Engineering Physics – I finally built my bridge testing apparatus. A bottom beam sits on two bathroom scales. Another beam slides on threaded rod which is attached to the bottom plate, and by tightening the nuts on the rod, the top beam compresses the bridge truss and bottom beam against the bathroom scales.
The bottom picture shows the bridge truss that withstood the greatest force. Lots of bridges failed at glue joints which surprised me. I need to look into that for next year.