AT2 Technology Portfolio by Thomas Fairbrother

AT2 Technology Portfolio Thomas Fairbrother 1006128

Building Failure exploration Materials and Energy in dwellings Part M and Stair design Ebbw vale detailing exercise Designing to reduce noise Structures around Cardiff Structural Strategy Lighting Analysis Construction Detailing

3-4 5 6 7-9 10 11-12 13-16 17-24 25-28

building failures Select and appraise 2 buildings in Cardiff .1 (new) building that is defect free, identifying where defects may occur and 1 (older) building with defects, identifying the defects and the cause. Identify defect and the cause of the failure and how it could be avoided.

Case 1:

Stadium House 5 Park Street, Cardiff.

A tower block currently owned by BT group. Has a steel structural systema and originally completed in 1976. Has recently undergone a refurbishment (2002) in which it recieved new aluminium cladding.

Over time, it is inevitable that building failure will occur. This could be due to many reasons. This could be poor design, bad worksmanship or a variety of environmental wear and tear. All vertical facades are flat therefore water run off will be an issue and rainwater will collect in crevaces between cladding panels across the entire structure. Throughout the facade the preventitive device is a rubber bonded sealant between panelling but the application has been careless and as such gaps are visable which will again contribute to rainwater collection within the facade. Here is just one example of the sealant already coming away due to poor worksmanship, creating access points behind the facade.

In this place, on the underside of one of the panels, there is a substantial aperture which although not so much open to water damage, may allow for infestation behind the facade by insects or allow spores and subsequently mould to grow on the unlaquered underside of the panelled facade. A further example of the poor worksmanship, again a potential site for water, or other damaging substances to get beneath the rainscreen cladding of this building.

Conclusions The main problem identified is the poor worksmanship on the

facade during the buildings latest refurbishment the facade over the coming months and years. The in immediate threat but if the defense system of will fasten the decay process of the unprotected more severe problems.

which exacerbates wear on internal structure is not the facade fails then this structure behind and cause

Identified possible failure: There is very poor worksmanship in the detailing of the newly installed exterior metal cladding system. The application of the seal is not uniform and there are places where gaps have not been sealed, making it suseptable to water damage. The thin laquer layer covering the metal will wear out due to UV radiationa and wind erosion and lead to staining of the cladding. How may this failure be avoided? Due to the nature fof the cladding system there is little one can do to wholly avoid the failure from happening as adhesive bonds and seals will always wear out. over time. However, the longevity of the cladding may be prolonged if the any gaps could be filled preventing water from getting behind the cladding. This potential failure could have been avoided by choosing a different system of cladding which did not rely on a plastic seal. for example ceramic tiling.

Case 2: Cardiff Central Train Station Central Square, Cardiff It is the largest and busiest station in Wales and one of the major stations of the British railway network. It was originally completed in 1976. However, it was rebuilt in 1932. It is a Grade II listed building managed by Arriva Trains Wales.

Lack of flashing allowing water to seep into joints between bricks could cause wall failure

Mould and moss growing due to damp

No water drainage system causing algae staining on the building details

The building has no system of water disposal from surfaces. The flat tablets only help to collect water and dew. AS Cardiff has such a wet climate, it is unsurprising that this design flaw has lead to damp and moss growth on the exterior. If this continues, the water will wear away the masonary joint and cause cracks to form where plants may begin to grow, leading to further, more structural, damage to the masonary. Problems of water getting into the building will also cause a hazard as damp will gradually reach the interior. The mould could lead to a health and safety hazrd to the transport users of the building. This building needs to be checked to see if the mould is starting to form in the cavity or in the insulation layers as this will lead to failure. Water drip details should be installed and a waterproof layer should protrude over teh apex of the roof to protect the masonary work.

materials and energy in dwellings To allow for maximum daylighting in each unit there is an atrium through the central core of the building. This means daylight can enter through the large glass wall on the exterior and reflected light from the central atrium. This set up also allows for natural ventilation through each dwelling unit.

