论文部分内容阅读
基岩断层错动引起上覆土体变形,互层胶结土体中断层破裂机制认识不足,隐伏裂缝影响规律掌握不明确。基于4个离心机试验,针对黏土与砂土构成的9层互层土,对比土体胶结特性和隐伏裂缝上断点埋深影响。试验结果表明,正断层错动影响下,互层非胶结土体受剪切作用发生变形破坏,在断层上方形成一倒梯形分布的不均匀沉降区,并形成集中剪切带。当不均匀沉降传至地表时,顶层非饱和黏土层形成地表张拉破裂。而互层胶结土则观测到受弯变形破坏,从而产生剪切破裂和张拉破裂。其中,地表张拉破裂的深度远大于互层非胶结土体的观测结果。互层胶结土中,随着隐伏裂缝上断点埋深的增加,由上断点扩展形成破裂的倾角随之增加,地表破裂向上盘一侧偏移。
The deformation of bedrock faults caused the deformation of overlying soils, the lack of understanding of the fault rupture mechanism in interbedded cemented soils and the unclear influence of hidden cracks. Based on four centrifuge tests, the effect of clay interbedded with sand on the interbedded layers of soil was compared with that of the soil and the buried depth of breakpoint on the hidden cracks. The experimental results show that under the influence of the normal fault, the non-cemented soil in the interbedded layers deforms and breaks under the shearing action, and a non-uniform sedimentary zone with inverted trapezoidal distribution forms above the fault and forms a concentrated shear zone. When the uneven subsidence spread to the surface, the top layer of unsaturated clay surface tension rupture. The interbedded cemented soil is observed bending deformation damage, resulting in shear failure and tension rupture. Among them, the depth of surface tension failure is much larger than that of the non-cemented soil. In the interbedded cemented soil, with the increase of the buried depth of the breakpoint on the hidden fracture, the dip of the rupture formed by the extension of the upper breakpoint increases, and the surface rupture shifts to the upper plate side.