Assessment of Sleeper Stability in Ballast Bed Using Micro-tremor Sampling Method

Abstract

The quality of sleeper support plays an important role in static and dynamic behavior of ballasted track. Sleepers in track should be well supported in vertical, lateral and longitudinal direction. Irregular vertical support (along zaxis) leads to significant increase in dynamic forces in the wheel-rail contact (increase up to 80% comparing to the sections with regular sleeper support). Irregular lateral support (along y-axis) reduces track lateral stability and increases the susceptibility to track buckling. Longitudinal support (along xaxis) is important for the behavior of the continuously welded rails. In the previous research conducted by the authors, application of micro-tremor analysis for determination of vertical sleeper support was considered. This paper investigates its further application for assessment of sleeper support in lateral and longitudinal direction. The obtained results are presented and discussed.