Total Area: 272.263 m2 Floor Area: 87.874 m2 Volume: 212.151 m3

I have produced a basic 3d model of one standard dwelling unit in the masterplan for my housing scheme in order to test and analyse the energy performance of the space using ecotect. I will alter the material make up fo the structure to see how this may reduce energy costs in order for it to comply to part L of building standards 2010.

a standard floor plan taken from masterplan

Part L 2010 stipulates that u value of walls must be 0.3 W/m2.K and party walls 0.2 W/m2.K

Initial material selction for analysis

Standard glass 6mm Air gap 30mm Standard glass 6mm U-Value= 2.710 GAINS BREAKDOWN - All Visible Thermal Zones

1st January - 31st December

12.000

IN S ID E

Standard glass 8mm Air gap 20mm Standard glass 8mm Air gap 20mm Standard glass 8mm U-Value= 1.780 kWh/ m2

35.6%

12.000

GAINS BREAKDOWN - All Visible Thermal Zones

9.000

6.000 51.1%

3.000

0.000

Overall Gains/ Losses

3.000 6.000 9.000 12.000 14th

Jan Conduction

28th 14th Feb

28th 14th Mar Sol-Air

28th Apr

14th

28th 14th May Direct Solar

28th 14th 28th Jun Jul Ventilation

14th

28th 14th Aug Internal

28th 14th 28th Sep Oct Inter-Zonal

14th

28th 14th Nov

28th 14th Dec

MONTHLY HEATING/ COOLING LOADS - All Visible Thermal Zones

55.9%

6.000 16.4%

9.000

27.7%

12.000

28th

15.000

kW 2400.000 1800.000

1200.000

600.000

0.000

600.000

1200.000

1800.000

2400.000

Feb

Cooling

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

14th

Jan Conduction Cardiff, Wales - UK

1800.000

Jan Heating

16.2%

3.000

2400.000

3000.000

89.8%

6.000 3.000

0.000

Wood(pine) 15mm Polyisocyanurate board 100mm Air gap 80mm Plaster board 10mm U value =0.180

% 11.6%

9.000

15.000

O U T S ID E

Max Heating: 5.274 CATEGORY LOSSES GAINS kW at 07:00 on 6th ------------- ----December FABRIC 55.9% 0.0% SOL-AIR 0.0% 51.1% SOLAR 0.0% 1.6% MONTH HEATING(kWh) VENTILATION 16.4% 0.0% ----- ---------INTERNAL 0.0% 35.6% Jan 2025.448 INTER-ZONAL 27.7% 11.6% Feb 1312.434 In the previous wall Mar 1158.133 make up there was a wood Apr 1203.320 structural system and May 194.193 the plasterboard facing Jun 68.646 the internal space but Jul 0.000 no dedicated insulation Aug 0.000 material, just a cavity. Sep 113.373 This meant that all air Oct 692.941 heated inside the space Nov 1705.722 was being lost through Dec 1997.016 the fabric of the ----- --------building. TOTAL 10471.226 ----- --------PER MÂ˛ 119.162 Floor Area: 87.874 m2

Conclusion

By inserting a 100mm layer of YEARLY GAINS BREAKDOWN MONTHLY HEAT LOADS polyisocyanurate to the wall LOSSES GAINS make up and an extra sheet of Max Heating: 2.817 CATEGORY ------ ----- glazing, the energy kW at 07:00 on 6th --------FABRIC 16.2% 0.0% consumption has reduced from December SOL-AIR 0.0% 5.7% 119 kwh/m2 to 58 kwh/m2 per SOLAR 0.0% 4.5% year. MONTH HEATING(kWh) VENTILATION 72.1% 0.1% ----- --------INTERNAL 0.0% 89.8% This is still above the Jan 1010.905 INTER-ZONAL 11.7% 0.0% requirements for a low energy Feb 617.384 home(~30kwh/m2). It is due I chose polyisocyanruate thermal losses through the Mar 562.455 to insulate the because large window but this has the Apr 618.005 it offers the best May 93.893 positive of letting in good thermal insulation per Jun 15.514 amounts of daylight and will unit thickness. It is in reduce the need for artificial Jul 0.000 a board form and so Aug 0.000 lighting during the day. would be easy to work Sep 51.108 and give uniform Oct 322.362 The conduction/fabric losses coverage. It is Nov 815.981 have been severely reduced. and sustainable because it Dec 963.915 the internal gains increased. is an inorganic material The majority of the energy to ----- --------and so less likely to TOTAL 5071.521 heat the space is being used to rot as an organic ----- --------counteract the ventilation of insulator may and so PER MÂ˛ 57.714 the space. A heat recovery Floor Area: 87.874 m2will be less likely to system may help recuperate some be replaced in the of the heat lost through buildings lifetime. ventilation and reduce the 1st January - 31st December % yearly energy consumption.

