The Department of Civil and Environmental Engineering is pleased to announce Matthew Millers's MS project presentation: "The Influence of Track-Structure Interaction in the Seismic Analysis of Small to Medium Span LRT Bridges with Continuous Welded Rail."
Date: Friday, February 17, 2012
Location: Engineering Building 310
Adviser: Dr. Peter Dusicka
Summary: The goal of this project was to study the effects of track-structure interaction on the seismic response of small to medium span Light Rail Transit (LRT) bridges. In particular, this project focused on bridges with direct-fixation continuously welded rail (CWR). For LRT bridges with CWR, the rail elements provide an interface that can serve as a means to apply (train braking/traction) longitudinal loads to the substructure or to resist (thermal, seismic) longitudinal loads. The interface between the rail and the structure is referred to as “track-structure interaction”. While track-structure interaction effects are commonly considered for thermal, LRV traction, and LRV braking load cases, guidance on when (or if) and how to consider them in seismic analysis is not as straightforward. In the case of seismic analysis, the resisting effect of the rails can reduce structural deformations and the associated internal force effects of the lateral force resisting members of the structure. Not taking this resisting effect into account during design could lead to the over-estimation of displacements, which could lead to an uneconomical design. By means of a case study, the influence of track-structure interaction was analyzed using elastic dynamic analysis and non-linear time-history seismic analysis methods.