Study on the Effect of Microwave Irradiation on Rock Strength

Abstract

Microwave-assisted rock breaking can effectively improve rock breaking efficiency, decrease energy consumption, and promote the development of miniaturized and lightweight rock breaking equipment. This study uses rock mass with structural surface as the research object and analyzes the representative volume element of rock mass at varied temperatures. The general expression of rock mass strength is first obtained. The analytical formula of rock mass strength under microwave irradiation is then derived on the basis of temperature rise features under microwave irradiation. The analytical formula is verified by the experiment. Finally, the variation law of rock mass strength is studied. Results show that microwave irradiation effectively decreases rock mass strength. A longer microwave irradiation time corresponds to high microwave power density and low rock mass strength. Rock mass strength decreases linearly when microwave irradiation time and microwave power density increases. The reduction of the rock structural surface is greater than the rock mass strength under the same microwave irradiation.