THE UNIVERSITY OF MELBOURNE
Constructing Environments Log Book Final Submission Name : Trishya John Student ID Number: 699579
Contents Week 1 – Introduction to Construction ........................................................................................... 2 Week 2 – Structural Loads and Forces ......................................................................................... 13 Week 3 – Footings and Foundations ............................................................................................. 24 Week 4 – Floor Systems and Horizontal Elements ...................................................................... 57 Week 5 – Columns, Grids and Wall Systems ............................................................................... 81 Week 6 – Spanning and Enclosing Space ..................................................................................... 96 Week 7 – Detailing Strategies 1.................................................................................................. 107 Week 8 - Openings...................................................................................................................... 115 Week 9 – Detailing Strategies 2.................................................................................................. 132 Week 10 – When things go wrong.............................................................................................. 152 Glossary of Terms ....................................................................................................................... 162 Reference List ............................................................................................................................. 182 Appendix ..................................................................................................................................... 187
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Week 1 – Introduction to Construction Knowledge maps Loads on buildings (Ching, 2008)
Structural forces (Newton, 2014)
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Materials (Newton, 2014)
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Site Analysis (Ching, 2008)
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Theatre Session
We were introduced to the concept of loads on buildings in our first theatre session where we were given a single sheet of blank A4 paper and tape and asked to build a structure that can support a brick using only those materials. I formed a four point structure as shown below, which I strengthened by folding repetitively. I was unable to test the structure at the lecture, so I performed a test once I got back home by checking if the paper structure was able to support the load of all my textbooks. Shape allows an even distribution of the load of the textbooks throughout the structure
It was able to support my textbooks when the thicker side of the structure made contact with the ground, but not when the thinner side made contact with the ground. One of the things that I was able to learn from this experience was that it was crucial for a structure to have a very strong base in order to support an immense load. I also realized that one of the reasons why my structure was successful was because the symmetrical shape of it may have enabled an even distribution of the load of the textbooks throughout the structure. These were some of the key elements that I tried to apply to our structure that was built during the studio session.
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Studio Session Construction procedure
In our first studio session we were divided into groups of 3 and given blocks of the same size and shape made of MDF. As this was a compression challenge, blocks were an efficient building unit as blocks are commonly used in structures that rely on compression forces, such as arches. We were then told to make a tower as tall as possible that could accommodate a toy horse provided by our tutor, which meant that we had to integrate an opening into our structure. Our first step was to measure how high the opening had to be for the object to be able to enter the structure, and we did so by stacking the blocks one on top of each other next to the horse until they were a bit taller than the horse. However, we then realized that constructing the tower by placing the blocks as shown on the left would result in a structure that was very likely to collapse due to its instability, so we then decided to place the blocks flat on top of each other as shown below. We then had to re-estimate the height of the horse using the height shown in the image on the left. Estimating height of the object
Re-estimating height of the object
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We then decided to slightly change the laying of the blocks and place them the conventional way bricks were laid in a building instead of merely stacking them one on top of each other. This would have been more stable than originally planned, as the load from a block will be transferred to two bricks below it instead of just one and thus be spread out more evenly. Original block laying technique
Modified block laying technique
Aimed height of the opening
Foundation of the structure
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We then started to build the structure as shown below. Our aim was to pack the blocks as tightly as possible in the first ten rows to create a stable base and then decide on how to change the way the blocks were laid once the structure gained a reasonable height. Packing the blocks tightly together will result in more blocks being laid at the base, which then increases the compression forces, causing the blocks to be compact. This is what will ensure stability for the whole structure.
However, this layout of the structure had to be changed once again. This was because the object had to be rotated once it was inside the building in order to make it fit inside the structure. Therefore, there was a risk of the structure collapsing if we rotated the horse while sending it into the opening. Details of the block laying technique – high compression forces due to tightly packed blocks
We then decided to remove the blocks from one side of the structure to form an opening as shown below and covered the gap made in the original building. This would then resolve the issue of the object being able to enter the structure without having to be rotated.
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Modified layout to accommodate object
Even though we had now developed a structure that could accommodate the object, we still faced the issue of bridging the gap created in order to form a doorway. We attempted to stack the blocks in a ‘staircase’ manner on either side, but the blocks fell after about two or three of them were placed, due to the increasing load and the inability of the blocks to support them, so we were unable to create a bridge as the gap was too wide.
Our next idea was to warp the structure in order to bring the gap closer so that a fewer amount of blocks would have to be used in order to form a bridge.
Warping structure – decreases compression forces at base
Attempt at building a bridge
We attempted to bridge this much smaller gap by stacking the bricks in a similar manner to before, but unfortunately we were unsuccessful again. As we could not make the gap smaller, we decided to focus on making the structure as tall as possible. Due to the limit on the amount of MDF blocks we were given, we decided to use less blocks to build the rest of the structure. I was able to conclude that due to the fact that the blocks were packed tightly for approximately twelve rows, the base would be strong enough to produce a stable structure that was capable of supporting a heavy load. I based my conclusion on the paper structure I made in lecture 1, which was thick at the bottom due to the folds, and thus was able to support the weight of all my books. We then continued to lay the blocks on the structure, but left large gaps in between so that we would be 9
left with more blocks to add height. As the blocks are now spread out towards the top, the compression forces of the structure decrease with the height. Figure 1: Increasing the height of the structure
We completed our structure by following the same pattern established previously.
Final structure
Deconstruction procedure Doorway – did not collapse due to distribution of loads through the structure
Figure 2: Structure during deconstruction process
We were then told to remove blocks from the structure one at a time in order to test the stability of the building. In the process, I was able to find a method to create a doorway. Although we had considered this idea before, we did not think it would work as we assumed that the structure would collapse, and we only realized that it would have worked during the deconstruction process. I simply removed all the blocks in one area and created a large gap, as seen on the left.
Compression decreases with height as blocks are spaced widely
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The fact that our structure did not collapse even though all those blocks were removed indicates that the loads were transferred through the structure in a manner that was able to prevent the structure from collapsing. It is possible that our structure may have been able to support a heavier load, if it had remained in a rectangular shape. This final structure may have encountered difficulties with doing so because warping the structure pushed the blocks out of proportion in the base, which may have reduced the compression forces that would have been much stronger if the blocks were packed tightly together. Figure 3: Load path diagram of structure with a few blocks removed
Figure 4: Comparison of compression forces between original structure and warped structure
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Comparison with other groups
This group had built a structure that was most similar to ours in terms of the way they laid the blocks, and the fact that they packed the blocks tightly for the first few rows and incorporated gaps in the higher rows. The only differences were the shape of the building and the fact that they had managed to successfully integrate a doorway into their structure.
Strong compression forces enabled structure to support a load of over 5kg, which was done near the end of the studio session
This was another structure created by one of the groups, which had a very different block laying technique and shape compared to the structures of the other groups. It seems as though their technique of laying blocks, although aesthetically appealing, may have used a relatively larger amount of blocks compared to the conventional brick laying technique that all the other groups adapted. Even though their structure was able to accommodate the object, they too appeared to be unsuccessful in bridging the gap.
The blocks are packed tightly together, which will increase the compression forces in the structure
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Although the block laying technique is not very visible in this photograph, it appears that they adopted a similar method to our structure. However, it appears that they might have encountered difficulties during the construction process as they too were unsuccessful in creating a doorway, and were not able to create a tall structure. The blocks appear to be packed tightly together and they have followed this method to create the entire structure, which means that the compression forces will be high.
Week 2 – Structural Loads and Forces Knowledge maps Structural joints (Newton, 2014)
Structural systems (Newton, 2014)
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Common Environmentally Sustainable Design Strategies (Newton, 2014)
Building systems (Ching, 2008)
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Theatre session We covered the importance of how trusses and a bracing system are key elements in supporting loads in various structures. This was illustrated by various students having to build a truss on a plastic cup with straws which had to be attached to the cup with pins. These are diagrams of two structures that were made during this exercise, one which was successful and one which was not. Successful structure This structure was able to support a load effectively because bending the straws provided 8 paths for the load to be transferred to the ground. Folding also provided a much shorter distance for the loads to travel, and ensured structural stability.
Unsuccessful structure This structure was unable to support a load because the long straws were unable to support a load easily, which caused the whole structure to collapse. There were also only four paths for the load to be transferred.
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How unsuccessful structure can be improved
The unsuccessful structure can be improved by introducing a bracing system as shown in the figure above. The system is in the shape of triangles, which is a difficult shape to distort, and therefore adds more stability to the system. It also provides more paths for the loads to be transferred to the ground. The concepts illustrated in the lecture were useful for the frame challenge in the studio session, as they illustrated the different ways in which long, thin members could be used to effectively carry and transfer loads.
Studio session Construction procedure This week’s studio introduced the concept of a frame structure, and to illustrate this, we were told to build a frame tower out of only 20 strips of cut balsa wood in groups of 3. The tower had to be as tall as possible, and we were encouraged to experiment with different types of joints. We were told that the towers would have a load placed on it once they were completed to see at which points they fail. Balsa wood was an efficient material for this challenge as the strips were light and had a low density, which are properties that would have been needed to make a frame structure. In order to save strips of balsa wood, we decided to make the tower in the shape of a triangle instead of a square or rectangle. We cut 3 pieces of wood, of 20cm each, and used them to form an equilateral triangle for the base. Then, we joined three strips of wood to each of the corners of the triangle.
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Sketch of structure we wanted
Foundation of structure
We then cut a second triangle with sides measuring 20cm and joined it with the three strips of wood that were stuck onto the first triangle.
