Progress in Structural Engineering and Materials: Concrete Construction - Precast concrete bridge systems optimization

摘要

There are three main types of concrete bridges in the United States. These types are cast-in-place, precast and special long span bridges. The focus in this paper is on precast concrete bridges, especially precast concrete I-girder bridges. The design of I-girder bridges can be optimized by increasing the area of the bottom flange, by using welded wire reinforcement for shear reinforcement, by using high-performance concrete, or by splicing the I-girders. Stay-in-place deck slab forms or full depth deck slab panels are used to achieve rapid construction, improve safety and reduce the cost of the deck slab removal.rnIn order to increase precast concrete I-girder spans while minimizing the superstructure depth, four different systems for creating continuous spliced concrete I-girders are presented. The first system is limited to spans where full-span segment lengths are spliced over the piers. Within the first system, three different methods of continuity are presented. The other three systems are cantilever type bridges which utilize post-tensioning of partial span segments, with prismatic or non-prismatic pier segments. Comparisons among the system capacities are presented. Details of a specific bridge (Highland View Bridge) are presented here, to provide an example of spliced precast I- girders.