Prestressed Concrete Bridges

Beginning in 1946 in the U.S. and growing rapidly for 30 yr, Prestressed Concrete Bridges of many types have become commonplace in the U.S. These have evolved through small simple span bridges through major projects, and today some of the largest projects ever built are being designed in Prestressed Concrete. Precast Prestressed Beam Bridges of the longitudinal box or AASHTO I-Beam cross-section have led in number of bridges. These are not always simple span bridges. Post-tensioned cast in place bridges of the box girder variety have become most popular especially in the western part of the U.S. Combinations of precast and cast in place with post-tensioning are increasing daily. The latest developments for long span bridges are Segmental Box Girder Bridges. Nearly fifty of these are built or under design in the U.S. today, and the number will steadily grow because of the many advantages offered by this type of prestressed concrete bridge.