GEOTECHNICAL RELATED DEVELOPMENT AND IMPLEMENTATION OF LOAD AND RESISTANCE FACTOR DESIGN (LRFD) METHODS

This synthesis report will be of interest to geotechnical, structural, and bridge engineers, especially those involved in the development and implementation of the geotechnical aspects of the American Association of State Highway and Transportation Officials (AASHTO) Bridge Code. The synthesis documents a review of geotechnical related load and resistance factor design (LRFD) specifications and their development worldwide in order to compare them with the current AASHTO LRFD Bridge Code. Design procedures for foundations, earth retaining structures, and culverts are summarized and compared to methods specified by the AASHTO code. This report of the Transportation Research Board provides information to assist engineers in implementing the geotechnical features of LRFD methods. Information for the synthesis was collected by surveying United States and Canadian transportation agencies and by conducting a literature search using domestic and international sources. Interviews of selected international experts were also conducted. The limited available experience in the United States and information from international practice are discussed to understand the problems that have arisen so that solutions may be found. Based on a review of various LRFD codes, suggestions for further work are made.