The strips of wood were joined together by masking tape, which, in the context of this structure, can be considered a fixed joint. A fixed joint resists rotation and translation in any direction, and provides force and moment resistance (Ching, 2008), and as the structure was relatively stable with an additional successive level, we decided to continue using fixed joints.
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However, as the structure began to increase in height, we found that we had to add pins to the joints, thus creating pin joints, along with the fixed joints, as strips of joined balsa wood kept detaching, which suggested that just fixed joints were not strong enough to hold the members together. We joined the strips of wood with a pin, and then wrapped the pin with masking tape. Fixed joint
Details of fixed joint
Structure is stable but a slight tilt can be observed due to weak joints
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Although we assumed that our combination of pin and fixed joints Details of pin joint were strong enough to keep the members in place, the tower began to twist and lean as it increased in height, possibly due to the increasing load of the structure. This was an indication that perhaps the joints may have not been efficient enough to transfer the loads, possibly due to the way we had attached the members. The manner in which forces are transferred from one structural element to the next and how a structural system performs depends on the types of joints used, to a large extent (Ching, 2008). The addition of the pin may have also caused the member to fold backwards, based on the way we attached it, which may have also been a factor in causing the structure to twist because the joints were not stable enough to transfer the loads.
The members were also rectangular in shape, which results in uneven distribution of the load through the strips of balsa wood. This would have also been one of the factors that caused the torsion of the member, resulting in the whole structure twisting. If the members were in the shape of a square, there would have been a more even distribution of the load, resulting in less torsion. Load through individual members
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Load path diagram of structure
As seen in this diagram, each joint will be connected to three members and will thus receive loads in three directions. If the joint is ineffective in transferring these loads, the whole structure will be unstable.
Due to the structure twisting and bending as a result of the joints failing, there came a point where the structure was unable to stand without support because it was unable to transfer the load effectively throughout the structure, which resulted in it being unable to support the load of the additional members. This explains why the final structure was unable to stand without support
Our idea was to form a bracing system in order to prevent the members from twisting, so we cut a strip of balsa wood and connected it to two of the members that were twisting the most. However, it did not fix the problem since the twists were due to the joints, so we did not continue developing a bracing system.
Attempt at bracing structure 20
Lean in the structure can be observed clearly due to the increasing load
We finally added 3 more members to the 3rd triangle (excluding triangle made for the base) and joined them at the ends. These are images of the final structure which was, as seen below, unable to stand without being supported. Structure without a support system
Point at which structure was unable to support itself
Structure with a support system
Deconstruction procedure The structures then had a load applied to them, in order to estimate at which points they started to fail. Figure 5: Deconstruction procedure
As seen in the picture, the structure was bending at the joints when a load was applied. It was mentioned before that the purpose of a fixed joint was to prevent rotation of the members, but ours failed to do so because we connected the members incorrectly. This was why the structure was bending at the joints.
Bending occurring at the joints when a load is applied – joint should have resisted load
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Load path diagram of a section of structure during deconstruction process As the load increased, one of the members that were joined at the second triangle snapped at its mid-point. This was because the increasing load was causing an increase in the reaction force that was acting on the member. The two forces met at the middle, which then caused the structure to snap at that point.
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Comparison with other groups All of the structures built by the other groups had a member snap at its mid-point when a load was applied, due to the explanation given. However, as seen below, the members did not bend at the joints the way they did in our structure, because they consisted of more effective joints.
Less bending occurs at the structural joints when a load is applied – only the individual members bend. Structures all displayed a bracing system that would have reinforced the overall stability.
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Week 3 – Footings and Foundations Knowledge Maps Structural elements and concepts Figure 6: Structural Elements (Newton, 2014)
Figure 7: Structural concepts (Newton, 2014)
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Construction systems Figure 8: Footings and foundations (Ching, 2008) (Newton, 2014)
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Materials Figure 9: Mass Materials (Newton, 2014)
Figure 10: Mass Construction (Newton, 2014)
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Figure 11: Bricks (Newton, 2014)
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Figure 12: Properties of bricks (Newton, 2014)
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Figure 13: Concrete (Newton, 2014)
Figure 14: Properties of concrete (Newton, 2014)
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Figure 15: Stone (Newton, 2014)
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Figure 16: Properties of stone (Newton, 2014)
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Theatre Session Figure 17: Olympic Games Park
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Studio report In the studio session, we examined the features of different buildings, such as the structural elements, structural systems, joints and materials. The buildings were:
Lot 6 Café Underground carpark and South Lawn Arts West Student Centre Stairs on west end of Student Union North Court Union House Beaurepaire Centre Pool Oval Pavilion (north side of Oval) Old Geology South Lecture Theatre Entry Structure Frank Tate Pavilion
Lot 6 Café Figure 18: Location of Lot 6 Café (The University of Melbourne, 2012)
The Lot 6 Café is located to the south of the Eastern Resource Centre, at the 1888 Building.
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Structural elements The ceiling of the café was supported by a beam which extended outside the building and was supported by a brick column outside the café. The beam and the brick column are both load bearing – the ceiling transfers loads to the beam, which will then transfer them to the brick column, which transfers them to the ground. Figure 19: Beam supporting ceiling (Design. City. Living., 2012)
Beam supporting ceiling inside the cafe
Figure 20: Beam supported by brick column (Design. City. Living., 2012)
Beam supported by a brick column outside the building
Brick column
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Figure 21: Load path diagram of beam
The beam supports the load of the ceiling and transfers these loads to the brick column outside
Figure 22: Load path diagram of column
Beam from the cafĂŠ transfers loads to the column, which transfers loads to the ground
Column transfers load to the ground
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Building Systems The main types of building systems that can be observed are the enclosure system, the structural system and the mechanical system. The enclosure system consists of walls that are made of concrete panels and glass, along with glass doors to provide physical access. There is also a flat roof which forms a part of the enclosure system that cannot be observed in the images, which may be made of concrete. Figure 23: Lot 6 Cafe Exterior
Glass and concrete forming a part of the enclosure system
The services that can be observed from the outside are the electrical system, seen through the lights on the concrete panels.
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Materials The main materials used in this building are concrete, glass, steel and clay bricks. Glass and concrete were used to form the enclosure system of the building, with glass being used more than concrete. This was done to allow the entry of natural light into the cafĂŠ in order to minimize energy consumption through lights. Concrete may have been chosen as it has an excellent thermal mass, which reduces energy needs from heating and air conditioning (Cement Sustainability Initiative, 2012). As seen in the diagram below, beams undergo both compression and tension. Mass materials such as clay or concrete will not be suitable for a beam as they are strong in compression but weak in tension. Therefore, steel was chosen as it has the ability to support both tension and compression (Newton, 2014) Figure 24: Forces acting on a beam
Bricks were used to construct the load bearing column that supports the steel beam. As columns experience compressive forces (Newton, 2014) , clay bricks were chosen to build the column as they are strong in compression (Newton, 2014). Figure 25: Column
Compression forces experienced by column
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Underground car park and South Lawn
Figure 26: South Lawn Car Park (The University of Melbourne, 2012)
The underground car park is located below the South Lawn, within close proximity to the Baillieu Library and the Brownless Biomedical Library. It was designed by engineering and planning practice Loder and Bayly. Excavation work began in May 1971 and the car park was complete by November 1972 (Lovell Chen Architecture & Heritage Consultants, 2011). Structural Elements The car park consists of load bearing concrete columns which are evenly spaced. Figure 27: Typical column
Upper column cap joined to the ceiling above
Column drum – joined to upper column cap with fixed joint Concrete pad footing
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Construction systems The enclosure system consists of reinforced concrete panel walls, along with a concrete ceiling. There are three pedestrian entrances and one entrance for vehicular access, but no windows as the car park is underground (Lovell Chen Architecture & Heritage Consultants, 2011). The storm water drainage system from the south lawn consists of 4 inch PVC downpipes integrated into the centre of each concrete column throughout the Car Park's structural grid. These downpipes discharge water into large ducts that run east-west in every second bay (Lovell Chen Architecture & Heritage Consultants, 2011). Figure 28: Method of drainage (Lovell Chen Architecture & Heritage Consultants, 2011)
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Materials The main material used in the car park is concrete. Concrete is a strong material which is capable of supporting many different types of loads. It is used to build the panels in order to support the ground pressure that will be exerted on the car park as it is built underground. It is used for the roof to support the dead and live loads of the South Lawn and is used for the columns for the same purpose. Figure 29: Loads of underground carpark
However, due to the South Lawn being directly above the car park, water from the soil has caused efflorescence in the concrete. This decreases the aesthetic quality of the concrete. This may have been avoided by adding more than one drainage pipe in each column which will enable the removal of more excess water from the soil. Figure 30: Efflorescence
Efflorescence caused by water from soil
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Arts West Student Centre Figure 31: Location of the Arts West Student Centre (The University of Melbourne, 2012)
The arts west student centre is located close to the zoology building and the babel building. Structural elements The main structural elements visible are beams, which are fixed at only one end to form a cantilever. They provide additional support to the loads of the large steel structure above it. Figure 32: Structural elements
Cantilever supports load of structure above
Structural supports at the two sides – will not be enough to support entire structure without the additional beams 41
Materials Figure 33: Timber beams
Timber beams joined together by a smaller beam, which increases efficiency as a support system Steel structure supported by timber beams – galvanized to prevent corrosion
In the image above, it can be seen that the beams are made of timber, and they are actually two thinner beams that have been joined together with a smaller steel beam. This will reinforce the supports and make them more effective in bearing the load of the larger steel structure. The steel will also be galvanized to prevent corrosion. The beams have also been placed as shown below in order to prevent bending. Figure 34: Placing of beams
Beams are not placed in this manner, as more surface are receives the load, which may cause bending
Beams placed in this manner, as less surface are receives the load, which minimizes bending
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Stairs on west end of student union
Structural elements The main structural element seen was beams which supported the load of the stairs and were fixed onto the brick wall. Figure 35: Stairway with supporting beams
Beams – support the load of the stairs
The cables that are connected to the beams appear to be ties which are tension elements. However, as it is the beams that are the load bearing elements, it seems that the cables are simply put in place to appear as though the stairs are suspended. However, they do provide lateral stability to the stairs by supporting the beams as seen below.
