层裂逆向坡地震动力结构响应与灾变机理研究

Being full of understanding slope of dynamic response that is necessary to analyze slope instability mechanism under action of earthquake. It is also the basic to evaluate slope dynamic stability. On the basis of homogeneous slope dynamic response, the investigation on the impact mechanism and characteristics of slope dynamic response due to geological structure is proposed in the project. Guantan landslide is choosed as the prototypes in the project, which is generalized as concepton model on the base of field investigation, experimental tests and mechanism analysis. Using the variables of geometric parameter and physical mechanics parameter, the series of rock slope model with double layer rock stratum and dipping inside structure will be constructed. The dynamic response mechanism of the slope of the assigned geological structure is systematically investigated by the integrated way of seismic model experiment and numerical simulation computer, which can offer the scientific basis for earthquake geology disaster assessment. The geological structure effect of dynamic response is acquired by analyzing the distribution of acceleration, speed and displacement time-travel curves in slope section of different models. Choosing appropriate dependent variable and argument to regression analyze, and conclude the empirical formula that will become engineering geological theory basis for slope stability evaluation and dynamic instability mechanism analysis. The acceleration response characteristics of Guantan landslide is get according to the empirical formula. The Guantan landslope stability is computed by improved limit equilibrium method and the result is contrasted with pre-existing data so that the rationality of the empirical formula is verified.

斜坡地震动力响应规律是分析地震作用下斜坡失稳机理的必要条件，是正确评价斜坡动力稳定性的根本。本项目拟在均质斜坡研究基础上，研究地质结构对岩质斜坡地震动力响应的影响和致灾机理。以罐滩滑坡为原型，在野外调查、试验测试、机制分析基础上构建原型斜坡的概念模型，再以几何参数、物理力学参数为变量，构建系列倾内层裂结构岩质斜坡模型，综合运用超声地震模型试验方法、数值模拟法，研究倾内层裂结构对斜坡动力响应规律的影响和致灾机理，为地震灾区地质灾害评估提供科学依据。分析加速度、速度、位移三量时程曲线分布规律，研究地质结构效应，选择适当的因变量和自变量进行回归分析，建立倾内层裂结构岩质斜坡地震动力响应规律的经验公式，为斜坡动力稳定性评价与失稳机制分析提供工程地质理论基础。将该经验公式应用于罐滩滑坡，得到该滑坡的加速度响应规律，运用改进的极限平衡法，计算其稳定性，对比计算结果与已有资料的差距，验证研究结果的合理性

斜坡地震动力响应规律是分析地震作用下斜坡失稳机理的必要条件，是正确评价斜坡动力稳定性的根本。本项目在均质斜坡研究基础上，研究斜坡结构对岩质斜坡地震动力响应的影响和致灾机理。以罐滩滑坡为原型，在野外调查、试验测试、机制分析基础上构建原型斜坡的概念模型，再以几何参数、物理力学参数为变量，构建系列倾内层裂结构岩质斜坡模型，综合运用超声地震模型试验方法、数值模拟法，研究倾内层裂结构对斜坡动力响应规律的影响和致灾机理，为地震灾区地质灾害评估提供科学依据。本次研究通过物理模型试验、数值模拟反倾内层裂结构岩质边坡的地震响应特征，分析了入射波振幅、频率及坡角、岩层倾角、坡高等对斜坡动力响应特征的影响，充分认识到了层裂反倾内斜坡的地震动力响应特征，并尝试从量化的角度来研究，获得了反倾斜坡在地震作用下易发生破坏的垂直深度范围的简易公式。对灌滩滑坡在地震作用下的致灾机理进行了研究，模拟出了上部受拉，下部受挤压的变形过程，表面斜坡结构和岩体结构是决定该滑坡发展的重要因素。从而在原有的研究计划基础上开展了结构面产状表征、裂隙相交计算等工作，确定了下一步的研究方向。