KNOWLEGE MAP week 5 – FRAMING
RIGID FRAME: is described as a frame is capable of resisting both forces and moments by its joints and columns. It can bearing loads produce axial, bending, and sheer forces in all members of the frame. • •
Fixed frame (rigid frame): connected to its supports with fixed joints. Hinged frame: connected to its supports with pin joints: prevent high bending stresses from developing by allowing the frame to ratotate.
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three- hinged frame: assembly of two rigid section connected to each other with pin joints; least affected by support settlements and thermal stresses
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any opening in a load bearing wall weakens its structural integrity.
Therefore under the linter must have an opening that support the load bearing, in order to let the load transfer from the top to the bottom
Timber system: • • • • • • • • • •
hardness: medium-low. Reasonably easily marked fragility: medium-low. Not easily shatter or break, not like glasses ductility: low. Some can be manipulated into a range of shapes high flexibility and medium plasticity protected carefully density are depends poor conducted with electricity and heat, very durable recycle, reuse, very useful and desirable cost are depends for product country
consideration when using timber: • size- depth X breath ◦ make sure specific size beforehand ◦ length (0.3 meter increments). Commonly max 6 meter- longer lengths in limited size • season timber- furniture, flooring, not variation, harder timber >15% unseasoned • not all timber types are available • wood to timber: knots- weak points// cause slope of grain • bottom bend would be tension • Isolate timber from INSECT attack: chemical barriers • protect timber from Sunlight and Heat: direct sunlight can cause excessive drying shrinkage; breaks down wood; cellulose light color paints are best • hazards: fire/ chemical exposure
wall structure system •
structural frame: ◦ concrete frames: rigid column with beams into frames, qualify as noncombustible 不燃 的，fire-resistive construction, larger buildings ◦ steel frames: keep dead loads down, use a grid of steel columns connected to steel girders and beams, stabilized using wall sheeting or bracing, I-BEAMS UC; CIRCLE BEAMS CHS, RECTANGLE BEAMS, industrial buildings,
◦ timber frames(above): diagonal bracing or shear planes to stabilize the structure, less common, slopping sides, uses a grid of timber POSTS or POLES connected to timber beams ◦ concrete and steel frame are able to span greater distances and carry heavier loads than timber. ◦ Structural frames can support and accept a variety of nonbearing or curtain wall systems •
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load bearing walls: ◦ concrete: new designing buildings, ◦ masonry :load bearing wall can be constructed from Core filled hallow concrete blocks of GROUT 灌浆 FILLED cavity masonry. BOND BEAMS over openings can be created using special concrete blocks which filled with concrete to bond the individual units together. Lintel: Filled with gout or concrete ◦ both walls qualify as noncombustible, and rely on their mass for their load0caring capability ◦ while strong in compression, both walls require reinforcing to handle tensile 可拉力的 stresses solid masonry: ◦ load bearing wall with single or multiple skins of concrete units or clay bricks ◦ garage, frames = two skins, waterproof sheets flashing that allow water to go through ◦ head showing face concrete brick ◦ lintel- steel cavity masonry: ◦ two skins of masonry ◦ advans: better thermal performance and opportunity for insulation whthin the cavity, ◦ better waterproofing ◦ the presence of a DAMP PROOF COURSE and WHEEP HOLES in a wall are indicators that the wall is a cavity wall rather than a solid wall. Inside of two wall: flashing ◦ stud walls,common timber of steel ◦ light gauge steel framing ◦ timber framing ◦ stud carry vertical loads while sheathing or diagonal bracing stiffens the plane of the wall ◦ can accept a variety of interior and exterior wall finishes finish materials determine the fire-resistance rating of the wall assembly ◦ onsite OR off site ◦ flexible in form ◦ efficient, diagonal or sheet bracing is needed. Top plate bracings Vertical stud noggins Bottom plates
Ply bracing
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Brick veneer construction ◦ combined of 1 skin of non-structural masonry + 1 skin of structural frame wall Loads carrying down to joist
Brick system tide to stud work Non structural skin
columns:
Description
Short columns
Long columns
Shorter, thicker cross-section
Taller- thinner cross-section
Sketch each column type
Length >12:1 Lengths <12:1 = short eg. 3000mm tall column with a 450mm X 300mm crosssection= 10:1 How does each type of column Compressive load is applied crashing/fail
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Bulking. Middle of the columns bulking outwards. How they fixed the column with the top and the bottom determinate how much load can carry.
Plywood: an engineered sheet product and used for structural bracing OSB board: made from timber chips wax and resin weekly mystery material: Multicell poly carbonate ◦ when sunlights get in, it will become different colour, very costly, fixed with alumni cover, expand widely strong. Plastic. ◦ 1. light- admitting quality 2. heat preservation:reduce heat in summer and keep warm in winter 3.difficult to burn 4. anti-impact 5.guards against the ultraviolet ray antiResource:http://www.alibaba.com/product-detail/lexan-polycarbonateaging honeycomb-sheet-Heatguard-multicell_627611788.html 6.sound-insulated 7.easy to install