but ease of recycling/reuse makes It a popular sustainable product Cost –Generally expensive to produce and transport
Glass types Flat – (typically sheets of clear or tinted float, laminated, tempered, wired, etc) Shaped - (curved, blocks, channels, tubes, fibres) Float glass is the most common glass production process in the world. 1. Clear Float Glass Simplest and cheapest glass product available in market. No further treatment beyond float fabrication 2. Laminated glass A tough plastic interlayer (PVB) is bonded together between two glass panes (as in a sandwich) *This improves the security and safety of glass as even though glass can still crack, the sharp fragments tend to adhere to the plastic rather than falling apart. 3. Tempered glass Produced by heating annealed glass to around 650 degrees celcius, at which point it begins to soften. The surfaces of this glass are then cooled rapidly creating a state of high compression in the outer surfaces of the glass *As a result the bending strength is increased by a factor of 4-5 times that of annealed glass and makes it break into smaller, pellet shaped pieces rather than sharp shards, improving safety of the product
Other types & prodcuts of glass Tinted glass – Useful in sun-exposed situations to reduce visible light transfer Wired glass – Similar concept to a laminated glass – a steel wire mesh is used instead of a plastic firm – traditionally accepted as a low-cost fire glass Patterned glass – Made with a rolled glass process – typically used when privacy and light are required Curved glass – This type of glass is produced in moulds that are created to meet the specific design requirements - expensive Photovoltaic glass – with integrated solar cells Glass Channels – Used in façade systems Slumped and formed glass – used as design features Glass Fibres – hair like strands – used in telecommunications
Double and triple glazing
Activity Drawing up a 1:1 scale of a section of the building chosen from the Pavilion set This was the section that I have chosen to draw out for this week’s activity. I have labeled and also measured how the drawing will be in length when the 1:1 drawing will be drawn out
Going onto site to look at the actual building itself, this was the building that was required to be drawn.
Details of the building annotated
This was the result of the 1:1 drawing. The walls for these buildings didn’t depend on the double glazed glass, it however depended on the columns that were mixed with a certain spacing along the glass panels. The top section of the wall has a steel section because there was the need to insert a door, and there was no reason to recreate a door to be as tall as the building. The inside of the building is laid out with carpet whereas the outside was concrete. There is also a vapour barrier installed underneath the steel part of the floor. The double glazed windows are required these days for a building to reach a green star rating of 5 and it also helps to keep the building at its moderate temperature than the outside.
Constructing Environments week #09 Definitions of key terms learnt this week Sandwich panels – a type of panel that consists of two thin aluminum sheets bonded to a non-aluminum core, it is often used for external cladding or facades of buildings, insulation and signage. Skirting – a wooden board running along the base of an interior wall Bending –movement that causes the formation of a curve Composite beam – i)A steal beam that has concrete decking above it, and which is connected to the concrete by shear connectors, which cause the steel and concrete to act together.
ii) A structural member composed of two or more dissimilar materials joined together to act as a unit. Construction Detailing
*To provide an effective seal against the passage of water and air, a joint sealant must be durable, resilient, and have both cohesive and adhesive strength. Sealants can be classified according to the amount of extension and compression they can withstand before failure. Construction Detailing : Health and Safety
Depending on building occupants, floor area and height and floor area, different standards of fire insulation and fire resistant materials are needed. Ramps into and out of buildings for the disabled, etc.
Materials are limited to those that are not of high risk of spreading fire Construction Detailing : Ageing Gracefully
Some buildings detoriate quick with water, materials appropriately picked will last longer in the harsh environment such as the seaside, industrial service areas, etc. Other materials improve appearance with age, such as copper, timber, etc. Construction Detailing : Repairable surfaces & resistance to damage Plasterboard is inexpensive, easily patched and painted whenever its damaged. Hence used in many homes. Kitchen cupboards often have a toe recess, to hide broom marks and stuff.
