可溶岩裂隙溶蚀-损伤耦合演化特征及岩溶隧道围岩失稳致灾机制研究

本项目以岩溶隧道运营期间围岩安全性（围岩自身稳定性和支护结构长期可靠性共同作用结果）为研究目标开展系统研究，首先通过一系列试验，揭示可溶岩细观破坏机制和宏观力学特征、可溶岩裂隙溶蚀－损伤耦合演化特征、可溶岩宏观溶解速度与其损伤特性之间的定量关系、岩溶作用下锚杆长期可靠性弱化机制与规律；基于试验结果，建立岩溶作用下可溶岩裂隙损伤模型；基于可溶岩裂隙溶蚀－损伤耦合演化特征，结合岩溶作用下锚杆长期可靠性弱化机制，建立岩溶隧道围岩失稳致灾机制；根据岩溶隧道围岩失稳致灾机制，结合岩溶作用下可溶岩裂隙损伤模型、可溶岩宏观溶解速度与其损伤特性之间的定量关系以及岩溶作用下锚杆长期可靠性弱化规律，建立定量与定性相结合的可考虑岩溶作用对锚杆长期可靠性弱化影响的岩溶隧道运营期间围岩长期安全性趋势预测方法，并进行实际工程分析。该研究成果可为我国岩溶地区隧道工程的设计施工及安全运营提供重要的理论和技术支持。

Aiming at safety of surrounding rock during the operation of Karst tunnel which combined with the stability of surrounding rock and long-term reliability of supporting structure, the system research on this project has been done. At first, through a series of tests such as meso-mechanics test, triaxial compression test, creep test, coupled mechanics-penetration-dissolution test of Karst rock cracks, Karst rock damage characteristics test with dissolving effect and bolt long-term reliability simulation test with dissolving effect, meso-destruction mechanism and macro-mechanical characteristics of Karst rock, coupled dissolved-damage characteristics of Karst rock cracks, the quantitative relationship between macro-dissolving speed and damage characteristics, and the machanism and weaken law of bolt long-term reliability with dissolving effect have been obtained. Based on the result of Karst rock mechanical test and coupled mechanics-penetration-dissolution test of Karst rock cracks, damage model of Karst rock crack with dissolving effect has been built. And then, based on coupled dissolved-damage characteristics of Karst rock cracks and the machanism of bolt long-term reliability with dissolving effect, mechanism of instability of surrounding rock of Karst tunnel has been obtained. At last, associated with mechanism of instability of surrounding rock of Karst tunnel and damage model of Karst rock crack with dissolving effect and the quantitative relationship between macro-dissolving speed and damage characteristics and the weaken law of bolt long-term reliability with dissolving effect, combined qualitative and quantitative method for the forecast on long-term safety trend of surrounding rock with the influence for bolt long-term reliability by dissolving effect during the operation of Karst tunnel has been obtained and applied into the actual tunnel engineering. The achieved results can provide the important theoretical and technical support for design and construction and safe operation of tunnel engineering in Karst area of China.