Assessment of Design Tools and Criteria for Urban Rail Track Structures. Volume II. At-Grade Slab Track.

摘要

This report presents the results of a critical review of the technical factors which govern the design and performance of at-grade slab track for urban rail systems. The assessment of current design practices is based on a review of the literature and discussions with experienced track design personnel. The evaluation includes descriptions of slab structures now in use in four countries,followed by review of design and analysis procedures used to characterize the subgrade and its support characteristics;the reinforced concrete slab itself,and the subgrade-support system. With a few exceptions,most of the work reported in the literature is based on highway or runway applications,where the mechanism of load transfer into the slab is completely different than in a rail support slab. Further research on the mechanisms of load transfer from rail fasteners into a reinforced concrete slab is needed,and the newly developed finite element approach appears well-suited.