Research On Macroscopic Peak Intensity Prediction Method Of Muddy Interlayer Based On Finite Element Calculation Of Meso-mechanics

Clay interlayer is one of the common soft interlayer in the bedding slope, its physical and mechanical performance affects the overall stability of the slope greatly. However, due to the origin and surroundings, its performance index is generally far less than the overall performance of the slope body, therefore, the strength of the clay interlayer is one of the important factors which affects the stability of slope. However, the macro intensity of Clay interlayer is chained down to its micro structure and defect, therefore, using the continuum mechanics to analyze its strength and stress strain response can't reflect the infulence of the overall stability caused by Micro view parameters. In view of this, considering the perspective of the mesoscopic scale and the mesoscopic structure characteristics of clay interlayer, regarding the clay interlayer as pore- matrix composite materials and integrating abnormal laboratory test, using the finite element calculation of mesoscopic mechanics analysis of the macro response of the mesoscopic parameters, we can predict the strength of Clay interlayer, the main research content includes the following aspects:(l)Obtaining mesoscopic structure characteristics of Clay interlayer by SEM, using the image processing software MATLAB and WINTOPO to divide clay matrix body-gap; extracting porosity matrix and vector boundary, and converting it to editable digital image.(2)Analyzing the mesoscopic fabric image of clay interlayer, considering mesoscopic gap's size and distribution, combining with the mesoscopic mechanics of composite materials, the basic hypothesis of inclusion body can classify clay interlayer mesoscopic structure and simplify it too, so it will become a kind of suitable for numerical modeling of the image.(3)Through the indoor uniaxial compression test to gain modulus of clay interlayer, at the same time, using the white light three-dimensional strain measurement technique to get strain development of clay layer under the action of external force, determine the fracture strain values.And then through the mesoscopic mechanics M-T method and mixed law to analyze effective modulus and poisson's ratio of clay matrix of clay interlayer.(4)Utilizing finite element software ANSYS to establish the mesoscopic scale mud layer numerical model to analyze the infulence to clay interlayer internal stress distribution situation and gap of the ultimate bearing capacity of clay layer under the condition of elastic strain limit. Through numerical model to simulate the indoor uniaxial compression under the action of the strain development of mud layer, combining with the definition of the strain failure criteria to determine the peak strength of clay interlayer..In this paper, considering the clay interlayer mesoscopic fabric characteristics, using the mesoscopic mechanics theory, integrating the indoor experiment and finite element method, and the aim is to explore a path to analyze the peak intensity of clay interlayer in the field of mesoscopic:Synthesis parameters (E, v) access-matrix body parameters (E, v) reverse analysis and mesoscopic fabric equivalent simplification-strain failure criteria-determine the peak intensity.So, in this way we can use clay interlayer continuum mechanics to analyze clay interlayer and we can consider the influence of its internal micro information.