Optimization and Engineering Application of Three-dimensional Multi-pore Groove Structure Based on FEM-SPH Coupling Simulation

To address the issues of insufficient cycle advance and low blast-hole utilization resulting from inappropriate cut blasting layouts during roadway excavation, this study employs the empty-hole effect to establish a three-dimensional cut blasting model using FEM-SPH coupled numerical simulation. The model is used to simulate and analyze the influence of different cut blasting arrangements on rock mass damage, rock throw efficiency, and fragmentation patterns. Furthermore, field engineering tests are conducted to validate the simulation results by examining the residual hole depth after blasting and the cycle advance achieved. The research findings indicate that a cut blasting layout with one central charged hole and five empty holes provides a moderate number of free surfaces, allowing for more sufficient superposition of stress waves and resulting in better blasting performance. Compared to layouts with four or six empty holes, the five-empty-hole configuration demonstrates optimal rock throw effects, with the slot cavity opening size increasing by 67.5% and 46.8%, respectively, and the slot cavity cross-sectional size improving by 99.8% and 1.2%, respectively. Field test results show that the cycle advance achieved with the five-empty-hole layout is 10.2% and 3.2% higher than that of the four-empty-hole and six-empty-hole layouts, respectively. This study provides a theoretical and practical basis for the design and optimization of cut blasting schemes in roadway excavation projects.