The objective of the project is to build a truss that would be able to take a specific amount of downward force remarkably with respect to the weight of the truss itself, i.e. to construct a truss that would hold a relatively high efficiency score. And construct the bridge in such a way to as to keep the deflection of the structure at minimal.
First of all, what is a truss? In an engineering view, a truss is a structure that is made up of series of triangular unit made of straight members that are connected at junctions known as nodes. External forces created by bodies known as loads, are often placed on areas of the structures which then creates internal forces in the members in form of either a Tensile Force or a Compressive Force. The practical analysis was carried out to help better our understanding on the theories behind the behaviour of a truss under different circumstances.
A Pratt truss illustrating the arrangement of the bars
The length of the horizontal member is 99.4m
The height of the bridge is 20m.
And the diagonal members are all 23.6m
The distance between the two sides (floor Beam) was 16m.
Today, bridges can be of the span, arch, or suspension type. Materials used throughout history include wood, masonry, cast iron, wrought iron, concrete, steel, reinforced concrete, alloy and silicon steel, pre-stressed concrete, carbon fibre, and aluminium. But since the experiment was to be performed in a small scale, Popsicle sticks where chosen to do the job. Then a non-toxic adhesive was chosen to be used to join the members at the node. A clamp of some sort is a good idea when constructing. Clamps are important because most of the popsicle stick aren't flat, so if you don't clamp them when you glue them together your bridge probably won't hold together very well.
The bridge truss was constructed using about 140 sticks, give or take a few. We began the construction...