Week 7

Last week in lab we got to test our bridge design.  The bridge we tested was 2 feet long.  The bridge had an under truss, which when tested the bridge broke where the under truss ended.  The reason we put the under truss in was so that it dispersed the weight.  When tested our bridge held about 39 pounds.  The problem was that the bridge was way too expensive.  I think our bridge ended up being the most expensive in the class, which was about $380,000. The amount of joints used is what gave the bridge most of its cost.  To combat this we decided that we have to make our members longer so that we used fewer pieces therefore making the bridge less expensive.  Since the weakest points on the bridge is the gusset plates we will have to come up with a solution to make them stronger some how.

            As far as numbers go I would like to see where the most compression and tension is on the bridge.  This is so we can see where to add more supports and even take pieces off if they do not add any support.  This would also be great to see if other designs work better.  The only way I can think to test of compression or tension is to feel for it.  You will have to try and bend members with your hands and see which ones resist the most.  Unfortunately you cannot see all calculations in real life like you can in Westpoint Bridge Design.