Week 3
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Week 3 Learning Summary Key Structural Elements
Footing and Foundation Ching (2008) defines foundations as a substructure that’s constructed partially or fully in the ground to support the super structure. Footings support the loads from the super structure and don’t over exceed the bearing capacity of the soil. If the loads are greater than the soil can handle the footing system will sink. The type of soil present on site determines what type of footings and foundations will be used. There are two types of footings and foundations which are shallow footings and deep foundations. Shallow footings such as pad footings, strip footings and raft (mat) foundations are used when the soil is stable. Whereas, deep foundations such as end bearing piles and friction piles are used when the soil is unstable and the support needs to run further down to where the soil is stable.
Strut- Good for compression (e.g. Column)
Mass construction materials Masonry- clay bricks –Types of courses
Brick joints
Stone- limestone – good for carving shaping
Tie- Good for tension, narrow thing material (e.g. Cable ties) Beam- will undergo compression and tension (e.g. timber, steel and reinforced concrete Slab/plate- loads can be spread across slab or broken down between spans (see image above)
Concrete blocks – holes in concrete allow for reinforcement rods to be installed
Panel walls- walls can also carry and transfer loads Shear diaphragm- act as a bracing system prevent building from overturning
Equilibrium –moment = force x perpendicular distance 9
Week 3 Studio This week’s studio consisted of a tour of some of the University of Melbourne’s structures. We looked at how the structure was made, their structural systems and types of materials.
South Lawn Underground Car park
The tour started at the loft 6 cafe which has a skeletal structural system. The structure is made from concrete which is a non modular material that is dense, hard and not flexible (Newton, 2014). The size of the columns suggests it was built in situ (which means it was cured on site) as they would have been too big to bring in by truck. The assumption can also be gathered by the texture of the concrete; the texture wasn’t completely smooth which implies it was constructed on site, as precast materials are usually very smooth.
Concrete performs effectively under compression making it the ideal material for this structure as it is supporting massive dead (soil, trees, structure) and live loads (people, events). The concrete is also reinforced with steel allowing it to be equally good for tensile forces.
As shown in the image there is a gap between the funnel section and the column. This shows two stages of construction as well as acting as a control joint allowing room for expansion and contraction of the concrete structure.
Due to the large span of the funnel columns and ceiling the structure would have been built in situ. The funnel columns were designed to allow for the above ground trees root systems to grow, which also suggests the funnel section of the column is hollow.
On our way to the next structure we came across this expansion joint made out of silicone. This joint allows for the expansion and contraction between the bricks preventing the structure from cracking. 10
Week 3 Studio Old Quad
Arts West Student Centre This structure consists of a large truss beaming out and across over the walkway which is supported by a massive block.
Truss load path:
The truss is also supporting to beams (that run through the building) that is sits on as it is balancing out the load path. This structure is made from limestone which is an ideal material for carving and shaping. Although the material is aesthetically useful and pleasing, it is also a more weak material making it vulnerable to damages. The structure has recently undergone conservation to repair the weathering damages which attest to this. The majority of the structure is held in place by weight and gravity and some mortar. Due to this structural system the vaults tend to want to spread and to prevent this, an additional support has been added to the back of the vaults columns. Even though this structure is quite large, there is reason to believe that this truss was constructed with precast parts and assembled on site as there are visible welding marks, yet the material is too smooth to be in situ.
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Week 3 Studio Beaurepaire Centre
Oval Pavilion This structure has been constructed with several materials including timber (non-structural elementcladding for cantilever), concrete (structural- flooring and ceiling) and steel (structural- inside timber cladding of cantilever, frame of building, cantilever columns).
The cantilever is mainly supported by the central steel columns. And as the below image shows, the cantilever overlaps the building but doesn’t use it as support.
This structural system is very different from the load bearing structure of the old quad through both aesthetics and form. This structure makes it very difficult to understand its system as it is concealed behind the exterior. Surprisingly the structure isn’t supported by the steel frame but rather by the hidden caballing in the interior that resist horizontal loads.
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Glossary Cladding: covering or coating over structures Diaphragm: thin sheet of material Equilibrium: centre of gravity/ physical balance Substructure: lowest part of a building In Situ: materials formed on site and not prefabricated
References Ching, F. D.K. (2008). Building Construction illustrated. Hoboken, NJ: John Wiley & Sons, Inc. Newton. C. (2014) W03_m5 CONCRETE BLOCKS. Retrieved from https://www.youtube.com/watch?v=geJv5wZQtRQ&fea ture=youtu.be
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