Experimental Research On The Variation Of Impact Resistance Of Rock Caused By Microwave Irradiation

The study of rock-breaking technology is one of the important subjects in geotechnical engineering and mining engineering. In order to solve the problems of rock mechanical drilling and crushing with high speed and efficiency, such as tunnel driving and deep mining,and achieve a new system of "Microwave + Machine" rock breaking as the goal. It is necessary to explore the damage law of impact resistance of rock caused by microwave irradiation. This provides a theoretical basis for the application of microwave-assisted rock mechanical drilling and crushing. The development of microwave-assisted rock mechanical crushing technology, rock crushing theory and rational use have important theoretical and practical significance.By using a combination of theoretical analysis and experimental methods, the variation of rock impact resistance which irradiated by microwave were studied in this paper systematically. By changing the microwave power, rock types, impact load and so on,studying the rock impact resistance damage law after microwave irradiation, and through the rock impact fracture test by SEM after microwave irradiation, we can analyze and prove the reasons for the rock damage. This research analyzes the reason for the change of impact resistance of rock caused by microwave irradiation, rock impact damage characteristics of cracks and the impact fracture process. Specific research contents and results are as follows:(1) By analyzing the response of the rock different minerals which is heated by microwave heating, we can explore the basic principles of rock thermal fracturing and the reason for the variation of impact resistance of rock after microwave irradiation. The factors which affect the rock performance of impact resistance after microwave irradiation include the composition of rock mineral, the type of rock, microwave irradiation parameters, the type of rock structure and loading ways of the impact load and so on.(2)The experiment which is tested for the rock performance of impact resistance after microwave irradiation by using the self-improvement drop impact resistance test device was conducted. During the test, we can get a different case three rock shock resistance weakened condition under certain microwave irradiation power and mutative microwave irradiation time:in 0-10 kW range, the higher microwave irradiation power, the more obvious damage of rock impact resistance after microwave irradiation. And different rocks have different damage degree of rock impact resistance performance under the same test conditions.(3)Carrying on a scanning electron microscope(SEM) test on rock impact fracture by SEM after microwave irradiation. The three rock cracks fracture shape and morphology, the types of micro-cracks and micro-fracture model have been studied on the reason for the change of impact resistance of rock after microwave irradiation from the point of microscopic view and the results have contrast and demonstrate with the drop impact test results theoretical analysis.