震区隧道洞口段注浆措施的减震效果数值模拟分析

为研究注浆措施在地震区隧道洞口段的减震效果，基于围岩-结构三维模型，改变注浆的范围及参数，采用有限差分法软件FLAC-3D，分析了某隧道洞口段的动力响应。采用人工拟合地震波、黏性边界条件，输入三个方向的地震波，模拟了原设计、全环间隔注浆措施、局部加强注浆措施三种工况。研究分析了各工况的内力、位移、周边围岩塑性区等，并与全环间隔注浆、局部加强注浆两种减震措施的效果作了对比，得出了地震区隧道洞口段的动力响应规律、减震措施的有效范围及全环间隔注浆措施能起到阻尼减震的效果、局部加强注浆措施能改善衬砌结构内力分布的作用等结论。对高烈度地震区隧道洞口段抗减震措施研究有一定的借鉴意义。

The Numerical Simulation Analysis on the Damping Seismic Effect of Grouting Measures Adopted On the Tunnel Portal Which Located In the Earthquake Regions

In order to study the damping seismic effect of grouting measure on the tunnel portals in seismic regions, based on rock structure 3D model, changed the range and parameter of grouting measure, adopted finite difference software Flac-3D, carried on dynamic response analysis on a tunnel portal section. Used the fitting of artificial seismic waves and viscous boundary conditions, entered seismic wave in three directions, simulated the three conditions of the original design, whole ring interval grouting measure and partial strengthening grouting measure. Researched and analyzed of the conditions of force, displacement, plastic zone surrounding rock, etc. compared the damping seismic effect of whole ring interval grouting measure and partial strengthening grouting measure. It is obtained the dynamic response law of tunnel portals in seismic regions, the effective range of damping measures, and concluded the whole ring interval grouting measure＇s damping effect, partial strengthening grouting measure＇s improving internal force distribution of tunnel linings effect. It also has certain reference significance on the study of seismic shock absorption measures of the tunnel portal which located in the high intensity seismic regions,