强各向异性岩体开挖弱化机理与强度-刚度主动调控研究

国家基础设施建设至少一半是岩体工程，开挖导致岩体弱化是岩体工程灾害的本质原因。揭示开挖岩体弱化与致灾机理，发展科学、高效、经济的岩体工程灾害防控方法，是保障岩体工程安全的紧迫需求，也是困扰岩体工程学科几十年的难题。本项目将通过岩体强度与刚度各向异性弱化机理的研究，揭示岩体工程灾害诱发模式和围岩大变形与破坏机理，提出岩体工程灾害主动防控方法。.本项目主要研究思路是： ①实施对含裂隙真实岩石和3D打印试件的力学试验，结合数值分析和理论解析，揭示应力-结构控制转化与岩体强度-刚度各向异性弱化机理；②通过成西铁路深埋隧道典型断面的岩体结构、变形与围岩压力断面分布和变化过程的现场观测和理论与数值分析，解析开挖层状岩体的非对称大变形与定向破坏等典型灾害致灾机理；③基于应力-结构控制转化理论，提出以岩体强度-刚度协同调控为基础，既科学、安全，又经济合理的主动防控方法。

Half of infrastructures in our country are rock engineering projects, and excavation induced weakening of rock masses is the essential cause of hazards. It is an urgent and difficult task for the industry and discipline to expose the mechanism of weakening and hazard genesis of rock masses due to excavation, and develop the reasonable, efficient and economic prevention method to ensure the geo-safety of rock engineering. This proposal is to, through the research on the anisotropic weakening mechanism of strength and stiffness of rock masses, reveal the hazard triggering modes and mechanism of large deformation and failure, and propose an active prevention method for the excavation induced hazards..The basic routing of the research is:.① reveal the conversion mechanism of stress-structure dominance and resulting anisotropic strength-stiffness weakening behavior, through mechanical tests on fractured rock samples and 3D printed samples, and their numerical simulation and theoretical analysis. .② analyze the mechanism of typical hazards as asymmetrical large deformation and directional failure in excavated rock masses, through sectional measurements on the structure of rock masses, deformation and rock pressure at deep tunnels in Xi-Cheng railway, as well as their theoretical and numerical analysis..③ establish a scientific, efficient and economic method for active-prevention of rock hazards through the improvement of strength and stiffness of rock masses, based on the conversion theory of stress-structure controlling.