Overall Gains/ Losses

kWh/ m2

YEARLY GAINS BREAKDOWN

IN S ID E

O U T S ID E

Wood (pine)15mm Air gap 80mm Plaster board 10mm U-Value=2.350

Revised material selction for analysis

O U T S ID E

IN S ID E

O U T S ID E

MONTHLY HEAT LOADS

one individual dwelling unit

Dec

3000.000

28th 14th Feb

28th 14th Mar Sol-Air

28th Apr

14th

28th 14th May Direct Solar

28th 14th 28th Jun Jul Ventilation

14th

28th 14th Aug Internal

28th 14th 28th Sep Oct Inter-Zonal

14th

28th 14th Nov

28th 14th Dec

MONTHLY HEATING/ COOLING LOADS - All Visible Thermal Zones

Jan Heating

Feb

Cooling

Mar

Apr

72.1%

11.7%

The findings from this investigation suggest that if the window was reduced in size or segmented with strips of more insulative materials then the energy performance increased and perhaps get nearer to being a low carbon house.

28th

Cardiff, Wales - UK

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

polyisocyanurate board 5

fire and circulation 4

The main circulation through the building is via the lifts as it is a high rise development. There are stairs through the centre of the centre of the building as way of a fire escape or if people are travelling only aThere few are floors. The iscentre ofa minumum 4 lifts, each of at least the building is technically an exterior space as there is a void through the centre size of 1100 x 1400mm and their controls to aid ventilation. The main circulation through the building is via the lifts as it is a

fire and circulation

400mm from the door which opens on the highare rise 4 development. There theminumum centre of size the of There lifts, each isare ofstairs at through least a 1100corridor. x 1400mm and their circular The corridor is 2m wide centre of the building way of a fire escape or if people arecircular travcontrols 400mm from as the door which opens on the corridor. corridorcorridor is which complies The with minimum 2m wide which complies corridor widthsanof 1.8m and allows for 800mm elling only a few floors. Thewith centreminimum of the building is technically widths of 1.8m and allows for 800mm clear clear space in front of lift doors and a 1500 x 1500 landing. exterior space as there is a void through the centre to aid ventilaAccess does not discriminate between disbaled and non disabled tion. people. There is the same circulation all. at all Access does not discriminate between disbaled forThe widthEntrance between inner columns at the levels is done so that there are no ramps or stairs to negotiate. and non disabled people. There is the same circucentre of the building is 1.2m. This gives The width between inner columns at the centre of the building is lation for all. Entrance at all levels is done so that enough room for min entrance width of 1.2m. This gives enough room for min entrance width of 1000mm. there are no ramps or stairs to negotiate. 1000mm.

The central stairs are in flights of 16 steps, which is acceptable as the going is over 350mm. The width of the staircase is 1.2m to The centralfor stairspassing are in flights of 16 steps, is acceptable going is over 350mm. allow space according towhich regs. There isasathe generous landing between flight. steps will have corduroy The width of theeach staircase is 1.2mThe to allow space for passing according tolandings regs. There is a genand the contrast in The material tread so that it edges is erousedges landingwill between each flight. steps willwith have the corduroy landings and the will visable to visually impaired.

Underground car park level Underground car park level

Ground entrance level Ground entrance level

contrast in material with the tread so that it is visable to visually impaired. Housing unit Housing unitstudy study

1:100

Upper floor housing level

1:100

1:1000

There is a porch area at the entrance to the dwelling so that space in the corridor is not taken up by people opening their doors. Although there is not min width of There is a porch area at entrance to the dwelling so is private stairs I the have decided that 750mm that space in thewidth corridortois not taken up by to people sufficient gain access the mezzanine level. There there is sufficient opening their doors. Although is not min width of headroom(more than 2.1m) below the upper private stairs I have decided that 750mm is sufficient stairs for people to walk under to increase width to gain access to the level. There suffiflooor space and themezzanine stairs double upisas storage space for downstairs. cient headroom(more than 2.1m) below the upper stairs

for people to walk under to increase flooor space and the

Upper floor housing level

1:500

1:500 6

ERC building

structural and tectonic design detailing 1 The ground on which the building sits is not very stable due to its previous use as an industrial site, so a raft foundation was preferable. This ensures that any movement is even and prevents uneven stress on structural elements.

1 Concrete raft foundations

2 Hot rolled steel beams provide ventilation space below the structure.

2 The building needed to be raised from the ground to allow ventilation to the wooden structure and in case of flooding and this is done with hot rolled steel beams.

3 ty unnos Welsh Sitka spruce post and beam structural system in filled with poly-insulation and fire retardant spray coating.

3 The main structure constitutes ty unnos post and beam system. Beams are made from low grade welsh Sitka spruce in a box cross section and filled with insulation to create a composite material which minimises heat losses. 4 The floors and walls are made from panels of plyboard adhered to rigid poly insulation material.

