We were assigned with a task of building a small-scale structure that could withstand a simulated earthquake, through a shake table. We had to follow the design brief provided building the structure out of pasta and blu-tack which had a minimum height of 60 cm and a maximum base of 30 cm x 30 cm. We had to also stay under a budget of $60, the costs for each material $1 per 10 cm of pasta and 1 gram of blu-tack. The idea of this project was to research and design architectural features in our structures, which could possibly influence the design of buildings in earthquake prone areas.
We first started tackling this challenge through gathering information, researching prominent and influential design features of buildings in earthquake prone areas. The first place we thought would give us a head start was Japan, a significantly prone area to earthquakes. We found many prominent design features in high rise buildings and skyscrapers in Japan that would influence our design. Some of these designs included: base isolation, concrete cores, and dampers.
Through researching these different design features, we were able to apply them to our first design ideas that we planned. First we thought of building our structure around a heavily structured centre, then sticking pasta sticks around it to distribute the weight and achieve the height, this was heavily influenced by the concrete core design as seen above. Another idea we had was to build our structure isolated from the ground, so that the main structure would not fully connect to the ground. We also would add extra pasta materials inside the structure to provide extra stability to the design. This idea was influenced by Japan’s use of damper beams and base isolation as seen above.
After creating detailed diagrams of our designs (as seen above), we realised that if we were going to move on to creating the structures, we would be faced with many problems. The main problem with both of these structures was that the design had to be built within a budget of $60. We had assumed that one pasta stick would only cost us $1, when actually we could only buy 10 cm of pasta with $1. (This is an example of what we could do differently, if we were to tackle this project again). This problem could have likely been prevented if any of the members in our group communicated effectively with the teacher and payed attention to the design briefs before diving into the project quite blindly. With this abrupt roadblock we faced, we were then forced to change our design ideas, focusing more on how much materials we used and different shapes we could base our structure off, as the rectangular shape would be too expensive. As an alternative, we began researching again for a structurally stable shape design. As it turned out, most structures in earthquake prone areas were built like triangles. A good example of the is the Transamerica pyramid in San Fransisco.
This skyscraper contains 48 floors, 260 metres high. As you can see from the image, this building is built like a triangle, The width becoming more and more thin from the base up as the height increases. It is also important to note that this building had withstood the Lomo Prieta earthquake of 1989. The wide base of the structure is what gives it it’s stability. From research on this specific design feature we quickly pivoted to another idea, this time basing our structure more on a more triangular shape. This led us to creating our next designs as seen below.
Once my group realised our first design had not worked, we immediately abandoned it and started working towards designing a new structure. At this point my group was showing much more efficiency and motivation to get our structure to work. We also became more aware of the imminent deadline, which pushed us to stay focused and on task. Each team member effectively filled out their roles. The equipment manager gathered the necessary amount of materials and accurately built the structure, the speaker made sure to communicate with our science teacher, making sure that we were following the design briefs correctly. The reporter made sure that the final structure being built before the due date was realistic, and the project manager made sure that everyone stayed on task rather than procrastinating or wasting their time in other ways.
In our new design, the triangular influence helped with creating support in our structure. We still hadn’t abandoned aspects of our previous research of Japan’s earthquake proof buildings, using excess pasta sticks to add dampers at the base of our structure. This helped create a solid support that would ground the structure when being shook. Our new structure also managed to follow the design briefs, achieving a height above 60 cm and a base below 30 cm by 30 cm. This design was also significantly cheaper than our first design that we went with, using less materials. An example of this was, to achieve a height of 60 cm in the cheapest way possible we only stuck one pasta stick of 25 cm on the top of the structure to save us materials. After building this structure we went to test it out on a shake table, designed to simulate an earthquake. The results are shown below.
After we had tested how our structure would handle an “earthquake”, we used a phone to record what magnitude our structure could withstand. From this diagram you can see that the structure could withstand a maximum of 8 magnitude. We found that the structure was strong against horizontal movements/tremors, but became weak from vertical movements/tremors. Towards the end of the test, one of the top pasta sticks became unstuck, collapsing the top part of our structure. We only had a few days left to go to the final due date of the structure, so after a good attempt we decided to further see what improvements we could make to the structure, to make it more stable (especially at the top).
This was the final design we came up with in the end. The improvements we made were, widening the top base of the structure to create a better support at the top, using less blu-tack to ease up weight/force pushing down on the structure and being more accurate when building our structure. Another challenge we faced at this point was that 2 of our team members were away, leaving only my other team member and I to build our final structure on our own. We managed to get through this by staying focused and helping each other out on building the structure so it could reach its maximum potential.
In the end, we managed to build the final structure as seen in the image above. We tested the structure and it stood standing after aggressive shakes/tremors both vertically and horizontally. The magnitude reading was marginally better reaching a max of 8.3. The final structure also stood at a height of 65 cm and had a base of 27 cm by 27 cm. After the testing on the shake table, our structure also stayed intact and solid, a good sign that our design would most likely survive a large scale earthquake.
I have learnt that teamwork and communication is key for group projects where you want the end product to turn out impressive and well-made. At the start of the project we weren’t very motivated, also influenced under the mindset that building the structure would be quite easy. The realistic fail of our first design and the push to get our structure built on time helped us gain some focus and guide us on the right direction to creating an effective and stable structure. My team members always made sure that they were being useful at most times and put much effort into creating the end product. Although, our structure did not turn out to be as solid and structurally stable as a rock, it did achieve the given design brief and withstand the violent shakes of a simulated earthquake, proving itself a worthy design for structures to be built in earthquake prone areas.