The Truss Bridge belongs in the Beam Bridge family. The example here is a Through
Truss Bridge. So called because the traffic passes through the superstructure. If the bridge
was inverted (the other way up) it would be a Deck Truss Bridge. The beam bridge is the
earliest form of bridge and its origins are in pre-History. A tree fallen across a stream is a
simple Beam Bridge so it is highly likely that our ancient ancestors were using this type
of bridge while they were still dwelling in caves.
– The deck of the model is a 9 1/2″ x 2 1/2″ Strip Plate overlapping a 4 1/2″ x 2 1/2″ Flexible
Plate by 3 holes.