Quasi-Static and Dynamic Tensile Behavior of Water-Bearing Sandstone Subjected to Microwave Irradiation

Microwave irradiation on rocks before excavation is an effective method to reduce equipment wear and energy consumption during mechanical cutting. Rock mass usually carried out in a water-rich environment exposed dynamic loads, thus understanding the coupled effects of water content loading rate behavior under microwave radiation essential. In this study, sandstone samples with five levels (from oven-dried water-saturated) were at power 700 W for 10 min. Brazilian disc tests conducted after both quasi-static conditions. Test results revealed that, increase initial content, heating capacity rock significantly improved. The surface temperature saturated approximately 1.38 times higher than that dry ones. Moreover, weight, P-wave velocity, tensile strength decrease, while porosity damage factor exhibit similar growth law. Before irradiation, average value velocity about 2521.3 m·s−1 4.65 MPa. However, treatment, when was 2%, 3%, 4% 5.4%, decreased by 6.1%, 9.8%, 16.4% 30.2%, reduced 9.2%, 16.7%, 30.6% 48.9%, respectively. For water-saturated increases from 13.02% 18.12% (showing 39.2%), rises 0.51. addition, shows significant dependence, as increases, also (DIF) increases. At given rate, dissipation decreases which indicates presence cause more subjected radiation. Scanning electron microscopy (SEM) indicate internal dominated intergranular cracks, crack density increasing samples. underlying mechanisms water-bearing interpreted theory pore pressure structural thermal stresses.