Construction Detailing : Cleanable Surfaces Areas such as hospitals need easily cleaned surfaces, and avoiding corners that can catch dirt. Special consideration for even the shape of the corners have been thought of.
Construction Detailing : Maintenance Access High rise buildings and such tend to have huge maintenance access so that the damage that has occurred within the building can be easily repairable. Such as how the tiles can be removed and accessed conveniently.
Construction Detailing: Constructability If detail is difficult to construct, it’ll be expensive. Details should be easy, forgiving, based on efficient use of construction facility, tools and labour. Otherwise it’ll be extremely expensive, from parts, size, equipment and accessibility, it can affect the cost greatly. Composite Materials:
Materials: Monolithic or Composite? Monolithic materials are: -A single material, or -Materials combined so that components are indistinguishable
Composite materials are: -Two or more materials combined in such a way that the individual materials remain easily distinguishable
Composite materials are formed from 1. Combination of materials which differ in composition or form 2. Remain bonded together 3. Retain their identities and properties 4. Act together to provide specific synergistic characteristics not obtainable by and of the original components acting alone Composite materials can be grouped into 4 main types 1. Fibrous (products containing discontinuous or continuous fibres) 2. Laminar (sandwich panels) 3. Particulate (gravel and resins) 4. Hybrid (combinations of two or more composite types) Composite Materials –Fibre Reinforced Cement (FRC)
Made from - cellulose fibres, Portland cement, sand and water Common forms – Sheet and board products (commonly called FC sheet) and shaped products such as pipes, roof tiles, etc Common Uses – Cladding for exterior or interior walls, floor panels Benefits – Fierce cement building materials will not burn, are resistant to permanent water and termite damage, and resistant to rotting and warping. It is a reasonably inexpensive material Composite Materials - Fibreglass
Made from – Mixture of glass fibres and epoxy resins (glass fibres often used in a fabric or tape form) Common forms – Flat and profiled sheet products and formed/shaped products Common Uses –Transparent/translucent roof/wall cladding and for performed shaped products such as water tanks, baths, swimming pools, etc Benefits – Fibreglass materials are fire resistant, weatherproof, relatively light weight and strong Composite Materials – Aluminum Sheet Composites
Made from – Aluminium and plastic Common forms – Plastic care of phenolic resin (or a honeycomb sheet) lined with two external skins of thin aluminium sheet Common Uses – As a feature cladding material in interior and exterior applications
Benefits – Reduced amounts of aluminium are required and lighter weight, less expensive sheets can be produced, which are weather resistant, unbreakable and shock resistant. A variety of finishes can be specified and ‘seamless’ details can be achieved with careful cutting, folding, bending and fixing. Composite Materials - Timber Composites
Made from – combinations of solid timber, engineered timber, galvanized pressed steel Common forms – Timber top on bottom chords with gal. steel or engineered board/plywood webs Common Uses – Beams (floor joist and roof rafters) and trusses Benefits - Minimum amount of material is used for maximum efficiency, cost effective, easy to install, easy to accommodate services Composite Materials - Fibre Reinforced Polymers
Made from – Polymers (plastic) with timber, glass or carbon fibres Common forms – Often associated with moulded or pultrusion processed products Common Uses – Decking (& external cladding), structural elements such as beams and columns for public pedestrian bridges using glass or carbon fibres, carbon fibre reinforced polymer rebar Benefits – High strength FRP materials with glass or carbon fibre reinforcements provide a strength to weight ratio greater than steel. FRP composite materials are corrosion resistant Movement Joints
All building materials expand and contract in response to normal changes in temperature. Some also swell and shrink with changes in moisture content, while others deflect under to occur in order to prevent distortion, cracking, or breaks in the building materials. Movement joints should provide a complete separation of material and allow free movement while, at the same time, maintaining the weather tightness of the construction Types of movement joints
Expansion Joints - continuous, unobstructed slots constructed between two parts of a building or structure permitting thermal or moisture expansion to occur without damage to either part. Control Joints – continuous grooves or separations formed in concrete ground slabs and concrete masonry walls to form a plane of weakness and thus regulate the location and amount of cracking resulting from drying shrinkage, thermal stresses, or structural movement Isolation Joints – divide a large or geometrically complex structure into sections so that differential movement or settlement can occur between the parts.
