SAFETY OF HIGH SPEED GROUND TRANSPORTATION SYSTEMS. TRACK LATERAL SHIFT: FUNDAMENTALS AND STATE-OF-THE-ART REVIEW

This report presents a review of the state of the art of track lateral shift analysis, with improved concepts for safety evaluation of high speed trains generating track shift forces. The mechanics of track shift and the resulting track failure modes are defined. A critical review of the track shift literature from France, England, Sweden, Japan, and the United States is presented. An approach is suggested in this report for an improved understanding and analysis of track shift for application to the U.S. track conditions. The proposed approach consists of a vehicle dynamic model to predict lateral loads on the track, and a track model to determine limit loads on the track and residual lateral deflections under the influence of the vehicle loads.