Introduction - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 14

Figure 1.15 An orthotropic steel floor truss bridge ( steelconstruction.info ).

Figure 1.16 A semi-through truss bridge under construction ( steel-trussbridge.com ) .

are the bridges having their carriageway resting between the bottom and top
levels of the main structural system and the top level of the main structural
system is below the carriage, with an example shown in Figure 1.16 . In this
case, a top-bracing system cannot be installed at the top level of the main
structural system. Finally, pony bridges are semi-through bridges having
their carriageway resting on the bottom level of the main structural system
and the top level of the main structural system is below the carriage as shown
in Figure 1.17 . In this case, similar to semi-through bridges, a top-bracing
system cannot be installed at the top level of the main structural system. It
should be noted that most of modern bridges are fabricated in workshops
and transferred to the construction field. Also, most of modern bridges
are fabricated such that the main structural system components are