Numerical investigation of the effectiveness of a step-shaped trench in reducing train-induced vibrations

In this paper, a step-shaped trench was introduced for the attenuation of train-induced vibration levels on trackside buildings. In order to evaluate the effectiveness of the proposed type of trench in comparison with a standard rectangular trench, a two-dimensional finite element model was developed under plane strain conditions using the ABAQUS software. The validity of the preliminary model of the track including a rectangular-shaped trench was confirmed by a close agreement of obtained results with those of previous studies. The effectiveness of the step-shaped trench compared with the rectangular type was studied in open and in-filled forms in terms of decreasing the effects of ground-borne vibrations on trackside structures. The obtained results for open and in-filled step-shaped trenches respectively showed 21% and 26.2% decreases in the maximum amplitude reduction ratio with respect to the common rectangular trench. Moreover, in the case of a real train moving loads, the proposed trench shape further decreased the values of peak particle velocity, root mean square and particle velocity decibel on a trackside structure compared with the values obtained for a rectangular-shaped trench.