Development and application of a 3D GPU-parallelized CDEM for blasting induced rock fractures

The study has developed a three-dimensional, GPU-parallelized Continuum-Discontinuum Element Method (CDEM) program, utilizing the CUDA C/C++ programming model on GPUs to simulate rock deformation, fracturing, and movement. Initially, the paper outlines the theory and algorithms of the 3D Graphics Processing Units (GPU) - parallelized CDEM, focusing particularly on parallelization and optimization. Performance tests indicate that the 3D GPU-parallelized CDEM achieves a computational speed 645.31 times faster than a single-core serial CDEM code, significantly boosting computational efficiency. The simulation results of rock fracturing were demonstrated through a single-borehole blasting simulation in granite. Material parameters for granite were calibrated using 3D Brazilian and uniaxial compression tests. Comparisons with experimental data demonstrated that the simulation effectively replicated the observed crack patterns. However, discrepancies were noted in stress wave attenuation, and significant errors in crack density were observed across different sections, which may be attributed to variations in loading methods. These comparisons indicate that the proposed model can simulate the entire process of explosive-induced fracturing with substantial improvements in computational efficiency. Nonetheless, further enhancements in accuracy are necessary. These findings underscore the advantages of the 3D GPU-parallelized CDEM in enhancing computational speeds and its potential in geotechnical engineering, especially for simulating rock fractures under quasi-static and explosive dynamic conditions.