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Figure 36: Cables
Beams fixed to the brick wall
Cables provide lateral stability by supporting beams but do not bear the load of the stairs
Structural joints
In this instance, a fixed joint will be used to connect the beam to the brick wall, in order to avoid rotation and translation of the beam. Figure 37: Fixed joint between beam and wall
Fixed joint between beam and wall needed to prevent rotation or translation of cantilever
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When connecting the cable to the beam, a pinned joint will be used. This is to accommodate movement due to the live loads of people walking on the stairs. Figure 38: Pinned joint
Pinned joint needed to connect beam to cable to accommodate movement of people walking on stairs
Materials The stairs are made of stainless steel that has been galvanized to prevent rust.
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North Court Union House Figure 39: Location of North Court (The University of Melbourne, 2012)
Membranes are thin, flexible surfaces that carry loads through tensile stresses (Ching, 2008). The membrane structure in the North Court is stretched between various columns which receives these tensile loads and transfers them to the ground through compression. Figure 40: Membrane structure in North Court
Membrane structure in tension
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The membrane structure had a hole in the middle of it, where cables were connected to the structure around the central hole. These cables were then connected to the ground using pinned joints. When there are high wind loads, the cables undergo high tension forces. Figure 41: Cable structures connecting membrane structure to ground
Cables connecting membrane structure to ground. They undergo tension forces.
Figure 42: Cables undergoing tension
High wind loads acting on the membrane structure
This pushes membrane up, which causes cables to become very tense
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One of the main reasons why there was a hole in the middle was to allow water to escape during periods of rain in order to prevent accumulated rain loads on the membrane structure. The hole is directly above a drain, which the rainwater falls into, as seen in the diagram below. Figure 43: Rainwater escape
Slope of membrane allows water to flow towards hole
Movement of water towards drainage
Joints The main types of joints used in this structure are pinned joints, in order to allow movement of the membrane due to wind loads. Figure 44: Pinned joint
Pinned joints are used to connect the cables from the membrane to the ground to accommodate movement caused by wind loads
Materials Membranes are usually a woven textile or glass fibre coated fabric with a synthetic material such as silicone (Ching, 2008). Steel may have been used for the cables because of their good tensile properties. 48
Beaurepaire Centre Pool
Figure 45: Location of Bureaepaire Centre Pool (The University of Melbourne, 2012)
Structural Elements This structure was supported by flat columns that were placed at an angle to the beams above the glass. These columns were also connected to large beams that ran across the ceiling inside the building, and therefore carried the load of the roof structure. Figure 46: Inside Bureaupaire Centre Pool (Lovell Chen Architecture & Heritage Consultants, 2014)
Beans are placed along the pitched roof and transfer loads to the columns Columns then transfer loads of the roof structure to the ground
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Figure 47: Load path diagram
Beams transferring load from roof to columns that are outside building Glass Structural steel framing Columns transferring load to the ground
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Construction Systems The glazing found in the Bureaupaire centre pool is not a part of the structural system, but a part of the enclosure system. It is supported by vertical mullions and horizontal transoms. Without these elements, the large spans of glass will not be able to support themselves. Figure 48: Enclosure system
Columns
Glazing panels Stone to support loads of glass
Vertical mullions Horizontal transoms
As seen in the image below, the column has a pad footing below it, and the stone below the glass has a strip footing which indicates that the stone bears the load of the glazing. Figure 49: Footing systems
Strip footing to bear a continuous load of the stone
Pad footing to bear load of column
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These footing systems may have been chosen as the centre pool building does not have a significantly large amount of loads that need to be supported
Oval Pavilion Structural elements and construction systems The structural elements that can be observed are columns below the building which bear the loads of the building and transfer them to pad footings. The reason why these will be pad footings and not strip footings is because there are isolated point loads because of the columns as opposed to a continuous load, which is where strip footings are used. Figure 50: Foundations of building
The columns which support the building are seen in this image. Pad footings are used because the building is small and will have less loads.
Figure 51: Difference between pad footings and strip footings (Ching, 2008)
Strip footing supports continuous load – will be used in load bearing walls
Pad footing – similar to what is seen in the photograph because of column 52
Materials The wall at the back of the Pavilion (northern side) is constructed out of bricks. As seen in this image below, there are expansion joints in this wall to accommodate the expansion of bricks which occurs due to moisture absorption. Figure 52: Expansion joint
Expansion joint in brick wall to accommodate expansion of bricks – wall will start to crack if joint was absent
Weep holes needed to allow excess moisture to escape
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Old Geology South Lecture Theatre entrance Construction systems The lecture theatre entrance is circular with a circular slab on the top to enclose it. It comprises of the enclosure system which are the glass doors and the brick wall. The brick wall also bears the loads of the slab. Figure 53: Lecture theatre entry
Figure 54: Brick wall of lecture theatre entry
Glass panels with framing as support
Brick wall on the other side of the door
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Materials The materials used in this area are bricks for the load bearing wall and glass. Because the span of glass is relatively large in this section, it requires a structural frame for support. Bricks are used as they are good in compression and therefore are ideal in transferring vertical loads to the ground. They also contain weepholes to allow moisture to exit. Figure 55: Weep holes in brick wall
Weep holes needed to allow exit of excess moisture
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Frank Tate Pavilion The main structural elements that can be observed in this image are a beam and a diagonal column, which are load bearing and transfer the loads of the main structure to the ground. Figure 56: Frank Tate Pavilion (TimberDesignAwards, 2010)
Beam and column which support loads of the main structure
Figure 57: Load path diagram
Beam transferring load to column
Materials The materials used in this structure are timber and steel. The timber is used for aesthetic purposes, as indicated by its highly polished finish, and the steel is used for columns and beams due to its good compressive and tensile properties.
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Week 4 – Floor Systems and Horizontal Elements Knowledge Maps Structural Concepts Figure 58: Beams and Cantilevers (Newton, 2014)
Figure 59: Span and spacing (Newton, 2014)
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Construction systems Figure 60: Floor and framing systems (Newton, 2014) (Ching, 2008)
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Materials Figure 61: Concrete (Newton, 2014)
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Figure 62: Pre-cast and in-situ concrete (Newton, 2014)
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Case study in E Learnings Figure 63: The Pantheon (Hutson, 2014)
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Theatre session Figure 64: Oval Pavilion – Managers
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Studio Report Discussion on Scale Before beginning the questionnaire, we were divided into groups and told to discuss why and how scale was used in documenting building projects. Scales are used in order to fit structures into a paper, as it would be extremely difficult to draw a building in its actual dimensions. Larger scales will be used to represent plans, which show the building as a whole and do not show many details. An example is the ground floor plan of the Pavilion which is at a scale of 1:100. Smaller scales are used when details of specific sections are needed – this would include information such as structural joints and materials. Most of these details in the Pavilion drawing set are at a scale of 1:5. Construction Documentation Tour Questionnaire TITLE BLOCK List the types of information found in the title block on the floor plan page -
Consultants contact details e.g. structural and civil engineers, electrical engineers, landscape architects Client name Project name Drawing title Drawing number Compass Construction issue
Why might this information be important? Structural and civil engineers are critical for the construction of the building which is why the contact details are required. The drawing title as well as the drawing number is needed to categorize information. The drawing number also links to other sections of drawings. The construction issue indicates that this section of the building is ready for construction. DRAWING CONTENT – PLANS What type of information is shown in this floor plan? The floor plan shows an overview of the structure and includes general information such as where the different rooms are located, where the stairs are, where the windows and doors are placed in each room, what the different types of walls are and what materials are used in the different sections of the building.
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Provide an example of the dimensions as they appear on this floor plan. What units are used for the dimensions? Figure 65: Dimensions shown as distances between grids (Cox Architecture, 2014)
The distances between the grids are represented in millimetres.
Is there a grid? What system is used for identifying the grid lines? Yes, there is a grid. The horizontal lines are labelled alphabetically and the vertical lines are labelled numerically. The gridlines are also dashed. Figure 66: Grid in plan (Cox Architecture, 2014)
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What is the purpose of the legend? The legend symbolizes or abbreviates features of the ground floor plan. For example, ‘carpeted tiles’ are represented by the abbreviation ‘FL-01’, and it is this abbreviation that is shown in the plan. This ensures that the floor plan is neat and not cluttered with labels. Figure 67: Abbreviation used in plan (Cox Architecture, 2014)
Abbreviation for ‘carpeted tiles'
Why are some parts of the drawing annotated? Illustrate how the annotations are associated with the relevant part of the drawing. Annotations are used to indicate: Structures that already exist on the site and are supposed to remain there Figure 68: Structures that are not to be removed (Cox Architecture, 2014)
Features around the building that will be constructed newly 65
Figure 69: Newer features surrounding the Pavilion (Cox Architecture, 2014)
Illustrate how references to other drawings are shown on the plan. What do these symbols mean? Figure 70: References to other drawings (Cox Architecture, 2014)
The number at the bottom indicates the page where the drawing will be found and the number on top indicates the drawing number.
