穿越走滑断层隧道错动影响分区及隧道节段式衬砌抗错断性能控制

为了揭示我国西部地区穿越活动断裂公路隧道工程的变形及力学特性，通过数值模拟分析了断层左旋走滑运动对隧道结构产生的错动响应，建立隧道受断层错动影响分区，并提出隧道节段衬砌铰接设计这一抗错断措施。通过对比在影响区内设置不同长度节段衬砌时隧道结构的应力、位移响应规律，得出最优衬砌节段布置形式。研究结果表明：断层走滑错动2.5m时，隧道结构受错影响范围为断层与活动盘交界面附近2.7d(d为隧道跨径)内，定义1d~2.7d范围内为次要影响区，1d范围内为主要影响区；通过对比分析发现3 m节段对衬砌结构水平位移和最大剪应力的控制效果最好，峰值最大降低率分别达到了3.38%和43.34%；隧道结构在断层交界面附近水平位移达到最大，随后向两侧较远位置变形不断减小至平稳；可见隧道结构沿纵向所受的最大剪应力值集中在错动影响区内，且在此范围内变化相较此范围外更加剧烈，错动影响区是抗断层错动设防重点关注对象。研究结果可为隧道抗错断设计提供参考。

Study on the misalignment influence zone and the misalignment resistance of segmental lining of tunnel through strike-slip faults

In order to reveal the deformation and mechanical properties of highway tunnels crossing active faults in the western region of China, the misalignment response of the tunnel structure under the left-turn slip fault are analyzed by numerical simulation, the zoning of the tunnel affected by the fault slip is established, and the articulated design of the tunnel section lining is proposed as a measure to resist the fault slip. By comparing the stress and displacement response of the tunnel structure when different lengths of segmental lining are set up in the affected area, the optimal lining segmental arrangement is derived. The results of the study show that: when the fault slips 2.5m, the tunnel structure is affected by the fault within 2.7d (d is the diameter of the tunnel) near the interface between the fault and the active disk, defining 1d~2.7d as the secondary impact area, and 1d as the main impact area; through comparative analysis, it is found that the 3 m section has the best control effect on the horizontal displacement and maximum shear stress of the lining structure, and the maximum reduction rate of the peak reaches 3.38% and The maximum shear stress along the longitudinal direction of the tunnel structure is concentrated in the misalignment zone, and the changes in this range are more dramatic than those outside this range, so the misalignment zone is the key target of anti-fault misalignment prevention. The results of the study can provide a reference for the design of the tunnel against fault.