Week 05 Summary
Column
Buckling Direction
Engineered Timber Solid products: LVL, glulam, CLT Sheet products: plywood, MDF, chipboard & strandboard Other manufactured products: I beam Box beams Timber flanged steel web joist
>1:12 short Crushing <1:12 Long Buckling
Wall System Structural Frame: concrete frame, steel frame,timber frame(post&beam) Load Bearing Wall: concrete Masonry – reinforced cavity solid
Stud Wall: light gauge steel framing, timber framing, stud framing (top plates/ vertical studs/ noggins/ cross bracing/ ply bracing), Brick veneer (1skin-non structural masonry + 1 skin structural frame wall)
Wood to Timber Early wood – rapid growth, large cells, light color. Late wood – slow growth, lack of water, dark color. Growth – one ring per year Grain Direction: strong parallel&stiff parallel
Weak perpendicular to grain Seasoning – process of removing water from wood - 15% moisture contends. •To adjust moisture Soft wood Hard wood: Quarter sawn •Provide stability Radiata pine Ash Cypress pine Gum Back sawn •Air drying – cheap, slow Hoop pine Jarrah •Kiln drying – 20-40hrs to dry to 12% Dounglass fir Oak Radial sawn •Solar kiln – less expensive Balsawood KNOTS – WEAK POINT
第 # 期:[日期] Studio Report(Structural Concepts)
折页册
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Material Materials: •Balsa sheets – columns, beams •Masking tape – joints Characteristic: Balsa •Lightweight – reduce the loads when construct frame. •Easy to cut (parallel to grain) – shape the required columns and beams efficiently. Masking Tape •Quicker – allows the connection to be fixed in the shortest time.
Process The assigned part of our group was the eastern skylight of the Oval Pavilion according to the pavilion drawing set; refer to structural drawing which shows the structure behind the wall, we determine the skylight has a column and beam construction system and a skeletal structural system. Therefore we decided to use balsa to build the frame.
The section drawing on the right and below states the eastern skylight in a larger scale where we could easily determine the structure elements. The skylight is comprised by struts, beams and cantilever, also we noticed there were marks on the plan like B8, C10, etc.
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Studio Report(Structural Concepts) 第 # 期:[日期]
折页册
By reading the legend, we found out that we needed 4 C3, 3 C10, since we were only making the eastern skylight; they were made to support the whole model vertically. For the beams, we needed 6 C3, 8 B8, 12 B15, moreover, in order to tie the frame, we also need roof bracing and wall bracing.
Joints are all fixed joint, since the pin joint allow elements to rotation around the pin in this case. We cut the balsa sheet into sticks and glued them by superglue at first. Later we found out that superglue didn’t stand well, and since we’ve run out of time by figuring out how to read the plan. We changed glue to masking tape since it was much easier and faster. C3: 100x100x4.0 Square Hallow Section.
B8: 150 Parallel Flange Channel, C shape, horizontal side is the halflength of vertical side.
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第 # 期:[日期] Studio Report(Structural Concepts)
折页册
The load path diagram on the left shows how applied load been transferred to the ground. Since the assigned part was part of the roof, the loads are mainly come from the structure itself rather than the elements inside. Also we joined our assigned part with the other half, which is shown below,
Comparison with Other group
The picture on the left is the eastern canopy, the picture on the right is the whole canopy, groups that were assigned to build it joined their work together by the end. They both used balsa sheets and sticks, and the joints were all fixed joints, unlike ours, they were assigned to built a significant cantilever which required to be strongly supported, therefore the columns should be thicker and provide more support to the cantilever. The load path diagram on the left image shows how loads transfer from cantilever to the ground.