软岩遇水软化的非线性抗剪强度模型

Based on the softening mechanism of the interaction between soft rocks and water, this paper analyzes several factors that influence the softening process, and four variables, clay mineral content, concentration of Ca2+ ,PH value of solution and pore distributed fractal dimension, are chosen as softening factors. Based on analyzing the softening effects of these factors, a dynamical function that describes how the evolvement of the factors leads to the declining of shearing strength is established . According to the ideas of dissipative structure, the effect of softening factors on shearing strength will tend to equalization. Therefore, the concept of effect function is introduced, the parameters of which are got by inversion analysis, and the declining model of shearing strength is presented by Lagrange multiplier method. The model takes the effect of dominating factors on shearing strength into account, and provides the evolvement rule of shearing strength during the saturation period under the circumstance including those factors.