How are windows and doors identified? Provide an example of each. Is there a rationale to their numbering? What do these numbers mean? Can you find the answer somewhere in the drawings?
Windows and doors are identified through symbols that are shown below. Figure 71: Symbols for windows and doors (Cox Architecture, 2014)
Symbol for window
Symbol for door
The number at the top shows the window or door number of the particular room, and the bottom number shows the room that the window or door belongs too. These numbers also give a reference to the window or door schedule, which provides detailed information of how the windows or doors are to be constructed.
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The windows are labelled clockwise and doors are labelled anticlockwise. Figure 72: Labeling of windows and doors in plan (Cox Architecture, 2014)
Illustrate how floor levels are noted on the plan Figure 73: Representation of floor levels (Cox Architecture, 2014)
FFL stands for finished floor level which is shown in meters above datum
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Are some areas of the drawing clouded? Why? Yes. Some areas of the drawing have been clouded, which means that information has been revised or changed from a previous drawing. DRAWING CONTENT – ELEVATIONS What type of information is shown in this elevation? How does it differ from the information shown on the plan? The elevation shows the height of the building, as well as the types of materials and finishes. The plan shows the general information of the Pavilion from an aerial view whereas the elevations show specific information of the outside of the building in different areas of the Pavilion. Are dimensions shown? If so, how do they differ from the dimensions shown on the plan? Provide an example of the dimensions as they relate to the elevation. Yes, dimensions are shown, which indicates the height of the parapet. This differs from the dimensions shown on the plan which showed the distances between the grids. Figure 74: Parapet dimension in South Elevation (Cox Architecture, 2014)
What types of levels are shown on the elevations? Illustrate how levels are shown in relation to the elevation. The levels shown are the finished floor level in meters above datum and the spot level – reduced level in meters above datum, which are indicated in relation to the existing pavilion, the ground floor and the function parapet.
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Figure 75: Levels in South Elevation (Cox Architecture, 2014)
Is there a grid? If so, how/where is it shown? The grid in the elevations is in the form of vertical lines only, as it is in relation to the floor plan drawings. Figure 76: Grids in South Elevation (Cox Architecture, 2014)
What types of information on the elevations are expressed using words? Illustrate how this is done. Specific details of features of the building are illustrated using words, such as the existing structures that are to remain, information about new elements that are added to the existing building.
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Figure 77: Existing structures to remain in South Elevation (Cox Architecture, 2014)
Figure 78: New structures in South Elevation (Cox Architecture, 2014)
NEW TIMBER COLUMNS AND STRUCTURE TO EXISTING VERANDAH
NEW DOUBLE GLAZED DOORS TO MATCH EXISTING
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Illustrate how doors and windows are identified on the elevations Doors and windows are labelled with the same symbol shown in the plan. Doors are labelled from left to right and windows are labelled from right to left. Figure 79: Windows in South Elevation (Cox Architecture, 2014)
Windows labeled from right to left
Figure 80: Doors in South Elevation (Cox Architecture, 2014)
Doors labeled from right to left
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Find where this elevation is located on the plans The elevations are located at the points shown below, where A is the South Elevation, B is the North Elevation, C is the East Elevation and D is the West Elevation. Figure 81: Location of elevations (Cox Architecture, 2014)
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DRAWING CONTENT – SECTIONS What type of information is shown in this section? How does it differ from the information shown in the plan and elevation? The sections show details of the foundation system of areas in the building as well as the cross section of different rooms in the building, which the plans and the elevations do not show. Illustrate how the section drawing differentiates between building elements that are cut through and those that are shown in elevation. The elements that are cut through have been backlined and the elements that are shown in elevation are shown in thin lines. Figure 82: Elements that are cut through and elements that are in elevation in Section 1 (Cox Architecture, 2014)
This element has been drawn with thicker lines, indicating that it has been cut through
This element has been drawn in thin lines, indicating that it is in elevation
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Provide examples of how different materials are shown on the sections. The materials in the sections are not annotated, but are shown with enough detail to be identified. Figure 83: Materials in the sections (Cox Architecture, 2014)
Brick walls, indicated by the blocks laid with a stretcher course
Foundation made with concrete
Find where this section is located on the plan
Sections are represented on the ground floor plan with the symbols shown in this diagram. The number on top indicates the section number and the number at the bottom indicates the drawing number where these sections are found
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DRAWING CONTENT – DETAILS What sorts of things are detailed? The walls, internal elements and finishes, the building, the canopy, the plan, the joineries, the stairs and the external seating are detailed. Are the details compressed using break lines? Why? Yes. The details are drawn at a much larger scale, so certain features need to be shortened in order to fit into the page. Provide examples of how different materials are shown on drawings at this scale. At this scale, the drawings provided more detailed descriptions of the materials in different areas of the pavilion. Most materials were labelled with a reference that could be checked in the Technical Reference Sheet that could be found at the back of the drawing set. The examples shown below are from the Link Detail on drawing 46-01 from Cox Architecture (2014). Figure 84: Material in Link Detail
TIM-10: Internal timber batten screen
Figure 85: Material in Link Detail
CLG-06: Timber ceiling lining
Figure 86: Material in the Link Detail
Figure 87: Material in the Link Detail
INS-09: Thermal insulation
RFS-01: Metal deck roof
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Find the locations of these details on the plans, elevations and sections. Figure 88: Canopy detail section on ground floor plans (Cox Architecture, 2014)
Figure 89: Canopy detail section on North Elevation (Cox Architecture, 2014)
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Figure 90: North Function Wall Detail in Section (Cox Architecture, 2014)
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Answers to Part 3
How does the information in your drawing compare to what you saw on site last week? We were not able to observe the Oval Pavilion within a close range last week. The photos were also taken behind a fence, which impairs the view of the Pavilion under construction. Figure 91: Pavilion under construction
Similar in terms of appearance to drawing, but does not provide information about materials or height – materials cannot be identified at distance we were at
I was able to locate this area of the building in the drawing set, which was the West Elevation of the Pavilion. In terms of differences, the information in the drawing set gave the height of the section observed as well as the materials used to build this part of the building, which could not be identified by merely observing the building. Figure 92: Structure with information from drawing set (Cox Architecture, 2014)
Repair existing roof turret
Galvanized roof sheet Gutters to existing roof External timber lining
External timber lining
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How does the scale of the building compare to the scale of the drawings? As stated before, the drawings have to be scaled down as the actual dimensions of the building cannot be represented in a drawing. The second part of the building viewed was the North Elevation, which can be seen entirely in the scaled 1:100 drawing. On site, it was just the brick wall that could be seen. Figure 93: Brick wall of North Elevation
Due to larger scale of brick wall, more details such as an expansion joint and weep holes can be seen, which the drawing does not show
Figure 94: Drawing of part of North Elevation (Cox Architecture, 2014)
Features seen in actual building cannot be seen in drawing of elevation due to difference in scale
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How do architectural and structural drawings differ? Architectural drawings show details in terms of aesthetics and structural drawings show how individual elements are linked together. This is illustrated using the canopy as an example. Figure 95: Architectural drawing of canopy (Cox Architecture, 2014)
Indicates finishes on the structural steel Information about materials is provided
Figure 96: Structural drawing (Wood & Grieve Engineers )
Shows exactly how all the members in the truss beams are linked together – no information about materials or finishes
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Week 5 – Columns, Grids and Wall Systems Knowledge Maps Structural Concepts Figure 97: Columns (Newton, 2014)
Figure 98: Frames (Ching, 2008)
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Construction Systems Figure 99: Walls, Grids and Columns (Ching, 2008) (Newton, 2014)
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Materials Figure 100: From wood to timber (Newton, 2014)
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Figure 101: Engineered Timber Products (Newton, 2014)
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Figure 102: Properties of timber (Newton, 2014)
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Case Study in E Learnings Figure 103: Gehry's Own Home (Lewi, 2014)
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Theatre Session
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Studio Report In this studio session, we were divided into groups and had to build a 1:20 model of a section of the Oval Pavilion. Actual structure The structure was the canopy located in the south of the Pavilion. It comprises of truss beams and columns, which support the metal roof sheeting that is placed on top of it. Figure 104: Canopy structural system (Wood & Grieve Engineers )
Truss beam which bears load of roof structure Columns transfer the loads from the truss beam to the ground
Identifying structural elements As seen in the diagram above, the main structural elements are a truss beam and columns. The truss beams bear the load of the metal roof structure that is laid on top and transfers these to the columns. The columns then transfer the loads to the ground. A truss beam was used as it will provide multiple load paths. Figure 105: Load path diagram (Wood & Grieve Engineers )
Column transfers load from a wide area to a smaller point
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Materials The truss system is constructed with steel and has external timber panels and plywood cladding. Steel was used for the main structural system as it is good in both compression and tension, which is needed in a beam. It is also used for columns because it is good in compression. Figure 106: Part of canopy detail section (Cox Architecture, 2014)
Structural joint 1
Metal roof sheeting
External timber panels External plywood cladding Figure 107: Part of canopy detail section (Cox Architecture, 2014)
Metal roof sheeting
Steel structural system Structural joint 2
Structural joint 3 External plywood cladding
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Figure 108: Part of canopy detail section (Cox Architecture, 2014)
Metal roof Structural decking joint 4
External plywood cladding
Structural joints The joints that were used to connect the members to each other and to the ground were all fixed joints, which were needed to prevent rotation and translation of the structural members, which would have resulted in lateral instability. Figure 109: Structural joint 1 (Cox Architecture, 2014)
Metal roof decking
End cap to match metal roof decking
Steel angle to edge of cladding External timber panel 90
(Cox Architecture, 2014)
Figure 110: Structural joint 2 (Cox Architecture, 2014)
Brass ceiling trim to mitre joint
External plywood cladding
Figure 111: Structural joint 3 (Cox Architecture, 2014)
External timber panel
Steel base angle fixed to concrete slab, paint to expose structural steel
Figure 112: Structural joint 4 (Cox Architecture, 2014)
Brass ceiling trim to mitre joint
External timber panel
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Materials used in model As our section comprised of trusses, and columns, we decided to use 1.5mm sheets of balsa wood cut into strips that were 2.5mm in width as they would facilitate the process of making these structures. Process We started by assembling the individual trusses first, which were found on the structural drawing number S04.01. As the drawings were on a scale of 1:100 on A1 paper, they were multiplied by 10 in order to get dimensions that would be at a scale of 1:20. Figure 113: Truss CT2
Balsa wood members have been connected using UHU glue to form fixed joints that do not undergo rotation or translation
Figure 114: Truss CT6
Signs of failure can be observed – members started to snap as they were too thin, and had to be fixed
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Figure 115: Truss CT5
Column at the end of the truss was too thin – had to be removed later
The individual trusses were then put together as shown in the structural drawing S03.02 which indicated how they were all supposed to be put together. They were joined together with UHU glue, which formed fixed joints. Figure 116: Joining truss CT8 and CT9
Truss CT8 Beam that connects the two trusses Truss CT9
Column which transfers loads to the ground
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Figure 117: Part of roof structure
Roof structure with most of the trusses
Figure 118: Completed roof structure
Member sizes of columns were very thin, made it difficult for structure to stand without support
Although we managed to finish the roof structure, we were unable to turn it over as the structure could not stand without support, as the thin members were not strong enough to bear the load of the entire structure. They represented long columns which buckled due to a compression force that was too large compared to their cross section.