4 Spruce plywood Structurally Insulated Panels (SIPS) with fire retardant spray coating. U-value of 0.15 W/m2K

5 The glazed facade is made of triple glazed panes to lower the thermal losses and allow daylight into the classroom during the day. 6 The glazing is covered with a layer of charred louvers. These act as a shading device to reduce solar glare. They are mounted on hinged casements so that they can be opened in the summer to allow the classroom to expand outside. The wood is charred to protect the wood in case of arson attacks and to weathering by providing an oxidised layer.

Sketch of a SIPS panel

5 Triple glazed glass windows with printed design. 6 Charred batten louvers on hinges

7 rubber seal

7 The entire structure is encased in an airtight rubber seal. This waterproofs the building also. There is a cold formed steel roof above to shed the majority of the rainfall but this is an extra layer to ensure a good seal.

4 7

3 2

toilets

classroom space

circulation space

office space

storage and services

1 There are 2 layers of plasterboard to given a sturdiness to the wall and protect the vapour barrier enclosing the house but also because it has good thermal properties. 2 Service void allows apace for cabling etc and leaves a gap between the plasterboard and the important air tight seal. 3 This supports the ladder beams providing strengthening to the wall so that there can be a large amount of cellulose insulation. 4 These tie together the two OSB and span the cellulose insulation space 5 This has good insulation properties, lowering the u value for the entire wall and is recycled material 6 This has the best insulation properties for the thickness of the insulation, again contributing to the low u value of the wall.

Ty Unnos house

7 Due to the rigidness of the insulation board the render can be directly applied. This sheds off any driving rain and protects the insulation. 8 This directs any collecting water away from the building. The edge incorporates a drip detail to shed the water more easily. It is a galvanised steel to give is protection from the elements. 9 Triple glazing minimises thermal losses and allows natural light into the building. There are few north facing windows to prevent any thermal losses. The largest glazing is on the south facade to allow any solar gain if it happens to be sunny. The windows act as anatural ventilation device in case there is an abnormal heatwave but they will be rarely used in the a passive house. 10 This acts as a protective cap for the wall below the window to and a shelf to put things on. Perhaps a plant? 11 The Intello membrane is key to the buildings success. It offers high diffusion tightness in winter (protects against condensation) and maximum diffusion openness in summer

9 10

5 7

23 4 6 stairca bathroom entrance hall

front door

1 2x12mm plasterboard 2 70mm service void 3 37mm orientated Strand Board 4 210mm Sitka spruce ladder beam 5 270mm Infill warmcell cellulose insulation 6 100mm rigid board polyisocyanurate insulation 7 Directly applied white render. 8 Metal exterior window sill 9 Triple glazed windows with insulated cases. 10 Sycamore interior window sill 11 Intello membrane

The situation of marrying new with old can be a challenging project but is one wihich offers great architecural possibilities. The ebbw vale office building is one of such projects and I will analyse and sepcify how the architects of this project have dealt with the situation on this occasion.

Ebbw Vale Office Building -

At this junction in the building a new wall and two supporting posts for the steel staircase meet the exterior of the old office building.

This junction is at the point of entrance between from the existing old building and the new extension. The sketch shows the multitude of columns cluttering the space and the unusable gap between the two structures.

There is no architectural continuity in the new extension. The treatment at places where new meets old varies a lot throughout. The positioning of the columns of the new extension appears to be random and not thought through. Perhaps a few of the columns could be replaced with just one? Also, the size and shaping of columns is clumsy. Some are thin and coated obviously purely structural elements but when a socket is required, the columns are clad from floor to ceiling in generic boxing. The fixtures and fittings do not respect the old building and are installed wherever is most convenient, in a quick retrofit fashion. There are missing bolts on the staircase. Although not required structurally, it would be more pleasing for them to be fitted. This is due most probably because of careless workmanship. Also, the amount of steelwork in the staircase is unnecessary. the job of transporting people to an upper level could have been done with less material and perhaps in a more lightweight fashion, have a lighter touch on the older building. The headroom is also very minimal, suggesting that the design has been rushed and not thoroughly checked before building. The choice of colour scheme seems cold and sterile. This may be deliberate, to contrast with the old building, but resembles a place more like a laboratory or hospital. The amount of circulation is large. The circulation could have been enlarged slightly to leave usable dwelling spaces and give 9 more of an open plan feel.

designing to reduce noise 8

Calculation of Reverberation Time Housing Unit acoustic exercise

Room volume: Surface/contents

5 G

1:50 technical section of dwelling showing wall makeup

1:100 floor plans of housing unit

Area 125 Hz

1. Hot rolled steel primary structural skeleton, infilled with poly-insulation material. 2. Cold formed steel secondary structure. 3. Reinforced concrete ground floor slab 4. 60mm Polished screed floor finish 5. Concrete floor plate infilled with insulation 6. 250mm Polyisocyanurate board insulation 7. 2x12mm Plasterboard with soundproof mat between 8. 2mm Steel sheet treated with a weather resistant coating.

