为揭示岩溶条件下公路隧道雨后结构病害演化过程，依托京港澳高速大宝山隧道水害案例，通过地质勘察、地表调查与雨后水连通试验，探明水害段地质信息与水力连通特性；基于“无人机航飞+三维地质建模”联合技术，构建考虑地形地貌、隧道结构与地质信息的精细化三维仿真模型，探究强降雨后地层水位骤升时结构受力与变形响应规律。研究结果表明： 1）地层岩溶发育为雨水向下径流提供了良好的水力通道，由此引发的强降雨后地层水位抬升与结构水压骤增是导致结构压溃的直接原因； 2）地形影响下左右线隧道初始应力状态已具有差异性，随着地下水位抬升，结构外水压与内力的不对称式增长使得隧道应力差异性愈发明显； 3）至水位上升60 m时，压应力超限、安全系数过低的结构风险出现于左线高山侧边墙、拱脚处，且与现场病害特征、病害位置吻合良好，验证了模拟方法的可行性与有效性。

To elucidate the reason behind failure of a karst tunnel structure after heavy rainfall, a geological survey, surface investigation, and water connectivity test is conducted for the Dabaoshan tunnel. The geological information and hydraulic connectivity characteristics are analyzed. A combination of an unmanned aerial vehicle flight and threedimensional(3D) geological modeling is introduced to construct a refined 3D simulation model based on topography, tunnel structure, and geological information. Furthermore, the law of structural internal force and deformation response during the sudden rise of the groundwater level after heavy rainfall is investigated. The results reveal the following: (1) The development of karst provides a good hydraulic channel for the downward runoff of rainwater, and the resulting rise in the groundwater level and sudden increase in the external water pressure after the rainstorm is the direct cause of the structural collapse. (2) The initial stress state of the tunnel in the left and right lines is different under the influence of the topography, and with the rise in the ground water level, the asymmetric increase in the external water pressure and internal force makes the difference in the tunnel stress more obvious. (3) The structural risk of overlimited compressive stress and low safety appears at the sidewall and arch foot of the high mountain side of the left tunnel when the groundwater level rises by 60 m, and it coincides with the actual disease characteristics, which verifies the feasibility and effectiveness of the simulation method.