Study On The Failure Process Of Sand In Triaxial Test

Digital image messurement mothed was improved in the first part. Improved moving average method was put forward and used in the system to decrease the variance of data fluctuation by50%. Compared with the moving average method, it is more precise and deformation condition of any time can be obtained by the way. Fitting method was used to get more precise axis location. Feasibility that calculate the strain before curve unfolded was proved to remove the truncation error.Then production conditions and formation mechanism of shear band were analyzed by triaxial test based on digital image messurement mothed and finite element simulation with program ABAQUS using Mohr-Coulomb model. The study shows that end restraint and initial weak point are key points which trigger the strain localization. Strain rate of points on the shear band will increase all of a sudden when shear band occurred.