Planning
What we wanted to achieve
We wanted to design and create a structure that is able to withstand a simulated earthquake while only being made from limited amounts of spaghetti and blue tack. Success in this goal would include the structure staying up with minimal damage to critical components and minimising bending and movement.
Designing such a structure with such success parameters as the same conditions created in a real earthquake is essential. For example, in this scenario and real life, we are trying to make the structure stay in the air.
Our first test and what we learned
During our first lesson, we completed a prototype (speed run) this ended poorly as the structure bent over. The uneven distribution of weight caused this. For our final design, we will make sure that all the weight is balanced inside of the structure.
Our research and what we learned
During our research, we came across three design features often used in earthquake-resistant engineering, which we can apply to our scenario.
These are;
Diaphragms
A diaphragm is a structural element that transmits lateral loads to the vertical resisting elements of a structure. This will help us to disperse the earthquake’s force throughout the structure. This will minimize the risk of too much force building up in one spot, causing a break in the structure.
Cross-Bracing
A cross-bracing system features diagonal supports that intersect. This will help us to reinforce the structure, providing more strength and stability to all of its components.
Trusses
Trusses are diagonal structures that fit into rectangular angles of the frame. They are used to add strength to the weakest parts of the diaphragm. This will help us to make sure the diaphragm does not break.
The Design we went with
After our research and first prototype, we decided to utilise the Diaphram and Cross Branching Design Techniques. We also decided to use this design.
Materials Needed
30 pieces of Spaghetti
23g of blue tack
Experimenting
Results of the first build. Complete structural collapse.
Causes of failure and difficulties in consruction
The use of the diaphragm design feature (The Rod in the middle of the building) the structure was not stable during construction. This made it almost impossible to build the rest of the structure as it all relied on the stability of that design feature. For our next model, we removed this design feature replacing it with multiple supports for all connection points.
Our group’s lack of implementation of cross-beaming in our prototype again caused a severe lack of stability leading to immense difficulties in constructing a design of such a large height and surface area. For our next model, we increased the use of cross-beaming as to increase stability.
Our new design
What new and why
Removed Diphram
We removed the singular upward beam in the middle of our design. We did this because, in our previous design, it was the main point of failure. Removing this design element and replacing it with multiple different connections should help to spread the force more evenly. This should lead to fewer points of failure.
Changed Shape
We Changed the shape in two ways. First, we made it so that the structure gets smaller as it goes up. We did this to keep the centre of mass low. This should stop the building from moving and swaying as much as when it was first built. Second, we changed the shape from a square to a hexagon. We did this to add more connections holding up the structure. We believe this will give us more backups in the event of a failure as well as make it much easier to build as the structure should be able to support itself much earlier.
Added Cross Beaming
We added more cross-beaming to our design. This was done to increase the stability and sturdiness of the structure as well as to help minimize the previously described bending. This will make it easier to build as well as make the structure a lot more stable overall.
Results of the second build and how are changes effected the structrue
The building again suffered a complete structural collapse.
Removed Diphram
The replacement of the diaphragm lead to fewer points of failure causing much fewer pastas to snap.
Changed Shape
The change of shape led to the failure of “some” connection points not causing a complete collapse, however, it did not stop the failure of nearly all connections causing the collapse.
The other change of shape led to the building process being slightly easier, however, it did not lead to any discernable stability change
Added Cross Beaming
The addition of extra cross-beaming led to extra stability and sturdiness of the structure; however it did not stop the twisting of the structure.
Review
Through the project me and my team learned a lot about teamwork and the design process. We all brought different abilities to the group, from creative design and ideation through Rhys, technical ability through Dylan and research and time management through me. If I was to complete a similar project again, I would change our process for creating the structure by, collaborating more on designs, researching similar projects in more detail, focusing on how design features are implemented and finally, spending more time prototyping.