Construction Issues in Steel Curved-Girder Bridges

Abstract

The construction of horizontally curved steel bridges is generally more complex than the construction of comparable straight-girder bridges of similar span. Curved-girder bridges, once completed, have generally performed as intended. Most problems that have occurred with curved-girder bridges have been related to fabrication and assembly procedures or unanticipated and unaccounted for deformations that occur during construction. As a result, these construction issues take on primary importance in the successful completion of the structure. Successful completion requires that each phase of construction proceeds as anticipated to ensure that the final structure is at the correct elevation to provide proper deck drainage and good riding quality. In some cases, construction issues for curved bridges have been given little or no special consideration by designers, or, at the very least, no more consideration than has been given to these issues for straight bridges. Thus, there is a need to better identify these issues, assemble and provide more in depth information on each of these issues to the design community, and emphasize their importance to designers. The significance of construction issues to complex horizontally curved steel bridges is in many ways analogous to their prominence in the design of segmental concrete bridges; construction issues often drive the design decisions. The objective is to promote awareness in the design of horizontally curved steel bridges to some of these construction issues.