Macro And Micro Numerical Simulation Of Deformation And Fracture Of PBX

In this paper, extended finite element method(XFEM) was used to simulate the deformation and failure process of polymer-bonded explosives(PBX) under the static and dynamic loading conditions at macro and macro–micro multiscale level.The deformation, damage and failure process of Brazilians Test under static loading at macro level were simulated by XFEM, the calculation results were in good agreement with experimental results. Moreover, the calculation models of three improved Brazilian tests were built and simulated, and the effect of difference loading forms on mechanical response, deformation and fracture have been analyzed. The result shows that the contract stress can be reduced in these three improved Brazilian Tests. A semi-circular plate bending model, a uniaxial compression block with a central ramp crack model and a disk with a hole model were established to simulate under static loading, the crack propagation path and failure mode agree well with the experiments.The Brazilian Test model under dynamic loading was built and simulated to obtain stress field, strain field and crack propagation path. The effect of different loading speed on compression load history and crack initiation time was studied.A micro-model was established by using Matlab process, and then two macro-micro model of three-point bending and semi-circular bending were established combined with bonding-node method and common-node method in Abaqus. The loading force- loading displacement curve and loading force- crack opening displacement curve were obtained. the critical opening displacement of two different microscopic models was also predicted.