Science in term 4 saw us building, researching, engineering, trying, failing, and trying all over again. The action-packed curriculum was an experience for us all, be it through how much we learnt about earthquake proof buildings, or developing the steady hand needed for assembling spaghetti and blue tack into a building with the structural integrity required to withstand an earthquake imitation from the earthquake simulation table.
The basic challenge we were given on this task was to research earthquake proof buildings, strong shapes and designs, and applications of these in real life. Then, to design a building of our own. We could only use blue tack and spaghetti. The next step was to test the building and see its earthquake proof capabilities. Finally, acknowledge its flaws and design an amended version of the building with problems from the first one eliminated, and re-test, all whilst keeping under the $60 resource budget limit. The success criteria of the build was that:
- The base must no larger 30cm x 30 cm.
- Height of the build must be at least 60 cm.
- Must remain standing above 60cm after the earthquake simulation.
- $60 budget:
- $1 for every 10cm spaghetti.
- $1 for every gram of BluTack.
Although we weren’t buying the spaghetti and blue tack ourselves, a budget limitation was put on us to simulate the cost of resources in real life and teach us to find the balance between spending money to fortify the build, and being able to use innovative, cheap designs to still withstand earthquakes.
The process begun with a research task, which gave us all the information we needed to know about the techniques and methods applied in real life to give buildings a chance against earthquakes. Jotting down our knowledge after some brief research produced this mind map shown above. This was a basic run down of the components we would focus on for the task. After doing some more in-depth research, we discovered more about specific features buildings use to prevent earthquake damage.
Often, pylon-like foundations are present that are drilled down into bedrock, to secure the building. Otherwise, the loose topsoil would not provide a very stable ground, especially when liquefaction comes into play. Another technique is base isolation foundations. These are flexible pillars that the building is built on, that, when affected by tremors, counteract the force be vibrating in the opposite direction. This cancels out the force of the tremor, meaning the building on top is barely affected. The structure of buildings is reinforced to prevent drastic effects from earthquakes. These reinforcements include bracing of the building walls with a scaffold-like framework. These are known as cross braces. The force of the quaking is distribute amongst the cross braces, which dissipates it more effectively. Diaphragms are another type of grid-like structure to prevent earthquake damage in buildings. A diaphragm is a horizontal frame placed below a slab of a building. They help to remove tension from the floor. These are just a few of the methods architects use while designing buildings in earthquake prone areas. The rest of the researched methods were ones that wouldn’t be relevant to our building, as they would be too complex to recreate with spaghetti.
The next part of the process involved coming into groups, assigning roles to each group member, and beginning to plan and budget our design. After 3 iterations, we settles on a design we were all happy with. Our first design was to feature a hexagon base, but this would be too expensive, and a six faced building would use a lot of spaghetti. The second design involved a triangular base, and three main layers. The first of which tapered in, the second went straight up, and the third tapered in once again. It also had cross braces that fortified the build between each layer. We ended up settling for a design similar to this, except the building tapered from the bottom to the top consistently. This design was our final design, and is shown in the diagram above as well as the picture below. The cross beams all go in the same direction around the build (all the builds faces look the same if this makes sense) and, although not visible in the photo due to the lighting, there was a large BluTack piece on top of the tower as an embellishment. This caused it to be top heavy. It was 66cm tall. We stuck to our plan throughout the building process, and had a triangle base with the shape tapering. We stuck to the cm measurements of the spaghetti, also, and were 1 dollar and 10 cents under budget. There are a few changes I would’ve made to this part of the process – I wish we had more time to build the building, rather than rushing it in one lesson. The finished result was slightly wonky on the second layer, which meant all the structure above that layer didn’t have as much integrity. Additionally, extra time in the planning phase would’ve allowed us to test multiple designs, rather than just the one. This way, we could’ve seen which features worked and didn’t work, and optimised those to combine them into one design that had a much greater chance of survival.
Unfortunately, after the long process we had gone through of building our tower, it didn’t survive the table. The building survived until about 5-10 seconds into the shaking process. This was largely due to an embellishment of BluTack on our build. It made the build top heavy, and in shaking it collapsed the top part of the structure.
In order to improve our plan and design before building it again, we went over the positives and negatives of it. The advantages included: ample triangles used in the build, under budget, met all the size criteria before going on the earthquake table, simple design, not too difficult to build. The disadvantages included: was top heavy, collapsed on earthquake table, had a few blue tack joints with many, many spaghetti pieces connecting to it, all cross beams were going in the same direction; building twist folded. We formulated a new plan, as seen with the purple highlighting all our changes in the picture below.
Our second design still didn’t survive the table, but it lasted much longer. The changes we made to the building were very beneficial; even though it didn’t survive the earthquake table. The building was clearly much stronger, and this was largely due to the new positioning of our cross beams.
The specific changes we made included the following:
- We changed the direction of some cross beams. When they were all going the same direction, the turbulence throughout the build caused to fold and twist up, and the uni-directional cross beams just contributed to this. Having some cross beams going against this force allowed the building to not twist.
- We made the building less top heavy. This way, the top didn’t wobble as much on the earthquake table, causing less pressure on the BluTack below it.
- We built it in a different order. We made it more of a modular build, building pieces together separately and then placing them on each other, rather than building them altogether and on top of each other at once. This way, less pressure was put on the lower down pieces of BluTack during the building process.
Throughout the task, I wish we had spent more time designing and testing, as our building may have had a better chance. Additionally, I think our group specifically might have been more successful if the base of our build was wider. It would have been really interesting to attempt making some of the earthquake prevention methods out of BluTack, like shock absorbers are or base isolation foundations. This would have been difficult, but with a bit of innovation and creativity it would’ve been possible and very cool to see.
Overall, the task was incredibly beneficial, and I learnt many lessons of teamwork, collaboration, and resilience. The task also expanded my knowledge of earthquakes themselves, and the interesting techniques used to counter them. In addition to all the knowledge and skills I gained from the task, my group and I had a fantastic time working together to build earthquake proof towers out of spaghetti and BluTack.
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