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Comparison with other models Figure 119: Model of another roof system
Fixed joints between members with masking tape
Thicker members compared to our model
The other roof system constructed was more stable than our model due to the thicker columns, which meant that they were able to bear the load of the truss beam. Therefore, the whole structural system was able to stand without support. The members were also fixed together with masking tape whereas ours were fixed with glue. Figure 120: Model of enclosure system
Box board and rigifoam used to form enclosure system
The main structural elements in this model are columns, panels and slabs as this forms an enclosure system. As there were no thin members in this system, materials like rigifoam and box board were used, and materials like balsa wood strips were not needed.
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Week 6 – Spanning and Enclosing Space Knowledge Maps Structural concepts
Figure 121: Trusses (Ching, 2008)
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Figure 122: Plates and grids (Ching, 2008)
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Construction systems Figure 123: Roof types (Newton, 2014) (Ching, 2008)
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Figure 124: Types of roofs (materials) (Ching, 2008) (Newton, 2014)
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Materials Figure 125: Introduction to metals (Newton, 2014)
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Figure 126: Properties of metals (Newton, 2014)
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Figure 127: Ferrous metals (Newton, 2014)
Figure 128: Uses of non-ferrous metals (Newton, W06_m3 Non ferrous Metals, 2014)
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Case study in E Learnings Figure 129: Spanning Spaces (Lewis, 2014)
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Theatre Session
Figure 130: Concepts of successful development
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Studio Report Knowledge Maps of Site Visit Presentations Figure 131: Yarraville Site
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Figure 132: North Melbourne Site
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Week 7 – Detailing Strategies 1 Knowledge maps Structural concepts
Figure 133: Arches, Domes and Shells (Ching, 2008)
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Construction systems
Figure 134: Detailing for moisture (Newton, 2014)(Ching, 2008)
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Figure 135: Detailing for heat (Ching, 2008) (Newton, 2014)
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Materials Figure 136: Rubber (Newton, 2014)
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Figure 137: Properties of rubber (Newton, 2014)
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Figure 138: Plastics (Newton, 2014)
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Figure 139: Properties of plastic (Newton, 2014)
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Figure 140: Paints (Newton, 2014)
Figure 141: Properties of paint (Newton, 2014)
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Week 8 - Openings Knowledge Maps Structural concepts Figure 142: Geometry and moment of inertia (Ching, 2008)
Figure 143: Deformation (Ching, 2008)
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Construction Systems Figure 144: Door elements (Ching, 2008)
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Figure 145: Door types (Ching, 2008)
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Figure 146: Door types (materials) (Newton, 2014)
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Figure 147: Window elements (Ching, 2008)
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Figure 148: Window types (Ching, 2008)
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Figure 149: Window types (materials) (Ching, 2008)
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Figure 150: Glazed curtain walls (Ching, 2008)
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Materials
Figure 151: Glass components (Newton, 2014)
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Figure 152: Properties of glass (Newton, 2014)
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Figure 153: Glass types and manufacturing (Newton, 2014)
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Figure 154: Other types of glass and products (Newton, 2014)
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Case Study from E Learnings Figure 155: Glass skins (Sadar, 2014)
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Studio Report The class was given various areas of the Oval Pavilion to draw at a 1:1 scale on A1 paper. I was assigned drawing 7 which was a section of a service area in the faรงade details of the Oval Pavilion. As it is located in close proximity to the wet area, it functions as a drainage system allowing the exit of moisture through a cavity flashing. The water then leaves through the weep hole in the brick face. As this was a section of the building, it could not be completely observed from the outside of the Pavilion. The only visible element of the drawing was the brick face, shown in figure 156, which is why many photos were not taken. Figure 156: Brick face of section
Face brickwork
Weep holes Gap between brick wall and ground where structural steel angle is
Figure 157: Section of service area
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This service section is located in the North Function wall. The location of the wet area in relation to the service section can be seen in Figure 158 and 159. Figure 158: Part of the north Function Wall (Cox Architecture, 2014)
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Figure 159: Service section represented in the north function wall on section 2 of Pavilion (Cox Architecture, 2014)
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An annotated copy of the diagram is shown in Figure 160. Figure 160: Annotated diagram of section
Face brickwork
Vapour barrier
Weep holes as required
Cavity flashing
Paint to expose structural steel to shelf angle
Face blockwork (concrete)
As this section is located within close proximity to a wet area, the vapour barrier, or the vapour diffusion retarder was introduced to regulate moisture flow at the molecular level. This moisture control function happens wherever the VDR is used in the structure. Unlike an air infiltration barrier, the VDR does not have to be continuous, sealed, or free of holes; a perforation in a VDR simply allows more vapor diffusion in that area compared with other areas where vapor diffusion is less restrictive (EcoBuilding Pulse, 2009), which explains why the barrier is indicated using dashed lines.
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Week 9 – Detailing Strategies 2 Knowledge Maps Structural concepts Figure 161: Stress and Structural Members (Ching, 2008)
Figure 162: Structural joints (Ching, 2008)
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Figure 163: Movement joints (Ching, 2008)
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Construction systems Figure 164: Construction detailing (Newton, 2014) (Ching, 2008)
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Materials Figure 165: Comparing monolithic and composite materials (Newton, 2014)
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Figure 166: Composite materials (Newton, 2014)
Figure 167: Fibre Glass (Newton, 2014)
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Figure 168: Aluminium sheet composites (Newton, 2014)
Figure 169: Timber composites (Newton, 2014)
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Figure 170: Fibre reinforced polymers (Newton, 2014)
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Figure 171: Finish work
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Studio Report The site visited was the Watersun site at the corner of Queensbury Street and Dryburgh Street in North Melbourne. The site consisted of apartments and townhouses which were situated in various areas of the building. Location 1 – Basement The basement of the building was to be used as a car park. The whole area was constructed using concrete, as it is a load bearing material, and is needed to withstand the loads of the building along with the loads of the cars that will be parked there. Retaining walls As these walls need to withstand ground pressure which acts upon it, they were made of concrete blocks that were corefilled and reinforced with steel. As concrete is strong in compression but weak in tension, adding steel in the form of a mesh or bars, which is strong in tension, will improve the structural performance of concrete (Newton, 2014). This forms a composite material. Figure 172: Concrete retaining wall
Concrete retaining wall – core filled blockwork with steel reinforcement
As this section of the building is underground, waterproofing is required to prevent efflorescence taking place, which will deteriorate the aesthetic quality and structural performance of the concrete. All external walls are therefore waterproofed using corrugated drip systems.
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Columns Concrete columns were used in the basement to support the loads from the rest of the building. These columns were cast in situ, where the formwork and reinforcement was first assembled and the concrete was poured from the top. Concrete was chosen as a material for columns because it is good in compression. Reinforcement was added to improve the structural performance of concrete, in the same manner as the blockwork. Figure 173: Concrete columns
Figure 174: Column formwork
Concrete is poured from the top
In situ load bearing concrete columns
Reinforcement – steel bars which project from the ground
Yokes – clamping devices for keeping column forms and the tops of wall forms from spreading under the fluid pressure of concrete
Once the concrete is poured, it is then vibrated (generally using poker vibrators) to remove air bubbles. The formwork may usually be removed the day after the concrete is cast, taking care not to damage the surface and corners of the concrete (The Concrete Society, n.d.)
