基于坡体结构的岩质边坡稳定性分析

STABILITY ANALYSIS OF ROCKY SLOPE BASED ON SLOPE STRUCTURES

充分利用地质资料建立正确的岩质边坡稳定性分析计算模型,对于获得正确的分析结果至关重要。根据地质资料建立坡体结构,由此建立分析计算模型。考虑到岩质边坡所经历的浅表生改造和受到自然营力作用而具有的特殊工程地质性质,坡体结构和现有岩体结构的概念存在较大差别,用这些差别来充实现有坡体结构的概念,由此建立的计算分析模型才能获得较为正确的稳定性分析结果。首先对比坡体结构和岩体结构的不同之处,重点论述建立坡体结构应考虑的问题(即边坡所在岩体的浅表生改造特征)、自然营力对坡体浅层的作用程度和影响范围、坡体地质力学模型涉及的范围等;结合地勘资料建立坡体结构,在此坡体结构上既要能体现边坡所在岩体的地质结构特征,又要能反映其特殊工程地质性,例如组成坡体的岩性、节理裂隙特征、地下水和地表水的作用、结构面形状及其充填物、浅表生改造形迹、风化与卸荷性等;再由坡体结构建立用于稳定性分析的计算模型,确定模型范围、计算参数、主控结构面位置、可能的失稳破坏模式等,在此基础上选用合适的分析理论进行坡体的二维或三维稳定性分析就能得出较为合理的结果。

It is of great importance to obtain the reasonable results of stability analysis of rocky slope by using the engineering geological information to establish the correct calculation model. The model is performed based on the slope structures, which are established from geological information. There are many differences between slope structures and rock masses because rock mass of slope will be encountered with the epigenetic reformation and natural forces. The main difference is that rock mass of slope has the special engineering geological properties, such as traces of epigenetic reformation, the surface weathering, rock mass stress relaxation, erosion of surface water and so on. The rocky slope structure now only contains rock masses and its geological tectonic surfaces, and it will necessarily be enriched by these properties. The reasonable model of stability analysis for rocky slope may be obtained by the slope structure. Rocky slope structures will be first analyzed： and the differences can be obtained. Some key issues for the rocky slope structure, i.e. characteristics of the epigenetic reformation, the action scope of natural factors on slope and the boundary to establish geological mechanical model, are discussed. Many special engineering geological characteristics of slope rock mass, rock-soil slope examples, discontinuities, faults, groundwater, key slide surfaces, calculation parameters and so on can be achieved by the slope structures. The 2D or 3D reasonable results of the stability analysis of slope structures are verified.