Reliability Engineering. Seismic Reliability Analysis and Reliability-Based Design of Steel Piers of Highway Bridges.

Many highway bridges were damaged by a great earthquake that hit west part of Japan on Jan. 17, 1995. Especially, steel as well as RC pier structures designed according to the old versions of design codes were injured. It was pointed out that the reliability level was different depending on each version of design code as well as types of structures. In this study, in order to know the reliability level of pier structures designed according to each version of design codes that have been used before 1995, reliability analyses were performed at first yield limit state for typical types of steel rigid-frame piers selected out of existing bridge piers. It was verified that the reliability level of pier structures designed according to 1964 version was lowest. Further, several shortcomings inherent in the current design codes based on the allowable stress design method were pointed out.