02-20-2009, 11:28 AM
I'm no structural engineer, although it sure is great to hear from an expert! I just use common sense and observation when mixing materials, whether it's a bridge or a building.
You will see stone foundations supporting wood structures. Wood supporting stone - never. Wood supporting steel - that doesn't work either. Curved bridges are not really curved, but a series of angled straight sections. Think of a brick arch. It is a curve, but the bricks that make it up are still straight, they are just angled (except to the keystone of course which is angled on both sides).
There may be exceptions to this, but I think it's always more believeable to go with standard practice rather than hunting for some unusual prototype to justify "breaking" the rules.
As for mixing truss bridges with timeber trestles, there were many instances of truss style bridges being built of timbers. There are even kits of wooden truss bridges. <!-- m --><a class="postlink" href="http://www.walthers.com/exec/productinfo/472-3053">http://www.walthers.com/exec/productinfo/472-3053</a><!-- m -->
cheers
Val
You will see stone foundations supporting wood structures. Wood supporting stone - never. Wood supporting steel - that doesn't work either. Curved bridges are not really curved, but a series of angled straight sections. Think of a brick arch. It is a curve, but the bricks that make it up are still straight, they are just angled (except to the keystone of course which is angled on both sides).
There may be exceptions to this, but I think it's always more believeable to go with standard practice rather than hunting for some unusual prototype to justify "breaking" the rules.
As for mixing truss bridges with timeber trestles, there were many instances of truss style bridges being built of timbers. There are even kits of wooden truss bridges. <!-- m --><a class="postlink" href="http://www.walthers.com/exec/productinfo/472-3053">http://www.walthers.com/exec/productinfo/472-3053</a><!-- m -->
cheers
Val