FLOOR concrete CEILING plasterboard WINDOWS glazing SIDE AND FRONT WALLS plasterboard REAR WALL plasterboard SEATS None AUDIENCE Empty 2/3rd full Full TOTAL ROOM ABSORPTION - A Room empty Room 2/3rds full Room full REVERBERATION TIMES Room empty Room 2/3rds full Room full

500 Hz

2000 Hz

a (coefficient) Sabins a (coefficient) Sabins a (coefficient) Sabins

m2 6

75m3

31.4

0.01

0.314

0.15

4.71

0.02

0.628

0.3

10.5

0.1

3.5

0.04

1.4

15.36

0.35

5.376

0.18

2.7648

0.07

1.0752

0.3

0.1

0.004

0.16

3.84

0.3

1.152

0.1

0.384

0.004

0.01536

0 (each)

people

0 250 800

(each)

0 0 0

29.342 29.342 29.342

15.3588 15.3588 15.3588

3.27856 3.27856 3.27856

0.41 0.41 0.41

0.78 0.78 0.78

3.66 3.66 3.66

The reverberation time for the space at 125hz is 0.41 seconds. The reverberation time for the space at 500hz is 0.78 seconds. The reverberation time for the space at 2000hz is 3.66 seconds. Under empty circumstances, this means that the space would be suitable for speech as the 500hzvalue is between 0.7 an 1.0. It would be less suitable for music as the 500hz value is less than 1.2seconds. Once the room is occupied the reverberation time will decrease. This would reduce the RT for frequencies above 500hz an improve speech intelligibility.

Each housing unit in the tower is connected to a main core and cantillevers out meaning that the unit is technically surrounded by a layer of air. Thus, there will be no direct transmittance of noise from one unit to another through the fabric of the walls. However there is still a possiblity of noise reching the another unit so an absorbant or resilient layer is required. This additional element will help to block any noise that may travel from a surrounding unit or from the circulation corridor adjoining the unit. Because the walls are already clad in plasterboard it makes sense to find a noise soluiton which can be easily Typical 1:500 floor plan integrated with this material. I would suggest sandwiching a soundproof mat between the plasterboards to do the job, as this would ensure that all facets of the unit ,apart from floor and window are protected. Although not prescribed to block noise the 240mm of insulation will aid the noise protection.

Churchill House

Expressed Structure

10 floor office building with retail on the ground floor. Prefabricated concrete frame construction with brick infill. The repeated prefabricated cruciform concrete motif facade forms the architectural expression of the building. It indicates the direction of forces moving through the frame, emphasising the forces moving horizontally and then vertically through columns to the foundations. There is greater mass of concrete at points where force lines meet.

I have highlighted the primary structure of the frame/facade in red. Theses are the members where most of the forces are acting. It can be read as the main load paths.

This detail shows how loads are transferred to the primary columns of the structure from the secondary elements and to the foundations.

Cardiff Central Library

Connection

6 floor library building + restaurants on ground floor Hybrid conrete/steel/timber frame construction The connection is in compression and the plate angled in order for forces to be transferred vertically to the column, necessary due to the pitch of the roof.

Morgan Arcade

Transfer Structure

Structure housing retail units Load bearing wall structure with structural steel spanning elements. In this case a transfer structure has been implemented to keep the circulation free below whilst supporting the newer structure above. The load path diagram below shows how the gravitational force of the brick wall of the structure above is carried to the load bearing walls either side, transferring forces from vertically to horizontally through the supporting steel beam.

I enjoy how the concrete column has been capped neatly, giving the impression that this column is entirely cylindrical and how it tapers to appropriate the scale of the timber joints and flitch plates. The cap is reminiscent of the tapered eraser pencil toppers one can buy, which seems fitting for an academic environment.

the Level @ Barry Structural Proposal

The proposal consists of several elements: A series of 4 â&#x20AC;&#x153;shedsâ&#x20AC;? housing rehearsal rooms, box office, cafe, admin and temporary gallery space A subterranean theatre with foyer and other servant spaces A tower to provide water and light to the theatre below and accomodate a contemplation room and viewing platform. A stage workshop housed in an existing sturcture on the site. (A circulation/ service spine connects the buildings to one another.) I will explain the structure of the sheds, the subterranean theatre and tower in more detail on the following pages.

