地震动荷载下深埋巷道压力拱高度响应规律的数值模拟研究

为了揭示深埋直墙拱形巷道压力拱高度在单向水平地震动荷载下的响应规律，基于FLAC^3D数值模拟和经典弹塑性理论，研究了围岩级别、巷道埋深、地震动荷载强度和地震动荷载作用时间对拱顶竖直方向上的围岩压力拱高度的影响规律。根据数值模拟结论，建立围岩压力拱的多元回归预测模型，并通过对比分析验证了结论的正确性。建立了压力拱高度与围岩级别、巷道埋深、地震动荷载强度和地震动荷载作用时间的相应关系式。研究结果表明，各因素影响程度大小排序为：围岩等级>动荷载强度>动荷载作用时间>巷道埋深。研究成果可为深埋巷道施工和抗震支护设计提供一定的指导。

Numerical Simulation Study on the Response Law of Pressure Arch Height of Deep-buried Tunnel Under Seismic Dynamic Load

With the increasing number of underground roadways built in high-intensity earthquake zones in western China，and ground motion loads will cause various earthquake damages in the roadways，this has aroused the attention of the academic community to the seismic resistance of the roadways，but there are few pressure arches in the academic community.The dynamic load response law of high altitude and its influencing factors were analyzed.Therefore，this paper studied the change law of pressure arch height under seismic dynamic load for deep horseshoe-shaped roadways.Taking the flood drainage roadway of Xiaomaliu tailing reservoir in Xichang，Sichuan Province as an example，based on \mathrm{F}\mathrm{L}\mathrm{A}{\mathrm{C}}^{\mathrm{3}\mathrm{D}} numerical simulation orthogonal test，classic elastoplastic theory and pressure arch theory，this paper studied the influence law of the surrounding rock level，the buried depth of the roadway，the strength of the ground motion load，and the action time of the ground motion load，on the pressure arch height of surrounding rock in the vertical direction of the vault.Based on the conclusions of numerical simulation，a multiple regression prediction model of surrounding rock pressure arch and a time series prediction model of pressure arch height were established.The correlation degree of each influencing factor was studied through the correlation analysis of various factors，and the correctness of the conclusion was verified through comparative analysis.Based on this，corresponding relations between pressure arch height and surrounding rock level，roadway buried depth，ground motion load intensity，and ground motion load action time have been established，and the time effect of earthquake was considered in this paper，and the time correction of the regression model was proposed，which is more suitable for pressure arch height prediction under actual conditions.Some research results were obtained：Pressure arch height H and surface dynamic load amplitude A，dynamic load action time t，roadway buried depth h and surrounding rock grade SRC is positively correlated.And according to the analysis of MATLAB correlation degree，the order of the degree of influence of each factor is：Surrounding rock grade>dynamic load strength>dynamic load action time>roadway buried depth.Advance grouting support should be considered during construction to maintain the stability of the pressure arch.The seismic resistance of the weak surrounding rock should be considered to increase the support strength，and the pre-reinforcement treatment should be performed on the top of the roadway.The research results of the thesis have certain reference significance for the construction and support design of deep buried roadways.