Constructing Environments Logbook Week 5 Summary
Construction Challenge This week’s construction challenge concentrated on the group’s ability to construct a section of the Oval Pavilion canopy. This is quite a detailed build. At first we constructed the main structural bearing member, the spine truss that runs along the centre of the structure. This transfers the majority of the load to the foundations.
When assessing the structures ability to transfer loads it becomes quite apparent just how complex this build is.
Initially we attempted to construct the model out of some ply wood, we quickly discovered it was a bad idea as the material was far too difficult to cut through. After a few other issues with materials we kept with soft balsa wood and sticky tape for the joins. Once the main spine truss was completed we moved onto the shorter trusses projecting out of the side. We measured the details as best we could from the scales supplied however there were a few small adjustments that needed to be made in order for some of the members to fit correctly.
Side truss
Samuel Hill
Constructing Environments: Week 2 Logbook
Student Number: 722052
Nil support When comparing it to the other students’ models it become apparent that a small error or adjustment in the design can have consequences when attempting to assemble all the various pieces.
As the structure was being assembled a few of the joins were not aligned, while only minor measurements they had the capacity to cause a big issue. If this had occurred on site it would have had disastrous consequences for the builder and architect. It would have required almost a complete rebuild if the desired outcome could not be achieved. The structure we completed was not able to support itself. It required additional support to the side. It was very strong when stressed in the East West direction however would topple over when left unsupported. The working drawings call for it to be attached at the building edge.
Looking over the Spine truss towards the west side of the canopy. Showing tendency to topple due to no support along the East West line of the truss.
Final section of the truss.
Samuel Hill
Constructing Environments: Week 2 Logbook
Student Number: 722052
Learning Log Structural Frame - Concrete Frames
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Typically use a grid of columns with concrete beams connecting the columns together Steel Frames
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Gird of steel columns connected to steel girders and beams, braced with diagonal steel members Timber Frames (post and beam)
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Uses grid of timber posts or poles connected to timber beams Bracing of members between bays or at the corners is required to stabilise the structure
Load Bearing Walls - Concrete
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In situ or precast elements Masonry
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Core filled hollow concrete blocks Bond beams over openings, used as alternative to steel or concrete lintels. Solid masonry created using single or multiple skins of masonry units Skins are tied together using a brick or with metal wall ties.
Stud Walls
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Light Gauge Steel & Timber Framing
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Smaller sections require nogging to prevent long thin members from buckling Brick Veneer
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Bricks carry no load
Short Column - <12:1 Fail due to crushing â&#x20AC;&#x201C; when the compressive strength is exceeded. Long Column - >12:1 Fail due to buckling â&#x20AC;&#x201C; fixing determine where they will buckle and how much load they will carry.
(Ching, 2014)
Samuel Hill
Constructing Environments: Week 2 Logbook
Student Number: 722052
Glossary of terms Stud:
Fixed to top plate and bottom plate, responsible for transferring the majority of the load from above in a stud frame construction.
Nogging:
Cross members designed to provide additional strength to a stud frame construction. As long thin members are prone to failure by buckling, nogging is introduced to a frame to assist with countering lateral forces.
Lintel: 窶連ny opening in a load bearing wall weakens its structural integrity. A lintel or arch must support the load above a door or window opening and allow compressive stresses to flow around the opening to adjacent sections of the wall (Ching, Page 2.14).
Seasoned Timber:
In order to maximise timbers structural properties it is dried to a certain point. Classified as seasoned timber when it has less the 15% moisture content. Process reduces to approx. 12%.
(Ching, 2014)
Buckling: When a long slender column is subject to a load that exceeds its bearing capacity it most likely fail due to pickling rather than crushing
will
Axial Load: A stress placed on a structure along its main axis.
Reference List Ching, F, D, K. (2014). Building Construction Illustrated. Hoboken, New Jersey: John Wiley & Sons. Samuel Hill
Constructing Environments: Week 2 Logbook
Student Number: 722052