Site ground conditions

1Sheds These were conceived of as a series of 4 structural shells to provide basic shelter from the elements and their form takes precedent from that of the vernacular buildings found around welsh mines. Conceptually the idea is one of contrast; that one side of the sheds would act as a heavy backdrop for the public space and that the other would be seem light and float above the ground. Secondary structure would be added to fill these shells when necessary in order to provide insulation and partition the buildings into rooms. The â&#x20AC;&#x2DC;shellsâ&#x20AC;&#x2122; would be based on a steel portal frame system anchored to the ground by concrete raft foundations. There would need to be strong moment connections where the vertical wall meets the roof. The steel frame would be embedded into the concrete wall to add resistance to buckling and to add mass to the counterweight. The frame would consist of the same frame repeated at 6m intervals and aligned perpendicular to the wall so that forces are distributed uniformly. As well as taking the dead load the shells must resist the wind loads which will cause the roofs to deflect up and down. It is important that the moment connections are sufficiently large enough to cope with these loads.

Single storey rigid frame typical span 9-60m I am spanning 10m so that is within the typical span range. Typical L/d= 35-40 I will use 35 as the sturcture is already working hard. 10000/35=285.7mm I will round this to 305mm after referring to the UB beaam table. I will double this value for the vertical element to 533mm, as it is having to work twice as hard as a usual frame system and to accomodate large moment connections.

T moment C

C moment

Spacing of frames = l/4 or l/6 Again I will choose the most conservative value when calculating spacings between frames. 10000/6=1666.67mm 12000/1666.67=7.19 =7 frames Concrete wall and foundations The structural frame will be stiffened and braced by being embedded in an in situ cast concrete wall and foundations. The wall will share the gravity loads and the foundations will act as counterweight to add mass to the foot of the frame. The raft foundations are 800mm deep so that they lie below the line of frost action and to ensure sufficient counterweight.

moment

Moment connection needs to cope with great moment forces

2Subterranean

theatre

Following the conceptual idea of the typology of welsh coal mines, the main space of the proposal, the theatre is suitably found below ground. The maximum depth is 10 metres below ground. The excavated soil will be used to create a slope on the west side of the site. There are also existing retaining walls along the south side of greenwood street. Secant piling would be used as retaining walls. All piles are located at least 600mm from any existing structures around the site to allow the piling machinery room to operate. Piles would be drilled to the full 10 metres but earth excavated in 2 stages. The first 5m would be excavated and then props employed to span the width and temporarily aid the retaining walls whilst the lower 5m is excavated. Then the lower concrete walls would be erected in situ using concrete and once gone off the props would be removed in order to allow the top 5m of concrete structure to be poured. I have designed the subterranean spaces with structural nesting in mind so that the interior walls act as permanent props and able to withstand the lateral loads from the surrounding earth. I wish to leave the secant wall exposed to the interior space on one side. I do not anticipate too much water penetration due to the compactness of the soil substrate and interlocking of the secant piling. However what water does seep through I intend to deal with the removal inside the structure through internal drains. The rest of the walls will all be waterproofed to prevent water penetration. I have allowed for 1m topping to the underground space to make up to ground level so that there is ample depth for spanning between load bearing walls. As I am proposing to build beneath the road, the 1m deep â&#x20AC;&#x2DC;roofâ&#x20AC;&#x2122; will accommodate any service ducts that were previously running below the road.

The RC infill acts as diaphragm to add stability to the structure. Reinforced two way slabs Typical spans 6-11m Maximum span in structure=11m so a suitable method of spanning Typical L/d - 28-35 d=11/30=0.36666m=366.66mm round to nearest multiple of 25=375mm As it is underground there is a requirement already to cover the bottom of the structure with concrete and a waterproof layer. Also, it need not be too thick as the ground conditions are very stiff and it is far below the frost level.

C C

C C C

3Tower The tower will be a steel frame structure. The tower is located directly above the main auditorium space so the concrete walls and foundations below can act as foundations for the tower. It will just need to be anchored to the concrete structure. There will be cross bracing on the upper half of the tower but I want it to feel open below so wan tot refrain from adding expressed cross bracing below. Instead the stairs leading up the tower will act as cross bracing for the lower section. I will ensure that the vertical primary elements are of square cross section to resist buckling in both lateral directions. There is an additional tower to accommodate a lift tot eh side of the tower. It will be made of a simple vertical truss system and again anchored to the concrete foundations below. The infill above will add rigidity and the floor will act as a diaphragm to resist shear movements. The main risk will be torsional effects on the tower due to wind loads but hopefully the lower bracing hidden by the stairs will be sufficient to prevent this.