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Figure 175: Load path diagram of concrete columns
Loads from the building are transferred to the foundations through concrete columns
Ceiling The concrete ceiling was also cast on site, where concrete was poured into formwork sheets, which are indicated by the lines on the ceiling shown below. As the electrical work was done in the formwork, it needs to be completed before the concrete is poured. Figure 176: In situ concrete ceiling
In situ concrete ceiling, where lines indicate placement of formwork
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Service systems The service systems that are found in the basement are pipes for stormwater drainage, gas and fire service systems. Sprinklers are included in this category. Suspended cable trays are included to support cables. Figure 177: Cable trays
Suspended cable tray used to support cables
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Location 2 – Roof Roof details The second location in the building was the roof, which was a flat roof made out of reinforced concrete. As it is a flat roof, it requires a continuous membrane roofing material, which was done through two layers of waterproof coating and a layer of screed. The roof also consisted of an upturned edge beam to form a parapet wall. Figure 178: Concrete roof with parapet wall
Parapet wall formed by upturned edge beam
The roof is also made from in situ concrete, where the formwork has been laid in place and the concrete is poured using a bubble crane. The bubble crane also assembled the precast concrete panels that formed the exterior walls of the building. The panels were precast because casting panels in situ will be difficult and time consuming. As the panels below the concrete slab that forms the roof are load bearing, as will be discussed later, they will be connected to the roof as shown below. Figure 179: Connection between slab and bearing panel (Ching, 2008)
Steel dowel to connect slab to panel
Parapet wall
High density plastic bearing strip
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Connection is a fixed joint – maintains angular relationship between joined elements and restricts rotation and translation (Ching, 2008), which is what is needed when connecting a slab and a panel.
Lightwells In order to allow natural light into the building, lightwells are constructed on the roof, where the light is used reaches the apartments and townhouses. This method is beneficial as it reduces the need for electrical lighting. Figure 180: Lightwells
Figure 181: Section of lightwell through the building
Apartments
Apartments
Exterior concrete panels
Townhouses
Townhouses
Section of one lightwell through building – provides natural light for all floors
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Water escape from the roof In order to allow water to leave the roof, a downpipe was fitted in the slit shown in the parapet wall below and sealed in place with concrete. Therefore, the roof will be slightly sloped in order to facilitate the movement of water towards this pipe. Figure 182: Section showing downpipe
Downpipe which has been sealed in place with concrete
Roof slab will be at a slight angle to allow movement of water towards the downpipe
Figure 183: Section showing flow of water to downpipe
Downpipe which carries water away from roof – prevents penetration into building
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Considerations (control joints) The parapet wall in the roof also had small slits in them, which may be possible areas for control joints to accommodate the shrinking of concrete. These slits may be fitted with corking and a backrod which will compress due to shrinkage. Figure 184: Grooves in parapet wall
Grooves in parapet wall for control joints
Figure 185: Control joint (Ching, 2008)
Figure 186: Control joint once expanded (Ching,2008)
Control joint expands due to shrinking of concrete
Control joint as installed
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Location 3 – Apartment section Walls The walls in the apartment areas consist of a metal studwork framing system that comprises of lightweight steel columns. They are used in both exterior loadbearing curtain walls and in nonloadbearing partition walls within the building (Ching, 2008). The exterior walls transfer the loads of the roof to the foundations and the steel frame The steel studs are made from lightweight channel studs. Figure 187: Channel studs (Ching, 2008)
Light gauge steel studs are prepunched to allow piping, wiring and bracing to pass through
Figure 103: Metal studwork
Metal studwork in external load bearing wall – needed as a frame for the plaster
Metal studwork in a partition wall – to be plastered
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Precast concrete panels and in-situ ceiling As mentioned before, the panels which formed the exterior walls were pre-cast and lifted into place using a bubble crane. In Figure 105, the individual panels can be seen in the apartment section. These panels will be load bearing, and may have metal studwork assembled later to facilitate plastering. Figure 188: Precast concrete panels
Individual concrete panels
As mentioned before, the roof was formed from in-situ concrete which was poured using a bubble crane. The evidence of formwork can be seen in the image below. Figure 189: Formwork for in-situ roof/ceiling
Formwork for the ceiling made evident through the lines visible in the concrete slab
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Connections Figure 190: Connections between steel members (Ching, 2008)
Steel members (channel studs)
The steel columns are connected to the foundation with an angle clip which welded to the stud and then bolted to the foundation Figure 191: Connection between member and wall
In this image, the metal clip appears to have been bolted into the concrete wall and then connected to the steel column
In both instances, they will be fixed joints as rotation and translation of the two elements will need to be restricted in order to ensure structural stability.
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Location 4 – Townhouse section There are two townhouse levels that are connected by a set of stairs for which the formwork is shown below. This was constructed using timber. Figure 192: Timber formwork for stairs
Timber formwork for stairs leading to upper level townhouse
As seen with the apartments, the concrete walls are loadbearing with a metal stud frame which will then be plastered over.
Figure 193: Metal stud framing in apartment
Metal stud framing. As with the stud framing before, there are holes within the columns for services
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Week 10 – When things go wrong Knowledge Maps Structural concepts Figure 194: Lateral supports (Newton, 2014)
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Figure 195: Dynamic loads (Ching, 2008)
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Construction systems Figure 196: Collapses and failures (Ashford, 2014)
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Materials Figure 197: Heroes and Culprits (Hes, 2014)
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Figure 198: Building Materials (Ching, 2008)
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Figure 199: Building Materials (Ching, 2008)
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Figure 200: The Statue of Liberty - A tale of corrosion (Cameron, 2014)
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Studio Report For this studio session, we went to the Oval Pavilion and examined our detail and used it to form the 3D drawings of the detail, which linked the 2D drawing with what was seen on site. The only elements that were visible were the brick face, the weep holes and the structural steel. Figure 201: Section on site
Brick face visible Gap between brick and ground as indicated in the section drawing. Structural steel visible inside the gap.
Figure 202: Close-up of detail
Weep holes to allow moisture to leave
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Detailing decisions and purpose The service area is in close proximity to a wet area, so the detailing decisions reflect the waterproofing needed. There is a gap between the concrete wall and the visible brick face within which there is a cavity flashing, which is put there to allow water from the wet area to leave through gravity through the weephole. Figure 203: Detailing decisions (Cox Architecture, 2014)
According to the detail drawings, the steel angle is connected to the flashing. The steel has been painted instead of galvanized, which may have been done to save costs. The vapour barrier has been placed on top of the concrete to control the entry of moisture into the structure.
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Waterproofing elements The main waterproofing elements in this section are a vapour barrier, a cavity flashing and weep holes. As mentioned in the studio report of Week 8, the vapour barrier is used to prevent the entry of moisture, the cavity flashing removes moisture through gravity, which exits through the weep holes. Why and where things go wrong As the structure is located in a wet area, the brick will absorb a lot of moisture. Due to this, the steel below the cavity flashing has begun to show signs of corrosion as it is extremely close to the moisture containing bricks. The steel will also absorb moisture from the surrounding soil Figure 204: Corrosion in structural steel
Steel showing signs of corrosion
Economic implications If the steel continues to corrode, it will have to be replaced which will be an expensive task. If steel is to be placed next to bricks or in contact with the ground, it needs to be galvanized to prevent corrosion. Other ways of preventing the steel from corroding is to have it at a higher height above the ground so that it is in less contact with moisture.
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Glossary of Terms Week 1 Beam – rigid structural members designed to carry and transfer transverse loads across space to supporting elements. The noncurrent pattern of forces subjects a beam to compression and tension, which must be resisted by the internal strength of the material (Ching, 2008) Compression forces – an external load pushing on a structural member, resulting on the shortening of the material (Newton, 2014) Load path – the route a load takes through a structural system to reach the ground (Ching, 2008) Masonry – building with units of various natural or manufactured products, usually with the use of mortar as a bonding agent (Ching, 2008) Point load– A concentrated load in a specific position on a structural member (WebFinance Inc, 2014) Reaction force – equal and opposite forces that resist an applied force (Ching, 2008) Week 2 Brace - A diagonal tie that interconnects scaffold members (WebFinance Inc, 2014) Columns – rigid, relatively slender structural members designed primarily to support axial compressive loads applied to the ends of the members (Ching, 2008) Frame – an assembly of vertical and horizontal structural members (WebFinance Inc, 2014) Stability – the measure of the ability of a structure to withstand overturning, sliding, buckling or collapsing (WebFinance Inc, 2014) Structural joints – connectors used to joint structural elements (Ching, 2008) Tension - external load pulling on a structural member, causing the material to elongate (Newton, 2014)
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Week 3 Moment - tendency of a force to produce rotation of a body about a point or line, equal in magnitude to the product of the force and the moment arm and acting in a clockwise or anticlockwise direction (Ching, 2008) Figure 205: Moment (Ching, 2008)
Retaining wall – structure used to sustain the pressure of the earth behind it (WebFinance Inc, 2014) Figure 206: Retaining wall (Ching, 2008)
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Pad footings – individual spread footings supporting freestanding columns and piers (Ching, 2008) Figure 207: Pad footing (Ching, 2008)
Slab on ground – a concrete slab supported directly by the earth and thickened to carry wall and column loads from an economical foundation and floor system (Ching, 2008) Figure 208: Slab on ground (Ching, 2008)
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Strip footings – continuous spread footings of foundation walls (Ching, 2008) Figure 209: Strip footing (Ching, 2008)
Substructure – lowest division of the building constructed partially or wholly below the ground. Primary function is to support and anchor the superstructure above and transmit its loads to the earth. (Ching, 2008) Figure 210: Substructure (Ching, 2008)
Week 4 Concrete plank - A hollow-core or solid, flat beam used for floor or roof decking. Concrete planks are usually precast and pre-stressed (WebFinance Inc, 2014)
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Girder - A large principal beam of steel, reinforced concrete, timber, or a combination of these, used to support other structural members at isolated points along its length (WebFinance Inc, 2014). Figure 211: Girder (Ching, 2008)
Joist - Parallel beams of timber concrete, or steel used to support floor and ceiling systems (WebFinance Inc, 2014) Figure 212: Joist (WebFinance Inc, 2014)
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Spacing – repeating distance between a series of like or similar elements (Newton, 2014) Figure 213: Spacing (Newton, 2014)
Span – distance measured between two structural supports (Newton, 2014) Figure 214: Span (Newton, 2014)
Steel decking – corrugated to increase its stiffness and spanning capability. Decking serves as a working platform during construction and as formwork for an in situ concrete slab (WebFinance Inc, 2014). Figure 215: Steel decking (WebFinance Inc, 2014)
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Week 5 Axial load - The longitudinal force acting on a structural member (WebFinance Inc, 2014). Figure 216: Axial load (Ching, 2008)
Buckling – the sudden lateral or torsional inability of a slender structural member induced by the action of an axial load before the yield stress of the material is reached Figure 217: Buckling (Ching, 2008)
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Lintel - A horizontal supporting member, installed above an opening such as a window or a door, that serves to support the load of the wall above it (WebFinance Inc, 2014). Figure 218: Lintel (WebFinance Inc, 2014)
Noggings – Members placed in rows holding together the long thin members in stud framing together in order to prevent them from buckling (Newton, 2014) Figure 219: Noggings (Ching, 2008)
Seasoned timber - Timber that is not green, having a moisture content of 19% or less, and is airor kiln-dried.
