I have some great news to share! There is a replacement for the old Bridge Designer which no longer works on modern web browsers. The new pony in town is called the Truss Simulator. Like before, it is freely hosted on the Johns Hopkins website, and created by Claire VerHulst.
This new Truss Simulator brings more features and flexibility than the old version. Check out my tutorial videos below:
So when using this tool, I would assume that each side of the bridge takes half the load. Also if you have a plate that is being used to load a bridge in a competition how would you show the part that one side of the bridge would carry? (I have ideas but I’m interested in your take).
Yes, great point there. Each side of the bridge ideally takes half the total weight on the bridge. Believe it or not, this didn’t immediately sink for me in my first bridges back in middle school. I overbuilt them because of this. It is possible that in practice one side of the bridge has more than half the load, but you shouldn’t plan on that.
Unfortunately this tool is limited to loading at points (nodes). You can still get a fairly accurate picture by loading up multiple nodes, the size of your plate. Obviously the total load you use will need to be spread out between the loaded nodes.
Thanks for the confirmation. The plate is 40×40 mm which makes it a little smaller than actual node spacing in current design. I’m experimenting with adding “fake” nodes in the tool to distribute loads but the 2*n-3 members requirement makes that tricky.
I suggest changing your design so that the nodes are spaced closer together. If the plate is not directly supported by your truss, it will be likely to fail in shear. You will need to beef up the area spanning the two closest nodes to the plate, which is generally not as efficient as designing your truss to support the plate.
How I will analyze and optimize the truss, can the simulator help with that? Can you please provide the video link of you other tutorials of the simulators please.