Taiwan High Speed Rail Track-Structure Interaction

Track-Structure Interaction Analysis

SC Solutions was commissioned by Mott MacDonald to conduct the seismic track-structure interaction analysis of standard elevated viaducts in support of preliminary design efforts for the Taiwan High Speed Rail Project.  The Taiwan High Speed Rail Consortium is responsible for the design and operation of the 340-km long high-speed rail line, which serves the densely populated western side of Taiwan Island between the major cities of Taipei and Kaoshiung at a maximum speed of 350 km/hour. 

To ensure safe operation at the maximum speed during moderate earthquakes, track deformation must be below specified values when the structures are subjected to dead load, temperature variation, train braking load and earthquake excitation.  Since the highly non-linear ballast behavior is a function of both vertical load and loading history, a series of non-linear 3D finite element analyses were performed simulating the loading and construction sequences.

Multiple input time histories were generated at support locations to match design spectra and statistical spatial coherency functions caused by complex wave propagation mechanisms such as wave passage, scattering and attenuation effects.  Two viaduct configurations were studied to evaluate the effect of pier height variation on seismic responses.  For each configuration, a 750m long 25-span segment was modeled,  able to accommodate the 300m long train sufficiently far from the boundaries of the model to make the boundary effects negligible.  The analysis also employed contact surfaces to simulate the PTFE bearings at each end of the box girders in addition to the non-linear plastic ballast model.