Truss Bridges
Truss bridges are, as their name would suggest, made of trusses. By making several small beams act as one, larger beam, a truss uses less material and can handle heavier loads. Truss bridges are short bridges. Small parts of the truss are referred to as members of a truss. Each member of a truss has a different job, and the members work together to carry heavy loads.
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There are many different truss designs, with the Warren, Pratt, Howe, and K-truss being the most basic. Below, they are pictured in order from left to right, and top to bottom.