基于主动-释能理念的隧道岩爆防治机理及其支护技术研究

Start with the analysis of the action mechanism and existing problems of passive supporting system used in current rock burst prevention. The relationships among the occurrence of rock burst and the evolution characteristics of the stress field and elastic strain energy of the surrounding rock are then analyzed. Based on the concept of active-changing the stress condition of surrounding rock quickly after tunnel construction and release elastic strain energy to some extent, researches are carried out on the active-energy absorbing anchorage component of the primary support and its mechanical properties. Thus, the mechanical properties of the supporting components in the active-energy absorbing supporting system and the mechanism of coordination between the rock burst prevention of new type rock bolt are analyzed systematically, forming the supporting system of rock burst prevention whose main body is “active-energy absorbing rock bolt”. On the basis of this supporting system, the prevention and control mechanism are analyzed for rock burst prevention system whose main idea is active-energy absorbing concept, revealing the suppress effect of active-energy absorbing supporting system on rock burst under different parameters. Eventually, the prevention principle and design parameters of active-energy absorbing supporting system under different levels of rock burst are put forward and the design theory and method of the supporting system in tunnels with rock burst based on the idea of active-energy absorbing concept are built.

从当前岩爆防治过程中被动支护体系的作用机理及存在的问题分析入手，通过剖析岩爆发生过程与围岩应力场及弹性应变能演变特征间的相互关系，以隧道开挖后能快速主动改变围岩应力状态及适当释放围岩弹性应变能为设计理念，开展初期支护中主动-释能型锚固构件的研发及其力学性能的测试，系统研究主动-释能支护体系中各支护构件的力学特性及其与新型锚杆间防岩爆协调作用机制，形成以“主动-释能锚杆”为主体的隧道防岩爆支护系统。以该支护系统为基础，剖析以主动-释能为核心思想的岩爆支护作用机理，揭示不同参数条件下主动-释能型支护体系对岩爆的抑制效果，提出不同岩爆烈度等级条件下主动-释能支护体系的防治原则及设计参数，建立岩爆隧道中基于主动-释能理念的支护设计理论与方法。

以近年来我国西部地区交通基础设施建设过程中大量出现的岩爆隧道为工程背景，以提出的主动-释能支护理念为核心，采用资料调研、室内试验、现场测试、理论分析与数值分析相结合的综合研究手段，基于所研发的主动-释能型锚固构件，对主动-释能支护体系中各支护构件的力学特性、防岩爆协同作用机制、岩爆支护作用机理、主动-释能型支护体系中的关键设计参数等重要技术问题开展系统深入研究，取得了以下主要研究成果：.1）揭示了现行岩爆隧道中支护体系被动防护的特点，结合传统防岩爆支护体系效果不佳的分析，提出了主动-释能防岩爆支护理念；.2）揭示了预应力主动-释能支护防岩爆机制及对岩爆的抑制效应，验证了岩爆隧道中采用预应力-释能锚固系统为核心的主动-释能型结构体系的可靠性；.3）研发了一种集“主动与释能”、“临时与永久”等支护功能于一体的新型预应力让压锚固系统，揭示了其全过程力学特性与横阻支护的可靠性；.4）探明了垫板、球垫等组件在预应力锚固系统中的协同作用性，揭示了预应力锚固系统中垫板、球垫与杆体间的力学特性关系,构建了垫板、球垫等支护构件最佳协同受力的主动-释能型锚固系统；.5）探明了各岩爆等级下不同预应力锚杆参数（预应力大小、间距、长度等）对岩爆的控制效果，揭示了超前预应力锚杆联合传统径向预应力锚杆联合支护体系的防岩爆优越性，形成了“中等以下消除、强烈以上降低”为主导思想的岩爆主动-释能支护体系设计原则与方法，建立了与烈度等级相适应以新型预应力让压锚固系统为载体的主动-释能防岩爆支护体系。