Dynamic displacement of sheet pile walls adjacent to the railway track

Due to the scarcity of experimental laboratory research on the effect of repetitive stress resulting from the railway on retaining walls, this study presents an investigation of an experimental laboratory model to study the effect of repetitive loads resulting from the railway on the adjacent retaining wall through several factors. The results of an experimental investigation of horizontal displacements of steel sheet pile walls behind excavations in the sand adjacent to railway tracks are presented. A series of model tests have been carried out in which the effect of sand density, horizontal distance between the railway and the sheet wall, and dynamic load amplitude on the wall horizontal dynamic displacement and its relationship to the railway dynamic vertical settlement were investigated with a load frequency equal to 2 Hz. The study examines various parameters, including different relative densities (30% loose, 55% medium, and 75% dense sand), different distances between the railway and retaining wall (0.5 H, 1 H, and 1.5 H), and variations in burden amplitudes (0.22, 0.44, and 0.66 tons). The most important factor that affects the dynamic displacement ratio (D/H) value is the relative density of the soil. The dynamic displacement ratio inversely correlates with the horizontal distance separating the railway and the retaining wall. The displacement ratio experienced a reduction of approximately 30% and 23% when the railway location relative to the retaining wall shifted from 0.5H to 1H and from 1 H to 1.5 H, respectively. The displacement ratio is directly proportional to the amplitude of cyclic live loading. Ultimately, using dense backfill soil enhances efficiency, resulting in decreased settlement of the railway and improved performance of the nearby retaining walls. It should be noted that there is a direct correlation between the horizontal movement of the wall and the vertical settlement of the rail. In the case of dense soil, these values are closely aligned.