基于矢量分析方法的岩质边坡渐进破坏机理及其稳定性调控

Because it has obvious characteristics of progressive failure and three-dimensional complexity for jointed rock slope, The stability of high rock slope is always the key technical problem for reinforcement and treatment of high rock slope and both reasonable and effective method adjusting to safety requirement is the key to decide whether anti-sliding engineering is safe and economic. Here we focus on progressive failure mechanics and its stability of rock slope. Firstly, according to systemic shear tests and SEM tests with both artificial and natural fissures, the strength-weakening law will be deeply exploded for joints of rock and artificial rock material from both macroscopic and microscopic perspectives. Based on the test results, we can establish the constitutive model considering strength-weakening and dilation properties of structural planes. The tracking model of potential slip surface will be constructed, and the numerical simulation analysis of progressive failure process can be developed, which can explode the progressive failure mechanics of rock slope based on physical model test. Secondly, based on real stress distribution of rock slope during the progressive failure process, the three-dimensional vector sum method can be used to study the stability of rock slope. The failure criteria of potential sliding body can be established on the basis of vector characteristics of sliding force and the indoor model test. Then, the vector analysis method can be put forward for controlling the stability of sliding body. Finally, the research results will be applied in a mine rock slope of Huangmailing located in Hubei province. Based on progressive failure process and slope stability during failure process, the stability of the potential sliding body will be adjusted for safety requirements of mine rock slope. Furthermore, different reinforcement measurements would be reasonably suggested about different regions of sliding body. The research is believed to enrich the theory and application in slope engineering.

节理岩质边坡失稳过程普遍具有渐进性和空间分布复杂性，其稳定性问题是边坡设计和滑坡治理工程中的重点和难点，合理有效的调控方法是决定抗滑工程是否安全经济的关键。本项目围绕岩质边坡渐进破坏机理及稳定性调控方法开展研究。首先，拟通过系统的室内剪切试验和电镜扫描，从宏细观角度揭示结构面强度弱化规律，建立反映结构面强度弱化及剪胀效应的本构模型，构建滑移面潜在路径的追踪模型，形成边坡渐进破坏过程的数值仿真分析方法，结合物理模型试验，研究边坡渐进破坏机理；其次，依据坡体在渐进破坏不同阶段的真实应力分布，采用三维矢量和法，研究其动态稳定性，结合模型试验监测结果，基于力矢量特征，建立潜在滑体失稳判据并提出相应的调控方法；最后，将上述研究成果应用于湖北黄麦岭矿山高边坡工程，研究其渐进破坏过程及动态稳定性，调控潜在滑体稳定性，建议合理的分区加固措施。本项工作可提升边坡渐进破坏及稳定性研究的理论及应用水平。

针对目前我国工程建设中遇到的节理岩质边坡安全这一关键技术难点，本项目开展了岩质边坡渐进性破坏及安全调控研究，研究成果具有重大的理论意义和工程实用价值。本项目基于结构面强度软化和硬化行为，建立了反映节理结构面强度软化和硬化特征的本构模型，在边坡体真实应力状态的基础上提出了基于强度储备概念的边坡矢量和法，并通过边坡体稳定性安全系数和沿滑移面的下滑推力对边坡体进行安全调控，为节理岩质边坡稳定性调控提供一种新的途径和方法。项目主要研究成果如下：（1） 通过将结构面应变软化过程转化为一系列应力跌落与塑性流动过程的方法，拓展至可同时模拟强度软化和硬化行为，建立了对应的结构面本构模型；（2）采用最小势能原理严格推导了求解边坡下滑方向的理论公式，并通过经典算例进行了验证和对比分析，理论上解决了矢量和法中的这个瓶颈问题；（3）针对矢量和法计算结果与规范中坡体稳定状态标准的匹配问题，提出了基于边坡强度折减概念矢量和法，并推导了基于力和力矩矢的安全系数表达式，建立了基于强度储备概念的边坡矢量和法；（4）基于强度储备概念，推导了边坡下滑推力矢量表达式，并提出了边坡下滑推力矢量和法，给出了不同设计安全状态下的下滑推力计算方法，从而可对滑坡体进行安全性调控。（5）基于节理面强度软化本构模型和矢量和法，研究了边坡体的渐进性破坏过程，综合评价了该坡体的稳定性，并提出了对应的安全调控方法。本项目研究成果可为边(滑)坡工程设计及治理提供理论指导和技术支撑。