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Stud - A framing member, designed to be used in framing walls. Studs are most often 2" x 4", but 2" x 3", 2" x 6" and other sizes are also included in the stud category. Studs may be of timber, steel, or composite material (WebFinance Inc, 2014). Figure 220: Stud (Ching, 2008)
Week 6 Alloy – a mixture of two or more metals (Newton, 2014) Cantilever – created when a structural member is supported only at one end. The function of a cantilever is to carry loads along the length of a member and transfer these loads to the support (Newton, 2014) Figure 221: Cantilever (Ching, 2008)
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Eave - the portions of a roof that project beyond the exterior walls of a building (WebFinance Inc, 2014) Figure 222: Eave (WebFinance Inc, 2014)
Portal frame – a series of braced rigid frames with purlins for the roof and girts for the walls. The walls are usually finished with sheet metal (Newton, 2014) Figure 223: Portal frame (Ching, 2008)
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Purlin - One of several horizontal structural members that support roof loads and transfer them to roof beams Figure 224: Purlin (WebFinance Inc, 2014)
Rafter – a series of sloping parallel beams used to support a roof covering (WebFinance Inc, 2014) Figure 225: Rafter (WebFinance Inc, 2014)
Soffit - The underside of a part or member of a structure, such as a beam, stairway, or arch. (WebFinance Inc, 2014) Figure 226: Soffit (WebFinance Inc, 2014)
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Top chord – the upper section of a truss (WebFinance Inc, 2014) Figure 227: Top chord (Ching, 2008)
Week 7 Drip - A groove in the underside of a projection, such as a windowsill, that prevents water from running back into the building wall (WebFinance Inc, 2014). Figure 228: Drip (Ching, 2008)
Down pipe – pipe that takes excess water from a roof to a storm water sewer (Ching, 2008)
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Flashing – thin continuous piece of material installed to prevent passage of water into a structure from an angle or joint. The upturned edges and sloping surfaces use gravity to lead water to the outside Figure 229: Flashing (WebFinance Inc, 2014)
Gutter - A shallow channel positioned just below and following along the eaves of a building for the purpose of collecting and diverting water from a roof (WebFinance Inc, 2014). Figure 230: Gutter (WebFinance Inc, 2014)
Insulation - material used to reduce the effects of heat, cold, or sound (WebFinance Inc, 2014) Parapet – the part of a wall that extends above roof level (WebFinance Inc, 2014). Figure 231: Parapet (Ching, 2008)
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Sealant - an impervious substance used to fill joints or cracks in concrete or mortar, or to exclude water and solid matter from any joints (WebFinance Inc, 2014). Figure 232: Sealant (Ching, 2008)
Vapour barrier - material used to prevent the passage of vapor or moisture into a structure or another material, thus preventing condensation within them (WebFinance Inc, 2014) Figure 233: Vapour barrier (WebFinance Inc, 2014)
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Week 8 Deflection – the perpendicular distance a spanning member deviates from a true course under transverse loading, increasing with load and span, and decreasing with an increase in the moment of inertia of the section or the elasticity of the material (Ching, 2008) Figure 234: Deflection (Ching, 2008)
Door Furniture – the parts of the door including the rough opening, head, jamb, stop, door hardware and architrave (Ching, 2008) Moment of inertia – the sum of the products of each element of an area and the square of its distance from a coplanar axis of rotation. It is a geometric property that indicates how the cross sectional area of a structural member is distributed and does not reflect the intrinsic physical properties of a material (Ching, 2008) Shear force - The algebraic sum of all the tangential forces acting on either side of the section at a particular location in a flexural member (WebFinance Inc, 2014) Figure 235: Shear force (Ching, 2008)
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Stress - Intensity of internal force exerted by either of two adjacent parts of a body on the other across an imagined plane of separation. When the forces are parallel to the plane, the stress is called shear stress; when the forces are normal to the plane, the stress is called normal stress; when the normal stress is directed toward the part on which it acts it is called compressive stress; when it is directed away from the part on which it acts it is called tensile stress (WebFinance Inc, 2014) Figure 236: Stress (Ching, 2008)
Window sash – the fixed or movable framework of a window in which panes of glass are set. Its section profile varies with material, manufacturer and type of operation (Ching, 2008). Figure 237: Window sash (WebFinance Inc, 2014)
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Week 9 Composite beam - A beam combining different materials to work as a single unit, such as structural steel and concrete or cast-in-place and precast concrete (WebFinance Inc, 2014) Figure 238: Composite beam (WebFinance Inc, 2014)
Cornice - An ornamental molding of wood or plaster that encircles a room just below the ceiling (WebFinance Inc, 2014) Figure 239: Cornice (WebFinance Inc, 2014)
Sandwich panel - A panel formed by bonding two thin facings to a thick, and usually lightweight, core. Typical facing materials include plywood, single veneers, hardboard, plastics, laminates, and various metals, such as aluminum or stainless steel. Typical core materials include plastic foam sheets, rubber, and formed honeycombs of paper, metal, or cloth (WebFinance Inc, 2014)
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Skirting – A corner block where a base and vertical framing meet (WebFinance Inc, 2014) Figure 240: Skirting
Week 10 Braced Frame - a wooden structural framing system in which all vertical members, except for corner posts, extend for one floor only. The corner posts are braced to the sill and plates (WebFinance Inc, 2014) Figure 241: Braced Frame (Ching, 2008)
Corrosion - The oxidation of a metal or other material by exposure to chemical or electrochemical action such as rust (WebFinance Inc, 2014) Defect - Any condition or characteristic that detracts from the appearance, strength, or durability of an object (WebFinance Inc, 2014)
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Fascia - A board used on the outside vertical face of a cornice (WebFinance Inc, 2014) Figure 242: Fascia (WebFinance Inc, 2014)
IEQ - An important criterion for green, or sustainable, building design, this refers to general overall building occupant comfort. Includes humidity, ventilation and air circulation, acoustics, and lighting (WebFinance Inc, 2014) Lifecycle - A term often used to describe the period of time that a building or material can be expected to actively and adequately serve its intended function (WebFinance Inc, 2014) Shear wall - A wall portion of a structural frame intended to resist lateral forces, such as earthquake, wind, and blast, acting in the plane or parallel to the plane of the wall (WebFinance Inc, 2014) Figure 243: Shear wall (Ching, 2008)
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Soft storey – has lateral stiffness or strength significantly less than the stories above. Deflects considerably under seismic loads and will collapse while other floors remain intact, which leads to the collapse of the whole building. Figure 244: Soft storey (Ching, 2008)
Soft storey
.