C or T

Wind

C or T

Diagonal truss tube for lift tower The tower needs to be 9/10 storeys tall. but lateral restraint halfway up so H actually is equivalent to 6/7 storeys. Typical height 60-110 storeys. W=2000mm typical H/W is 5-7 to check 20000/2000=10 so structure is going to be working hard. It will be braced by the main tower by walkways from the lift tower. To make it more stable I could increase W 20000/2800=7.1

Main tower Rolled steel hollow section Typical heights Single storey 2-8m Multistory 2-4 These are small values and I need to reach 20m. I have already increased the torsional stiffness by using closed instead of open section steel but have the main issue of buckling.

This is too great for what I would like so I may have to use a lattice column. They have greater typical heights 4-10m with h/d of 20-25 I will end up with a similar depth but it will be perforated so will have a seemingly lighter appearance.

I do not want to add any more steel as cross bracing or support below so the only option is to create weighty large sectional steel members. h/d between lateral supports is 7-28 for multi storey but there are buckling and compression issues if the value is above 20. I shall use the value of 20 to calculate my depth. 20000/20=1000 My steel will need to have a depth of 1000mm. But this could be a risky 715mm if issues are addressed.

Digital and Physical Lighting Analysis

In this Lighting study I will be analysing, quantitatively and qualitatively, the lighting levels in the main space of my design project. The space I have chosen is the main auditorium in my theatre complex. It is situated below ground level. The need for light is only to light the stage below ground level evenly and so that direct sunlight and glare is avoided. In a theatrical environment there can be a great variation in lux levels required depending on the nature of the performance. A director may wish for there to be great or little amounts of light so long as there is enough to see what is going on. I would say that the minimum value of lux would be around 100 lux incident of actors on stage. I therefore will be aiming to allow for achieving a contrast of lighting in the space and illustrate that there is possibility for this variation.

I began the lighting experimentation through physical model. My design led to there being a 10 x 10m hole above the theatre and I needed to get light into the space below. I addressed this initially with a simple thin grid but found this let in too much daylight. I tweaked the design of this grid by deepening it and angling it so that it reduced the amount of daylight and so that it cut out the direct light getting into the space below which could have had problems with glare for audience members. I model this at 1:25 and tested it in the artificial sky. I used a physical light meter to get lux readings and work out daylight levels. My readings suggested that I was getting DF of 0.01-0.2% which seemed to be very low. I will hope for better results in my digital model.

Main Auditorium Lighting Analysis Physical Model

While I had access to the sky I altered the time of day to see varying amounts of daylight in the auditorium and to see the qualitative effects on the space.

Daylight

I also tried covering up a number of quadrants and use small LED torch to imitate artificial lighting on the space. I liked the silhouette effect of the grid and the variation of lighting possible in the space. It seemed to echo the design ideas of subterranean coal mines and this sort of theatrical space fits well.

Artificial

Artificial 19

To the left is one of my preliminary renders of my digital model. In this model I was aiming to replicate the lighting I achieved in my physical model. I did however encounter problems with getting an even distribution of light over the wall surfaces. The quality of light in the physical model proves far more accurate than the digital model. It gives a warmer more realistic image. However, although I had these difficulties, It was satisfying to find the same sort of effect in the digital model as in the physical. In both The 3m overhang around the sky grid was enough to shade partly the seating and audience and the grid worked well to block out the direct sunlight into the auditorium. One difference between the digital model and physical is the selection of material. In the physical model I used just 2mm grey cardboard for both sky grid and concrete walls. In the digital model I could specify medium rust steel for the sky grid and a rough concrete for the RC walls and floor slabs. Again, the lighting is similar in both images so from this we can conclude that the grey card worked well, reflectively, to replicate concrete. The digital model does show how the colour of the steel material surface alters when light is incident upon it whereas the physical model does not.

Daylit with inserted stage

Daylit without inserted stage

Artificially lit with inserted stage

Artificially lit without inserted stage

Referring back to the cover page, I am aiming for a variation and contrast in lighting possible in the theatre. You can see this achieved in the rendered images. This model includes extra steel as a framework for the gallery and as an inserted stage. The addition of a plywood stage helps to reflect light around the theatre. You can see this in the reflections in the steel mesh in the top left corner of the image. It is necessary only to light the actors on stage, which is achieved in both arrangements and lighting conditions. Elsewhere in the theatre it is acceptable to have darker conditions, in fact this may be preferable. I am pleased with the quality of light achievable during day and night. There is a good lighting on the stage for the actors and the rest of theatre encompasses the lighting above ground, an indication of what is going on above the stage- which is another design aim. Hence to the grid acting as an interface between eh real world and the subterranean theatrical world.

