Influence of toe load on the fatigue resistance of elastic rail clips

Abstract

As a critical component of the fastening system, the elastic rail clip maintains the rail in the vertical, lateral, and longitudinal positions using its specified toe load. In this study, the influence of toe load on the deformation and fatigue resistance of the clip was studied. Finite element analysis, static load experiments, and fatigue experiments were performed to evaluate the deformation and fatigue resistance of the clip. With the contribution of the lateral wheel load, the deformation range of the outer clip was higher than that of the inner clip. Therefore, the cyclic deformation of the outer clip was used for the fatigue experiment. The toe load had no influence on the fatigue resistance of the clip under normal wheel load, i.e. the clips under high, normal, and low toe loads were run-out at 5 × 106 cycles. However, with the contribution of impact on the wheel load, the fatigue lives were reduced to 5468 cycles and 16,839 cycles for the clips under high and normal toe loads, respectively. In the case of low toe load, the clip under the contribution of impact could withstand more than 5 × 106 cycles. Accordingly, the reduction of toe load may enhance the fatigue resistance of the clip under impact.