Hi PIL participant!
Thinking of Jim's great series on bridges! The collapse of the Washington bridge shows how difficult it is to build a lasting bridge?
There is an iPad game called "bridge constructor" that let's you build a bridge and then drive trucks over it. You are given a budget and plan the materials etc yourself. Often the bridge falls down even before the vehicles get on the bridge?
I have watched many bridges collapse because the game is a challenge!
Arthur