I have selected the day lit and artificially lit digital models to compare quantitatively the lighting.

Here is the artificially lit setup on the digital model. You can see the concentration of lux levels at the centre of the auditorium This time levels are as much as 100 times less than the day lit scene but In my opinion has a far more theatrical setting. Also, as this is fed by artificial lighting above there is no variation in position of the lighting and it can be entirely prescribed by the director of a production.

In the day lit image on the left the lighting is far more evenly distributed and the lux levels far higher. This is because it is essentially open to the sky and so the lighting conditions are as are outside presently. In the lighting analysis grid below you can see the light falling most in the centre of the stage and reducing further out, Desirable for such an in the round auditorium arrangement.

The lights used in this model are

The daylight settings are also shown below. The lighting is not entirely central due to the angle of the sun and so throughout the day the peak lux levels will be found at varying central points.

not taken from ERCO as I am using exterior t h e a t r i c a l lights an I could not find files for ERCO equivalents. I therefore have used a spherical u n i f o r m distributed photometric light and a s p o t l i g h t positioned 10m above the grid to light the theatre. 24

In order to show the detailing with sufficient clarity I am showing the section in 3 parts, illustrated on the subsequent 3 A1 sheets.

In more detail, this is through the external viewing deck at the top of the tower, through an insulated internal viewing deck/ writing room and water collection tank, through the artificial lighting fixing grid, through an angled light reflecting interface and then through the uninsulated theatre space below and its foundations.

I have taken my construction detail section through my tower from roof to foundations.

Thomas Fairbrother

roof to foundations

Tower

Construction Detailing

1:50

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ade

m o

I have used thin aerogel insulation in this case to cover up a potential cold bridge at the corners of the roof. To reduce costs this material could just be used to cover up the gaps and a more traditional insulator used to fill in the cavity between structural beams.

It also shows how water is directed from the roof to the water collection tank.

This drawing shows the layering of the facade. Outermost an LED screen to advertise and communicate with the public, then a white gauze to add privacy but allow views out from the tower, then glazing.

a 120x100x12mm steel handrail b 2mm white fabric gauze c LED screen d 8x70mm steel fascia e 10mm steel bolt f 160x115x12mm profiled steel beam for water run off g 100x12mm steelgrid h 30mm glazing i 2mm lead sheeting j 6mm spacetherm aerogel insulation k 12mm ply board l 260x280x20mm structural steel beam m 20mm plasterboard n 50mm recessed steel bolt o 280x120x20 structural steel I beam p 50x50x8mm steel cage q 300x300x24mm steel square section bracing r24mm ply board

nijkl

abcd

f h

a b c d e f g h i j k l

10mm steel bolt 2mm white fabric gauze LED screen 8x70mm steel fascia 100x12mm steel grid 12mm anti-theft steel grid 30mm structural steel grid and light reflector 60mm steel infill panel 60mm glassinfill panel 1000mm in-situ reinforced concrete 180x100x12mm steel handrail/beam 12mm perforated steel plate

This drawing shows how the tower meets the ground level. There is a permanent structural steel grid integrated into the reinforcement for the concrete which reflects light into the auditorium below and blocks direct sunlight from entering. Above is a thinner grid whose purpose is to lock in the replaceable infill panels which can be either opaque, transparent or void to allow variation in lighting conditions for the auditorium. The grid is in no way waterproofing or insulation as the idea is that water, collected from above, can rain down onto the grid and through it to the theatre. Drainage is explained in the next drawing.The balcony around the auditorium is also shown.

a b c d e f g

This drawing shows how the tower structure meets the foundations. It also shows how the lightweight steel inserted stage can be easily disassembled if needed to allow for a sunken stage setup. It also shows how the water would be disposed off through the drains at the edges of the stage. I have no pitch on the floor so that water is allowed to collect for artistic effect. Water can be easily swept to the side when needed. The auditorium is plenty below ground so no need for insulation and the foundations should be plenty thick enough as the ground conditions are very solid at this depth. I have included a layer waterproofness between the clay and the concrete to reduce water penetration.

24mm ply board 50x50x8mm steel stage framework and stools 300mm reinforced concrete floor slab and wall steel grid over water channel 1000mm concrete raft foundations 2mm waterproof membrane very hard clay