Extending span ranges and accelerating construction of spread slab beam bridges

A new class of spread slab beam bridges has recently been developed and implemented in Texas. The research questions addressed in this paper are: how long can such a low profile bridge system span in either a simply supported or continuous form? And, can construction operations be accelerated, by design? An effective way to extend the span length is to utilize post-tensioning and to make the bridge continuous over several spans. In order to explore the maximum span limit, the design of a multi-span prestressed concrete spread slab beam bridge is investigated. In addition, a thicker and longer precast prestressed concrete panels (PCPs) that uses concentric pre-tensioned prestress is developed to facilitate accelerated bridge construction by reducing the need for field placement of deck reinforcement. It is shown that the span length may be extended from 15 m to 21 m as a continuous shallow profile bridge. The new solution for PCPs is verified to speed up field operations as compared to the traditional deck with stay-in-place PCPs and cast-in-place toppings.