深埋洞室开挖过程应力瞬态调整诱发的围岩开裂机制

With the construction of large-scale hydropower projects in the southwest moutain areas as the research backgroud,aim at the rock mass excavation of deep buried tunnels and caverns, we will study the process of the dynamic adjustment of secondly stress of surrounding rock mass,establish a 3-D superposition model to simulate the coupled actoin of equivalent blasting load and transinet release of in-situ rock stress.Through analysis of the process of the cracking and propagation of micro-cracks driven by the coupled action of blasting load and transient release of rock stress, reveal the cracking mechanism of surrounding rock mass during process of dynamic adjustment of secondly stress, evaluate quantitatively the influence of additional dynamic stress induced by transient release of in-situ rock mass, propose a macroscopic cracking criterion on basis of peak particle velocity of surrouding rock mass of deep tunnels and caverns that can reflect the influence of amplitude of in-situ stress,provide a theoritical basis for the cracking and deformation control of surrounding rock mass during rock excavation of deep tunnels. The study can help to better understand the formation and evolution mechanism of EDZ (excavation induced damage zone) under high in-situ stress condition,as well as to enrich the cracking analysis theory and calculation method.The research result can find wide application prospects in the fields of water conservancy and hydropower engineering,deep mining and dispose of nuclear waste,etc.

以西南高山峡谷地区大型水电工程建设为背景,针对深埋洞室岩体开挖，研究围岩二次应力动态调整力学过程，建立基于岩石爆破作用应力等效及地应力瞬态释放的三维时空叠加耦合力学模型；通过爆炸荷载和岩体地应力瞬态释放耦合作用下的围岩微裂纹起裂和扩展过程分析，揭示应力场瞬态调整过程深部围岩的开裂机制，定量评价应力场瞬态调整诱发附加动应力对深部围岩开裂过程的影响，提出体现围岩初始应力水平影响、基于质点振动峰值速度的深部围岩开裂宏观判据，为深埋洞室岩体开挖过程围岩开裂及松动变形控制提供理论依据。项目研究有助于加深高地应力条件下围岩开挖扰动区形成与演化动力学机制的认识,丰富深部岩体开裂分析理论和计算方法。项目研究成果在水利水电、深部采矿和核废料深埋处置等领域具有广阔的应用前景。

项目以西南高山峡谷地区大型水电工程建设为背景，针对深埋洞室岩体开挖，研究了围岩二次应力动态调整力学过程，建立了基于岩石爆破作用应力等效及地应力瞬态释放的三维时空叠加耦合力学模型；通过爆炸荷载和岩体地应力瞬态释放耦合作用下的围岩微裂纹起裂和扩展过程分析，揭示了应力场瞬态调整过程深部围岩的开裂机制，并定量评价了应力场瞬态调整诱发附加动应力对深部围岩开裂过程的影响，提出体现围岩初始应力水平影响、基于质点振动峰值速度的深部围岩开裂宏观判据。. 结合项目研究，发表论文17篇，其中SCI收录6篇，EI收录6篇，出版专著1部；授权发明专利6项，培养博士研究生4人，硕士研究生6人。. 项目成果有助于加深高地应力条件下围岩开挖扰动区形成与演化动力学机制的认识，丰富了深部岩体开裂分析理论和计算方法，在水利水电、深部采矿和核废料深埋处置等领域具有推广应用前景。