Experimental analysis of a high-speed-railway embankment intersecting steep ground fissures at different angles

A high-speed-railway (HSR) embankment intersection with ground fissures is a commonly encountered engineering problem. This paper reports a series of experiments conducted on a reduced scale to investigate the influence of different ground-fissure intersection angles on a HSR embankment. The tests revealed the presence of an integrated bend-tension failure mode in the embankment's reinforced concrete (RC) slab as a result of activities associated with ground fissures. The results showed that the length and the area of the RC slab failure zone decreased nonlinearly with an increasing intersection angle, while the pile load and pile end-bearing varied to different extents in the foundations as they were affected by the slab deformation and rotation. Although the smallest effect on the embankment was observed when the ground fissure intersected the HSR orthogonally, traditional designs that incorporated this do not meet the minimum safety standards. The results of this study show that train-load-induced embankment settlement is insignificant compared with that induced by ground fissures. Therefore, this effect should be given priority in the design of alternative HSR embankments, especially for those in fissure-prone areas.