Activity of the week Site visit
This building has 3 floors, it has reinforced concrete glass and panel. It’s concrete roof is for a possibility of another floor in the future, and also the shape of the building is made in such a way for it to align with another one of the buildings next door For buildings to maintain its green star ratings, it cant be very high level buildings, usually at max it would only be 3-4 storeys high. The building is north facing after takinginto considerations of the solar heat gains, steel frames are build around the perimeter of the building for sunshades
The area we entered through is supposedly an area where the toilets are to be built.
The concrete being used has a green star rating of 5, instead of being made of 100% materials, it is made of confliash and broken down concrete. It’s a recycled material, hence it took longer to allow it to fully form
There are many pipes already installed within the building. The red pipes are for fire, the white pipes are for plumbing and the cables installed are for the electricity. The ceilings in these areas come to the edge of a beam
Though the landscape within the building is uneven, by the end of the construction, several layers will be added to the floor to make sure that it stays at the same level. The timber being used for that floor requires more thickness to buildup than tiles would An area showing the services being hidden, such as the cables that connects the air conditioning and heating. The double studs in the walls allow for the pipes to go underneath,, and is also for the sill to look wide, making it look more stable and sfe
An area where folded doors are to be fitted into. The construction workers were very clear on what was being built around here
A ‘hole’ in the ceiling to allow for air and exhaust to go through and up to the roof
As the building shape is serpentine, every room has a slightly different shape. Every room is being divided with double stud for acoustic separation, it allows for airspace and so it becomes sound proof. Though the building is serpentine, none of the walls are curved because of the costs and also that it is difficult to install doors for curved walls
There are holes in the beams because concretes are more exposed in these areas. To get services through, the beams are pierced
There are copper pipes for hydraulic panels sitting under the windows. On the top right side of these big windows, there is a pipe in the corner for air intake
Set downs for bathrooms and stuff have already been set in place, however for the time being, due to insufficient cost, the building will conclude with this as being its rooftop. Hence the floor is made of concrete. Sheets and timber are put into place and can be taken away later for negative space.
Bricks being used for the building has silicon based glazing done to it to give it the white texture in the surface of the brick.
Constructing Environments week #10 Definitions of key terms learnt this week Shear wall- a wall composed of braced panels to counter the effects of lateral load acting on a structure Soft story – A multi storey building with several floors that have windows, wide doors, large unobstructed commercial spaces or other openings in places where a shear wall would normally be required for stability as a matter of earthquake engineering design. Brace frame – A structural system which is designed primarily to resist wind and earthquake forces Life cycle – a technique that is used to estimate the total cost of ownership Latent defect – a fault in the property that could not have been discovered by a reasonably thorough inspection before the sale Fascia – A board or other flat piece of material covering the ends of raters or other fittings Corrosion – Deterioration of a metal as a result of chemical reaction with its environment IEQ – Indoor Environmental Quality : encompasses IAQ, thermal comfort, daylighting, views, etc. Lateral Supports -error in link given on e book journal-
Collapses and failures Building’s material selection was too wide, exposed to hot north sun, painted black on the outside and had fasteners , resulting in cracking -Consider exposure,
Heroes and Culprits Issue to consider when selecting materials -Health and IEQ -Waste/recycling/recycled -Energy use and embodied energy -Pollution -Life cycle Materials: Impacts Building materials are responsible for -30% of total raw materials use -42% of total energy use -25% of solid wastes -40% of atmospheric emissions 1% of products are used 6 months later Health (IEQ) -Reduced life span -Asthma/bronchitis
-Nausea -Headaches -Sick days -Comfort
