浅埋大跨矩形隧道多因素扰动下受力及变形特征研究

Research on Stress and Deformation Characteristics of Shallow-buried Long-span Rectangular Tunnels under Multi-factor Disturbances

摘要:

依托G98环岛高速公路三亚崖州湾科技城隧道工程，通过数值仿真分析方法，研究了浅埋大跨矩形隧道在典型外部多因素扰动作用下隧道结构的受力和变形机制。数值模型考虑了隧道顶部覆土荷载突变、地质软硬互层、后期施工扰动、隧道上部车行荷载等因素；采用弹塑性损伤本构模型模拟混凝土在极端不利荷载作用下的损伤发展过程。基于数值分析结果，系统地分析了隧道结构的应力分布状态、隧道变形模式以及典型外荷载作用下结构损伤演化过程。

Abstract:

Relying on the G98 Ring Expressway Sanya Yazhou Bay Science and Technology City Tunnel Project, by means of numerical simulation, the stress and deformation mechanisms of a shallow-buried long-span rectangular tunnel under the disturbance of multiple typical external factors are studied. The numerical model takes into account the sudden change of overburden load above the tunnel, alternating soft and hard geological layers, as well as potential subsequent construction disturbance and vehicle load on the tunnel roof. An elastoplastic damage constitutive model is adopted to simulate the damage evolution process of concrete under typical extreme adverse loads. Based on the numerical analysis results, the stress distribution, deformation mode and damage evolution process of the tunnel structure under typical external loads are systematically analyzed.