Class activities
week 10 details drawing: section of rooftop A46-03
FINAL DRAWING
3D tracing
Knowledge map Week -10- Lateral support Wind act more effective on high and think buildings earthquake act as base structures 3 strategies: prevent the building from overturning from nature forces • bracings:and at the top of the building, put a bracing sheet Sheet bracing, again, reinforced the whole structure. Bracing, to make sure that the building will not clips
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shear wall, frame joists
wind loads • tall, thin buildings are effective by wind loads • building on a hill, move only one sides : resists by horizontal bracings, uses columns, bracings under the buildings • making the building more symmetrical •
tall buildings sometimes have soft stories basement, as designers wants to keep the first floor more open for customers, but then higher level will bearing a lots of loads: insert bracing in the buildings to
As sometimes the building want to keep the first floor open- soft story: the higher buildings may need to carry more loads
Strategies: Bracings in the buildings, and the soft story to prevent the buildings Wind loads clips
collapses and failures: •
timber fascia: wide and thin, timber, expose to the sun, painted black in one side: crapping
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and need to repair at, suffering in 12 months. Flat steel sheeting on plywood: coastal environment, sun exposure next to beach. Plywood can provide smooth. Is glue strong enough to stick plywood into timber? Is sheeting can be stick enough for longterm? Gap seal not good enough problems within 12 moths: 1. the mental sheets which facing the sun: north and west, are starting blister ( ): getting hot in the summer, the glue is not enough to hold the temperature, the plywood sheeting start to coming out vertical and horizontally: water gets in. 2.plywood is not stick longterm properly. Start getting out. 3. sheet fall off: wind go in, water gets in. 4. they changes to nail it. But still. Solution: waterproof plywood=> catting 12 mm long, joints will not strong enough. Considers: long term performers, exposure, compatibility strength and deflection, maintenance, constructions and detailing: smooth? outside of the buildings
heroes & culprits consideration: • health & IEQ: indoor environment question: DALY: reduced life space, headache, comfort ◦ paint: reduce VOC water based paint would be recommendation, reduce dust etc ◦ chemical: choose products ◦ villains: paints, glues, finishes, carpet ◦ HEROS: bamboo products: pre-finishes: no odors; cloths: DIY self-spray • waste/ recycling/recycled: ◦ reduce waste ◦ reduce costs ◦ renewable resources: timber, recyclable, ◦ villains: timber, tiles,limited spaces ◦ hero: grass, wallboard recycle timber, roof tile • energy use and embodied energy ◦ causes climate changes, greenhouse gas,pollutions ◦ minimize embodied energy ◦ villains: aluminum, light globe, ◦ hero: timber (low embodied) dio light globe • pollution: ◦ smog, ozone ◦ minimize waste : don’t contact toxic ◦ villains: PVC: no recyclable, cigarette ◦ heroes: polonium, wool: regulating moisture • life cycle ◦ timelessness material: how long to replaced it, easy to reuse, durability, green wash material impact • 30% of total raw materials • 42% energy use • ONLY 1% of material can be used after 6 months TALE OF CORROSION: the statue of liberty • history: designed by Auguste Bartholdi • copper skin is supported on an iron skeleton
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iron frame is the structure, and covered copper skin the rib is the connections, originally zinc materials, support the copper from clapping copper oxidization: exposed to the atmosphere => reacts with oxygen =>copper starts to golden, shining dull => becoming a darker brown => green copper oxide patina can use acid to removed, but green becoming identities initial connection detail consideration: Galvanic corrosion between the copper skin and iron frame (dissimilar metal),copper and iron contacted => corrosion. solutions: separated at their junctions by a layer of shellac-impregnated cloth fibre cloth stuck with vanish to stop the contact: start works well => porous and held moisture at the joint between two different metal => galvanic corrosion: zinc then connection system started to fail: rust => expanded and pulled the rivets away from the copper skin: copper to fall 2nd solution: removed iron armature frame: replaced by Teflon-coated stainless steel structure; after corrosion-resistant test => but still, the stainless steel with zinc have possibility have reaction.
Wind loads=> housing structure
wind wind
1. Wind exert + pressure horizontally on the windward vertical surface of a building : slope > 30degree 2. wind exert – pressure or suction on the sides and leeward surface of a building: slope< 30 degree
building materials •
brittle materials: low elastic limits and rupture under loads, less reserve strength < ductile, not suitable for structural purposes • stiffness: measure of the force required to push or pull a material to its elastic limit: span and deflection under loading consideration considerations:
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temperature and moisture with other materials exposed to weather or used in moist environment thermal conductivity density or hardness of a material => resistance to wear and abrasion durability in use and the costs not produce smoke and toxic gases color texture and scale of a material reduce unnecessary cutting or wasting of material
The closer the two materials are, the less likely they would happen reaction.
glossary week 10 • • • • • • • •
Shear wall: a wall of a structural frame intended to resist lateral forces, e.g earthquake, wind, and blast, acting in the plane or parallel to the plane of the wall Defect: any condition or characteristic that detracts from the appearance, strength or durability of an object Soft Storey : multi-story building with one or more floors which are soft due to the structural design: dangerous in earthquake => fail Fascia: a board used on the outside vertical face of a cornice/ the board connecting the top of the siding with the bottom of a soffit/ a board nailed across the ends of the rafters at the eaves Braced Frame: a wooden structural framing system in which all vertical members, except for corner posts, extend for one floor only. Corrosion: the oxidation or eating away of a metal or other material by exposure to chemical or electrochemical action such as rust. Lifecycle : used to describe the period of time that a building can be expected to actively and adequately serve its intended function. IEQ: INDOOR ENVIRONMENTAL QUALITY: an important criterion for green, sustainable, building design : general overall building occupant comfort. Incl. Humidity, ventilation and air circulation, acoustic and lighting.