Engineering Statics Bridge Project
In my engineering Statics course, we learned about the physics and analysis of static structures. The course description is as follows:
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Introduction to engineering analysis using the principles of engineering solid mechanics. Builds on the math and physical reasoning concepts in Physics Mechanics to develop skills in evaluation of engineered systems across a variety of fields. Foundational ideas for more advanced solid mechanics courses. Interactive lecture sessions focused on mathematical application of key concepts, with weekly complementary lab session on testing and designing systems that embody these concepts.
For our final project in this class, my team of four people had to build a truss bridge to certain specifications and a target failure load. We came up with several different designs for our bridge, weighing in both the uniqueness of design and the estimated strength to weight ratio. We modeled three designs in Mastan to test the loads that they could withstand before failure, based on the Modulus of Elasticity of the material.
We finally decided on a design to pursue, and proceeded to perform a full structural analysis of the trusses to find the exact force on each member. We calculated which trusses were in tension and which were in compression, and which members we predicted would fail first under a specified load, an how they would fail. After the analysis, and after adding a factor of safety to the structure, we printed a 2D scaled drawing of the structure to base our cuts off of, and cut each member from balsa wood using wood glue adhesive to connect at the joints. We then added gussets to the bottom joints.
Our structure was tested using a Vernier Structures and Materials Tester in class. The load was evenly distributed on the bridge, and gradually increased until failure. The load was displayed on the projector as it was increased. Our structure failed at a load of 124.21 Newtons, higher than our predicted failure mode. With a weight of 4.5 g, it meant our structure had an efficiency of 2728.682%, and was in the top five structure in the class for its strength-to-weight ratio. A link to the final report is below.
