Estimation of Cumulative Settlement of Concrete track through the Method Combining Numerical Analysis and Experimental Equation

초록

A concrete track is very susceptible for the settlement, since its rehabilitation requires much time and cost. When a concrete track is constructed on fine-grained subgrade soil, reasonable predictions of excessive cumulative plastic settlements are necessary for the effective track design and maintenance. Generally, elastic settlement can be estimated reliably through numerical analysis. However, there developed no numerical method that can estimate the cumulative plastic settlement practically. Thus the experimental equations which were suggested based on laboratory cyclic loading test and field measurements has been used for the estimation of the long-term cumulative settlement of railway track. The most important factor for the use of the experimental equations is to evaluate the stress state of the subsoil beneath track which directly causes the cumulative plastic strain. In this paper, 3D finite different method was used to evaluate earth pressure distribution beneath concrete track during high speed train passage. Using an existing experimental equation adopting the evaluated earth pressure distribution, the cumulative plastic strain was calculated. The calculated long-term settlements for ten years are presented according to soil conditions. The problems of the existing experimental equation to estimate the cumulative settlement of concrete track are introduced.