CAI Qi-peng, NG C W W, HU Ping, et al. Effects of pre-existing fracture on propagation of normal fault ruptures in layered cemented soil[J]. 2017, 38(7): 2015-2021.
CAI Qi-peng, NG C W W, HU Ping, et al. Effects of pre-existing fracture on propagation of normal fault ruptures in layered cemented soil[J]. 2017, 38(7): 2015-2021.DOI: 10.16285/j.rsm.2017.07.022.
It is known that bedrock fault movement can cause the deformation of overlying soil during an earthquake. However
the mechanisms of fault propagation in layered cemented soil and the influences of pre-existing fracture on soil have not yet been fully understood. In this study
four centrifuge tests were conducted on 9-layered soil of clay and sand to investigate the effects of cementation and tip depth of pre-existing fracture. Centrifuge testing results show that the layered uncemented soil was subjected to deform by the shear force after normal faulting. Then
an upside down trapezoidal distribution of uneven settlement area was formed
and a shearing localization zone was also developed above the bedrock fault. When the uneven settlement finally reached the ground surface
tensile ruptures were formed at the top of the unsaturated clay layer. The bending deformation found in the layered cemented soil induced the shearing and tensile ruptures. The depth of surface fault ruptures in cemented soil was greater than that observed in the uncemented soil. In layered cemented soil
with increasing the tip depth of pre-existing fracture
the dip angle of the rupture initiating from the tip of the pre-existing fracture increased
and the surface fault rupture moved towards the hanging wall.