膨胀土裂隙再生演化规律与多重裂隙网络模型

Fissure is the control factor inducing expansive soil slope instability, fissures lead to structural damage and strength decay of expansive soil, which affects the long-term security and stability of expansive soil slope. Therefore, research on the regenerative evolution of fissures and multiple fissures network model of expansive soil has important theoretical and engineering significance. The progressive idea will be adopted to explore in the trend of "natural distribution → regenerative evolution → multiple network" of the fissures. Firstly, through the field investigation, the filling characteristics, scale and spatial distribution information of all kinds of fissures of expansive soil slope will be ascertained. Secondly, through experiments, second evolution and propagation law of natural fissures will be revealed, and the correlations between fissure parameters and environmental factors will be established. Thirdly, through theoretical analysis, the fissure regeneration mechanism will be clarified, and the regeneration model of expansive soil under the condition of environment change will be built. Finally, through theoretical modeling, base on the random field theory, combined with statistical simulation technology, a multiple fissures network model of expansive soil slope will be built, to lay the foundation for the research on stability problems of expansive soil slope considering the effects of fissures.

裂隙性是诱发膨胀土边坡失稳的控制性因素，裂隙导致膨胀土结构损伤与强度衰变，影响到膨胀土边坡的长期安全稳定，因此，开展膨胀土裂隙再生演化规律与多重裂隙网络模型的研究具有重要的理论和工程意义。采用探究裂隙“天然分布→再生演化→多重网络”的递进式研究思路，通过现场调研，查明膨胀土边坡各类裂隙的充填、尺度特征及空间分布信息。通过试验研究，揭示膨胀土天然裂隙二次演化过程和传播规律，建立裂隙指标参数与环境条件之间的关联性。通过理论分析，阐明裂隙再生机理，构建外界环境变化条件下膨胀土裂隙再生模型。通过理论建模，以随机场理论，结合统计模拟技术，构建强膨胀土边坡多重裂隙网络模型，为考虑裂隙影响的膨胀土边坡稳定问题的研究奠定基础。

裂隙性是诱发膨胀土边坡失稳的控制性因素，裂隙导致膨胀土结构损伤与强度衰变，影响到膨胀土边坡的长期安全稳定，因此，开展膨胀土裂隙再生演化规律与多重裂隙网络模型的研究具有重要的理论和工程意义。采取地质调研、试验、理论分析与数值模拟相结合的研究方法，通过现场地质调研，揭示膨胀土裂隙地质成因、赋存状态、充填特性，建立了裂隙分级标准，统计获取不同等级天然裂隙的几何特征与空间分布情况。通过膨胀土裂隙二次演化现场试验，以及吸湿与脱湿条件下膨胀岩土裂隙扩展室内试验，进一步揭示了天然裂隙二次演化过程和传播规律，结合数字散斑与图像处理解译技术，对裂隙场信息进行了可视化处理，分析了裂隙位移场与应变场的变化规律。建立了裂隙指标参数与环境因子之间的关联性，构建了外界环境变化条件下膨胀土裂隙再生模型。预测了多重裂隙场分布，建立了含结构性裂隙的膨胀土边坡模型，揭示了结构性裂隙对膨胀土边坡变形的控制作用与致灾机理。将多重裂隙网络纳入膨胀土工程边坡中，分析了裂隙对边坡工程表现的宏观影响。研究有助于对膨胀土地区边坡变形破坏、水土流失问题的理解和认知，为相关工程的膨胀土边坡问题的控制对策及综合治理提供了科学依据。