Blasting Experiment and Damage Characteristic Analysis of Reef Limestone

ABSTRACT: Reef limestone is a primary focus in island and reef engineering, and studying its damage characteristics under blasting loads is of significant importance. This study conducted blasting experiments using reef limestone replica materials, preliminarily determined model parameters suitable for simulating reef limestone blasting through theoretical derivation, and analyzed the fracture process of reef limestone under different charge configurations and blasting parameters. The research results indicate that compared to terrigenous rocks, reef limestone with lower strength and higher porosity exhibits larger crushing and fracture zones, along with more complex crack development after blasting. When the ratio of borehole spacing to borehole diameter is 13.3 and 20 respectively, the blasting effectiveness and cost of air-coupled and water-coupled blasting in reef limestone reach an optimal balance. Compared to concentric charging configuration, eccentric charging proves more effective in controlling the damage range, providing protection for rocks on the decoupled side, while water as a coupling medium weakens the eccentric effect. The research findings can provide valuable references for the design of blasting in reef limestone.