Study On Failure Mechanism Of Cement Sandy Gravel Material Based On Particle Flow Code

Cement sandy gravel material is a new type of dam materials,which is to add water,a small amount of gel materials to riverbed sandy gravel or excavation abandoned materials by simple mixing,it has the advantages of economic,safe and convenient construction.Gelation sand gravel materials as a new type of dam materials,not only has extensive application prospect in water conservancy project,its in railway,highway,slope engineering,port and other fields is also relatively favorable application value.Domestic and foreign research achievements of gelation mesoscopic damage of CSG,based on the laboratory experiment and the discrete element particle flow theory,using the orthogonal experiment method to determine the numerical simulation of the mesoscopic parameters influence on macroscopic mechanical behavior,combined with the result of laboratory experiment to conclude the sample of the mesoscopic parameters calibration and the quantitative relation between macroscopic parameters and microscopic parameters,we can observe the specimen with calibration failure process to analyze the stress of CSG materials and the relations between the stress-strain curve and failure process,then further study on the failure mechanism of the material,The research contents of this paper are as follows:1.The stress-strain relationship and ultimate failure mode of cementing gravel materials with different proportions were studied to provide a basis for the numerical simulation of the cementing sand and gravel through laboratory experiments.2.Based on PFC test model,to establish the mesoscopic parameters of gelation sandy gravel material macroscopic mechanical parameters and the influence of the failure mode,and to establish the macro quantitative description method and the parameters of the mesoscopic,laying the ground for calibration mesoscopic parameters;3.The macroscopic parameter calibration results are applied to the numerical model test analysis,and the variation of stress during loading process is studied from the perspective of detail.Sample at the same time,from the perspective of mesoscopicresearch crack initiation,the development and well versed in the process reveal the gelation mesoscopic damage mechanism of sand gravel materials,providing a reference for subsequent gelation of sandy gravel research basis.