Research On Progressive Fracture Of Anti-dip Layered Rock Mass Based On DDA

The study shows that the most typical deformation and failure mode of the anti-dip layered rock slope is the dumping deformation,and the landslide or collapse formed by the deformation and damage often causes major property losses and even casualties.Therefore,correct,qualitative and quantitative understanding of the dumping failure process and characteristics of the anti-dip layered rock slope can provide a correct and effective reference for the later specific slope engineering treatment.For this reason,based on the rock failure mechanism and mechanics principle,four basic mechanical models of superimposed cantilever beam,independent cantilever beam,superimposed simply supported beam and independent simply supported beam are used to analyze the rock mass of anti-dip rock slope.According to the characteristics of stress,the stress calculation formulas of four kinds of mechanical models are given,and the mechanical criterion of tensile failure deformation under four models is given.The calculation formulas and fracture characteristics of rock fracture location in four mechanical models are analyzed.Relying on the ideas of various finite element and discrete element meshes,according to the good applicability and effectiveness of discontinuous deformation analysis(DDA)in rock mass analysis applications,comprehensive consideration of computational efficiency and practicability,in computer programs The DDA analysis algorithm of cantilever beam and simply supported beam is realized.The"artificial joint plane"is used to cut the rock mass,and the"artificial joint"is converted to"real joint".The fracture of the unit block in DDA is preliminarily realized.Further,using the improved DDA program,the causes of the"zonation"in the deformation and failure process of the 4~#dumping body in the left bank dam,Ciha Gorge,are analyzed in detail,and the tensile cracks in the rock mass dumping failure process are generally presented as"upper and lower".At the same time of the small cause,it explains the reason why the special tensile cracks appear to be"big top and small bottom".In the process of analyzing the"zonation"in the deformation and failure process of the dumping body,the gradual and cumulative characteristics of the anti-dip layered rock slope are summarized.Finally,through the comparison of the site survey results and the simulation results,the applicability and effectiveness of the DDA analysis method coupling cantilever beam and simply supported beam in the application of dumping deformation and failure of anti-dip layered rock slope are verified.