The Rio Grand Gorge Bridge (near Taos, NM) The Los Alamos Bridge (The Omega Bridge - Los Alamos, NM)
Notice the Rio Grand Gorge Bridge (LGGB) has diagonal bracing but the Los Alamos Bridge does not?
What makes it possible to leave out the diagonals in the Los Alamos Bridge (LAB)?
A curved deep beam and two hinged supports.
The Omega Bridge is essentially a beam with vertical struts extending up to the road bed.
The Rio Grand Gorge Bridge is a truss - continuous over two interior hinge supports. The top chord of the truss is a beam supporting the roadbed.