【摘要】 为了深入揭示逆冲断层在沉积层中的破裂规律,采用相似材料模拟试验和数值模拟相结合的方法,利用投影条纹法测量模型表面位移,利用ANSYS软件模拟了不同的基岩断层倾角θ和沉积层厚度δ条件下逆冲断层在沉积层中的破裂演化过程。相似试验和数值模拟结果表明:(1)基岩中逆断层的活动沿着逆断层倾角θ向沉积层内扩展,且基岩上盘破坏较下盘剧烈,断层间以挤压作用为主,θ和δ是影响逆断层破裂扩展的重要因素;(2)θ在一定范围内,且在相同沉积层厚度δ和外载条件下,θ增加使逆断层逐渐发育至沉积层表面,并在表面形成:宽度逐渐减小的变形带,宽度逐渐增大的等效应力带,表现为离面位移逐渐增大,沉积层的变形破坏更剧烈;(3)δ在一定范围内,且在相同θ和外载条件下,δ增加使沉积层的变形位移在垂向上降低并转为横向传递,且横向影响范围逐渐增大,逆冲断层破裂存在三种扩展形式。数值模拟结果与相似试验结果具有较好的一致性,研究结果为确定逆冲断层发震产生的变形和破坏提供了基本依据。更多还原

【Abstract】 Using similar material experiment and numerical simulation,thrust fault rupture features were researched in sedimentary rock.The model surface displacements were measured on the basis of fringe projection technique.And thrust fault models with different fault-dip θ and sedimentary thickness δ were simulated by ANSYS software.Conclusions are as follows:(1) thrust fault activities expand to sedimentary rock along fault-dip direction.Damage caused by compression is the main effect,and θ and δ are the main factors in bedrock hanging wall;(2) under the same δ and load condition,deformation and equivalent stress zones appear on the sedimentary surface as θ increases,but deformation zones decrease.The equivalent stress zones and out-of-plane displacement are increased,the damage is serious;(3) Under the same θ and load condition,as δ increases,the deformation in sedimentary rock reduces in vertical direction and is transferred to horizontal direction,the influence range in horizontal direction increases gradually.The sedimentary rock’s deformation is divided into three forms.In conclusion,the simulation results accord with the experiment results,which provide a theoretical basis for estimating the earthquake damage caused by thrust fault.更多还原