How do you choose? Reduce VOCs -Paints/sealers/adhesives/particleboard/carpets Reduce particles/dust -Horizontal shelf/floor coverings/loose fibre products Green Cleaning Particles -Vaccumin/chemicals
Source and waste It’s wasteful, it costs money to buy, to replace, to dispose Limited resources, takes up spaces, places that can breed disease YOU SHOULD GO FOR Renewable/abundant resources -Agricultural products/earth/timber Timber -recycled/plantation/RFA Waste -reduce/reuse/recycle -maximize use of composites Energy -Climate change, greenhouse effect, global warming -Wasteful -Pollution from energy production YOU CAN MINIMIZE THIS BY Minimise embodied energy -Extraction/manufacture/transport Optimise lighting -general appliances Optimise appliances -Fridges/dishwashers/office equip
Pollution Smog, ozone layer depletion, acid rain, toxicity, radio activity, eutrification and nutrification, dioxins YOU CAN STOP THIS BY Minimise waste -choose materials that don’t contain toxins/natural materials/organic
*Looking for the best solution considering the longevity of materials, not just embodied energy, consider the timelessness of the materials, have it designed for durability, reuse, recyclability, maintenance, and purpose
A Tale of Corrosion Statue of Liberty -Copper skin is supported on an iron skeleton designed by Gustave Eiffel *Copper reacts with oxygen, causing it to dull, first becoming a darker brown colour then forming a green copper oxide patina
Initial connection detail consideration Galvanic corrosion between the copper skin and iron frame was considered at the time of construction and a solution that allowed for the separation of the two metals was devised
First solution The two materials were separated at their junctions by a layer of shellacimpregnated cloth The problem Over time, the shellac-impregnated cloth became porous and actually held moisture at the joint between the two different metals. This provided good conditions for galvanic corrosion and the iron began to corrode What happened? The connection system started to fail as the build up of corrosion products (rust) expanded and pulled the rivets away from the copper skin,. The second solution To overcome the problem, the original iron armature frame was replaced with a Teflon coated stainless steel structure. The selection of stainless steel was made after extensive corrosion resistance testing and consideration of the physical properties of the stainless steel and how well it would work with the existing copper skin The future The new system includes two different metals and so will require ongoing inspections and maintenance Activity
Making the drawing from week #08 into 3D
To ensure that the veracity of the drawing and to visualize how it would look like in 3d, another visit was made to the pavilion, and from there on, methods regarding how that section will look like in 3d became clear.
The section of the wall that was needed to be drawn in 3d is as follows
Constructing workshop on the 02/05/14 In the constructing workshop, I was assigned to group 2, where we were given the following materials 1200 X 3.2 X 90 mm Ply X 2 1200 X 42 X18 mm Pine X2
We had to make a structure spanning at least 1000mm and will take a point load of the centre with a maximum height of 400mm. At the same time it was appropriate to consider that structures should be a little over 1000mm so that the structure is able to sit over something properly.
These were the materials listed, along with several equipment that we used to help modify the length and width of the materials such as hammers, drills, saws, nails, etc.
This was the plan the group came up with. We also thought that more nails should be hammered into the top half of the structure to give it more bracing and stability.
Eventually, we managed to get structure worked as planned, however due to time constraints, we had not the chance to saw of the sides of the plywood, hence we had to put some spacing between the two pieces of pinewood to ensure its ability to be compressed.
We then proceeded to insert pressure into the structure that was built, with the ruler starting at 16.2 cm. It was a bit difficult balancing our structure due to the limited width it has, hence a huge block of wood was used to shorten the gap to allow the machine to work. However the block of wood itself wasn’t very stable and caused the structure to be bent at an unexpected angle.
The structure built started twisting at a side due to the inability for the load to be applied flatly
The resulting unexpected angle the pressure was extorted to cause the wood to crack and splinter. The final length of the measuring ruler was 20.5cm, and it showed to have managed to support as much as 360kg