缓倾层状软弱围岩隧道底部变形极易导致轨道不平顺、结构破损病害等问题，且隧底变形发展持续时间长，严重影响高速铁路运营安全与运输秩序。缓倾层状围岩构造力学特征与赋存环境复杂多变，围岩-隧（仰拱及填充）-轨（无砟轨道）多刚度结构体系协调变形机理不明，缺乏针对性防控措施。本项目拟通过岩石动-静组合加载试验、3D打印模型试验、数值仿真等手段，探明缓倾层状围岩各向异性力学行为及变形特征，揭示缓倾层状软弱围岩隧底变形与破坏机理，建立围岩-隧-轨多刚度体系协调变形作用分析模型，厘清隧道轨下多层结构界面力学响应规律，构建基于高速列车行车安全的隧道轨下变形预警系统，发展缓倾层状软弱围岩隧底变形防控理论与设计方法，开发适用于高铁隧道时空受限条件下的快速、无干扰隧底强化与变形控制新工艺、新材料。为缓倾层状软弱围岩地段新建高铁隧道的合理设计以及既有隧道的科学维养提供理论依据和技术支撑。

In the soft surrounding rock with gently dipping layers, the deformation at the bottom of the tunnel can easily lead to track irregularity, structural damage and other problems, and the deformation at the bottom of the tunnel lasts for a long time, which seriously affects the operation safety and transport capacity of high-speed railway. The structural mechanics characteristics and geological environment of gently dipping layered surrounding rock are complex. The coordinated deformation mechanism of multi-rigidity structure system of surrounding rock-tunnel (inverted arch and filling) -track (ballastless track) is unclear, and there is a lack of pertinent prevention and control measures. This project intends to explore the anisotropic mechanical behavior and deformation characteristics of gently dipping layered surrounding rock by means of rock dynamic-static combined loading test, 3D printing model test and numerical simulation, and reveal the deformation and failure mechanism of tunnel bottom in gently dipping layered soft surrounding rock. At the same time, the analysis model of coordinated deformation of multi-stiffness system of surrounding rock-tunnel-rail is established, the mechanical response law of multi-layer structure interface under tunnel track is clarified, and the early warning system of deformation under tunnel track based on the safety of high-speed train operation is constructed. In addition, the theory and design method of deformation prevention and control of tunnel bottom in gently inclined layered soft surrounding rock are developed, and new technologies and materials for rapid and non-interference reinforcement and deformation control of high-speed railway tunnels under time and space constraints are developed. It provides theoretical basis and technical support for the rational design of new high-speed railway tunnels in gently inclined layered soft surrounding rock areas and the scientific maintenance of existing tunnels.