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Reference List Ashford, P. (2014). W10_c1 When things go wrong. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=yNElfYRi_I&feature=youtu.be Cameron, R. (2014). W10_m2 A Tale of Corrosion. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=2IqhvAeDjlg&feature=youtu.be Cement Sustainability Initiative. (2012). Sustainability Benefits of Concrete. Retrieved from World Business Council for Sustainable Development : http://www.wbcsdcement.org/index.php/about-cement/benefits-of-concrete Ching, F. D. (2008). Building Construction Illustrated (4th ed.). Hoboken, New Jersey : John Wiley & Sons. Cox Architecture. (2014). Oval Pavilion Construction Drawings. Design. City. Living. (2012). Lot 6 Cafe and Bar - Melbourne University. Retrieved from http://www.designcityliving.com/2012/05/lot-6-cafe-and-bar-melbourne-university.html EcoBuilding Pulse. (2009). Understanding Vapour Barriers. Retrieved from http://www.ecobuildingpulse.com/building-science/understanding-vapor-barriers.aspx Hes, D. D. (2014). W10_m1 Heroes and Culprits. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=yNElfYRi_I&feature=youtu.be Hutson, A. (2014). The Pantheon. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=9aL6EJaLXFY&feature=youtu.be Lewi, D. H. (2014). Gehry's Own Home. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=iqn2bYoO8j4&feature=youtu.be Lewis, D. M. (2014). Spanning Spaces. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=Zx4tMuSaO8&feature=youtu.be Lovell Chen Architecture & Heritage Consultants. (2011). Underground Carpark and South Lawn Conservation Management Plan. Retrieved from http://www.pcs.unimelb.edu.au/standards_and_policies/docs/master_plans/Underground_ Car_Park_and_South_Lawn_CMP.pdf
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Lovell Chen Architecture & Heritage Consultants. (2014). Beaurepaire Centre. Retrieved from http://www.lovellchen.com.au/beaurepaire.aspx Newton, C. (2014). Beams and Cantilevers. Retrieved from Learning Management System Constructing Environments: https://app.lms.unimelb.edu.au/bbcswebdav/courses/ENVS10003_2014_SM1/WEEK%2 004/BEAMS%20AND%20CANTILEVERS.pdf Newton, C. (2014). Geometry and Equilibrium. Retrieved from Learning Management System Construction Environments: https://app.lms.unimelb.edu.au/bbcswebdav/courses/ENVS10003_2014_SM1/WEEK%2 003/GEOMETRY%20AND%20EQUILIBRIUM.pdf Newton, C. (2014). Lateral Supports. Retrieved from Learning Management System Constructing Environments: https://app.lms.unimelb.edu.au/webapps/portal/frameset.jsp?tab_tab_group_id=_5_1&url =%2Fwebapps%2Fblackboard%2Fexecute%2Flauncher%3Ftype%3DCourse%26id%3D _271852_1%26url%3D Newton, C. (2014). Short and Long Columns. Retrieved from Learning Management System Constructing Environments: https://app.lms.unimelb.edu.au/bbcswebdav/courses/ENVS10003_2014_SM1/WEEK%2 005/SHORT%20AND%20LONG%20COLUMNS.pdf Newton, C. (2014). Span and Spacing. Retrieved from Learning Management System Constructing Environments: https://app.lms.unimelb.edu.au/bbcswebdav/courses/ENVS10003_2014_SM1/WEEK%2 004/SPAN%20AND%20SPACING.pdf Newton, C. (2014). W03_c1 Footings & Foundations. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=PAcuwrecIz8&feature=youtu.be Newton, C. (2014). W03_m1 Introduction to Mass Construction. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=8Au2upE9JN8&feature=youtu.be Newton, C. (2014). W03_m2 Introduction to Masonry. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=DC8Hv8AKQ8A&feature=youtu.be Newton, C. (2014). W03_m3 Bricks. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=4lYlQhkMYmE&feature=youtu.be 183
Newton, C. (2014). W03_m4 Stone. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=2Vn5_dk4RtQ&feature=youtu.be Newton, C. (2014). W03_m5 Blocks. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=geJv5wZQtRQ&feature=youtu.be Newton, C. (2014). W03_s1 Structural Elements. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=wQIa1O6fp98&feature=youtu.be Newton, C. (2014). W04_c1 Floor and Framing Systems. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=otKffehOWaw&feature=youtu.be Newton, C. (2014). W04_m1 Concrete. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=c1M19C25MLU&feature=youtu.be Newton, C. (2014). W04_m2 In Situ Concrete. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=c3zW_TBGjfE&feature=youtu.be Newton, C. (2014). W05_c1 Walls, Grids and Columns. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=Vq41q6gUIjI&feature=youtu.be Newton, C. (2014). W05_m1 From wood to timber. Retrieved from Learning Management System - Constructing Environments : http://www.youtube.com/watch?v=YJL0vCwM0zg&feature=youtu.be Newton, C. (2014). W05_m2 Timber Properties and Considerations. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=ul0r9OGkA9c&feature=youtu.be Newton, C. (2014). W05_m3 Engineered Timber Products. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=0YrYOGSwtVc&feature=youtu.be Newton, C. (2014). W06_c1 Roof Systems. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=q5ms8vmhs50&feature=youtu.be
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Newton, C. (2014). W06_m1 Introduction to Metals. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=RttS_wgXGbI&feature=youtu.be Newton, C. (2014). W06_m2 Ferrous Metals. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=SQy3IyJyis&feature=youtu.be Newton, C. (2014). W06_m3 Non ferrous Metals. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=EDtxb7Pgcrw&feature=youtu.be Newton, C. (2014). W07 m_2 Plastics. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=5pfnCtUOfy4&feature=youtu.be Newton, C. (2014). W07_c1 Detailing for heat and moisture. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=Lhwm8m5R_Co&feature=youtu.be Newton, C. (2014). W07_m1 Rubber. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=OPhjDijdf6I&feature=youtu.be Newton, C. (2014). W07_m3 Paints. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=WrydR4LA5e0&feature=youtu.be Newton, C. (2014). W08_c1 Openings: Doors and Windows. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=g7QQIue58xY&feature=youtu.be Newton, C. (2014). W08_m1 Glass. Retrieved from Learning Management System Constructing Environments: http://www.youtube.com/watch?v=g7QQIue58xY&feature=youtu.be Newton, C. (2014). W09_c1 Construction Detailing. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=yqVwAV7yJCI&feature=youtu.be Newton, C. (2014). W09_m1 Composite Materials. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=Uem1_fBpjVQ&feature=youtu.be
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Sadar, D. J. (2014). Glass Skins. Retrieved from Learning Management System - Constructing Environments: http://www.youtube.com/watch?v=NW_GibnyBZc&feature=youtu.be The Concrete Society. (n.d.). In Situ Columns. Retrieved from Concrete.org.uk: http://www.concrete.org.uk/fingertips_nuggets.asp?cmd=display&id=353 The University of Melbourne. (2012). Parkville Campus. Retrieved from Maps: http://maps.unimelb.edu.au/parkville TimberDesignAwards. (2010). Frank Tate Pavilion. Retrieved from http://www.timberawards.com.au/frank-tate-pavilion WebFinance Inc. (2014). Dictionary of Construction.com. Retrieved March 15, 2014, from http://www.dictionaryofconstruction.com/ Wood & Grieve Engineers . (n.d.). Oval Pavilion Construction Drawings.
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Appendix Construction Workshop At the construction workshop, we were divided into groups and told to construct a structure that spans 1000mm. Materials and tools used
2 boards of plywood 42m x 19mm x 2.4m 2 boards of pine 1200 x 42 x 18 Hammer Screws Nails Saw Drill
Below is a diagram of our idea of what we wanted the structure to look like. Figure 245: Intended structure
We used the thicker pine for the whole structural system and used the thinner plywood for bracing so that the structure will be more stable.
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Building the structure The pine was cut into two equal lengths to form the two sides of the triangle. We used the second piece of pine as the base, and then the remaining pieces from the pine to support the base. Figure 246: Sides of the triangle
Pieces of pine for the sides of the triangle. They were cut at an angle at the bottom to facilitate attachment to the base
Figure 247: Structure
Thicker pieces of pine to form side of triangle Plywood to form bracing, which will cause the load needed to break the structure to increase by providing structural stability
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Joints Screws were used to connect the sides of the triangle to the base and to each other, and smaller nails were used to fix the bracing together. Figure 248: Joints
Fixed together with screws and a hammer
Fixed together with nails and a hammer Fixed together with the drill and screws
Figure 249: Final structure
Pine for the two sides of the triangle
Plywood bracing Base for the structure
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Structural performance and failure mechanisms Our structure was able to take a maximum load of 240kg before a structural failure occurred. The maximum deflection of the beam, on which the triangle was mounted, was 20mm. This large deflection may have occurred because of the way the beam was placed. Figure 250: Placement of beam
Beams are in this manner, as more surface are receives the load, which may cause bending. This caused the large deflection of 20mm
If beams were placed in this manner, less surface are receives the load, which would have minimized bending.
The failure in our structure was the joints, because at 240kg, the screws connecting the two pine members together got detached. If the screws had been drilled down instead of being hammered, in, it is possible that that may have resulted in a more stable structure.
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Analysis of key concepts Span All structures had to span 1m. If we had been able to decrease the span, there may have been less deflection of the beam. Figure 251: Deflection of beam with increased span
Figure 252: Reduced span
Increased deflection with increased span of beam
Reduced deflection with decreased span of beam
Shape and strength Our structure could have been improved by providing additional bracing using the plywood boards. Because the load applied was directed right to the top of the triangle, additional bracing would have helped withstand a larger amount of load and increased the strength of the structure as a whole. Figure 253: Shape and strength
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Material efficiency The fact that our structure was able to withstand 240kg indicates that the materials were efficient in terms of forming a stable structure. However, if we had connected them properly and used the remaining plywood to form bracing, the structural performance of the structure may have been better. Joints All the joints in the structure were pinned joints, because the members would still be able to rotate if they were not connected at two ends. The structure did fail due to the joints, which may have been improved by making them with the drill instead of the hammer, Figure 254: Pinned joint
Comparison with other structures Figure 255: Team 1 structure
Beam has cracked due to load Joints have failed in this section (similarly to ours), indicates that members were not joined together properly
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High deflection of beam due to the way it was placed (similar to ours)
Figure 256: Team 3 structure
Joints came apart with increased load – however, was not the main cause of structure failing
Shape was similar to ours Beam splintered with increased load showed failure of materials Figure 257: Team 4 structure
Beam cracked in the middle with increasing load – may have been able to withstand higher loads if there was support underneath
Comparison between working with actual construction materials as opposed to scale model making materials
Examples of construction materials include brick, concrete and steel, and examples of materials that can be used for scale model making are balsa wood, cardboard, pine and plywood. Construction materials will have a much higher strength than scale model making materials, and would need a substantially larger load to destroy structures made compared to model making materials. However, they are more difficult to work with. Cutting concrete, for example, will be more difficult than cutting balsa wood. As a result, it takes a longer period of time to build structures with construction materials than with model making materials.
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