ABSTRACT
Although use of non-ballasted continuous welded rail (CWR) has become inseparable portion of light-rail transit (LRT) projects due to maintainability, safety, and passenger comfort, the CWR could adversely affect the bridges supporting the LRT vehicles through rail-structure interaction (RSI). Due to temperature variations, significant axial rail stresses/deformation may develop affecting the track serviceability by increasing the probability of rail fracture. Additionally, the substructure forces caused by the RSI effects are not addressed by the current design codes, resulting in inaccurate estimation of these. These effects are aggravated by using long multi-frame multi-span bridges with curved alignments. In this paper, a nonlinear RSI analysis was undertaken for five long curved bridges with a combined length of more than 2.5 mi (4.02 km) to accurately compute rail stresses, rail gap, and substructure forces. As a result, modifications to the existing simplified approaches are proposed to improve the estimate of the RSI effects.
