I need to build a bridge that supports 50 grams of weight (half a penny roll) mad of straws, paper clips, tape

Question

, pipe cleaners, that is 5cm high and spans 40 cm. How do I do it?

Please Help!!!!!!!!!!!!!!

Answer 1

Well, this might be tough. The bending moment in the middle of the span will be 50 gram x 20 cm = 1000 gram * cm. Thus, the minimum compession and tension forces for a 5 cm high will be 1000 gram * cm / 5 cm = 200 grams.

Thus this structure will behave more like a beam than a truss.

Pipe cleaners can be used for the bottom chord (tension), double straws (crinkle one straw inside another) pinned with paper clips can be used for the top chord (compression) and diagonals.

The compression members will be subject to buckling and can't be too long. You can do experiments with 200+ grams to see at what length buckling occurs for your chosen member.

The ends of the structure will be in shear with a 50/2 gram load.

Good luck.