内外水相互作用下输水隧洞围岩-衬砌联合承载机制与性状演化规律

It is of innovative importance for optimizing national water resources allocation to study the mechanisms of long-distance diversion tunnels. In this project, on the basis of typical water diversion projects across different river basins, laboratory model experiments, discontinuous numerical simulations combined with theoretical analysis will be conducted to study the mutual mechanisms between the inner water, the outer underground water and the tunnel lining structure under different operation conditions. The aging and degradation model of the tunnel and surrounding rock under the inner and outer water pressure, combined with the continuity and non-continuity method, is established to reveal the joint bearing mechanism and character evolution of surrounding rock and lining structure under multi-field coupling effects. This study will serve as the critical theoretical support and scientific decision-making for the design, construction and operation of major long-distance diversion projects in China.

长距离输水隧洞工作机制研究对于实现国家水资源优化配置有重要创新意义。本项目拟以典型跨流域调水工程引水隧洞建设为依托，通过室内模型试验、不连续数值模拟和理论分析等研究手段，揭示隧洞内部输水、围岩外部环境地下水、隧洞衬砌结构及其不同运行工况等因素相互作用机制；建立内外水相互作用下围岩-衬砌结构性能时效劣化模型与连续-非连续力学分析方法；揭示多场耦合作用下输水隧洞围岩-衬砌结构联合承载机理和性状演化规律。可望为我国长距离调水工程等生命线工程的设计、建造及运行提供重要的理论支撑和科学决策依据。

作为长距离调水工程的核心组成部分，输水隧洞是输水建筑物的重要类型。长距离输水隧洞穿越地质条件复杂、沿线埋深差异性大、水力条件内外交互，给隧洞施工及运行安全带来极大挑战。本项目综合采用室内试验、理论分析、数值模拟等多种手段对长距离输水隧洞内外水相互作用机制与结构力学响应、多场耦合作用机制与分析方法、围岩-衬砌结构性状演化规律等问题开展了系统研究，取得的主要成果包括：1）探明了裂隙粗糙性诱发的输水隧洞内-外双向异性渗流特征，揭示了隧洞内部输水、围岩外部环境地下水、隧洞围岩-衬砌结构承载及其不同运行工况等因素相互作用机制；2）建立了复杂地层和荷载作用下输水隧洞结构-应力-渗流演化的连续-非连续分析方法；3）揭示了内外水相互作用下输水围岩-衬砌结构开裂机理和多场耦合作用下的结构性状演化规律。相关成果可为我国长距离输水隧洞的设计、施工及运行提供理论支撑和科学决策依据。