Akademik Veri Yönetim Sistemi
ISRM International Symposium - EUROCK 2020, Trondheim, Virtual, Norveç, 14 - 19 Haziran 2020
© International Society for Rock Mechanics and Rock Engineering Norwegian Group for Rock MechanicsThe mechanical excavation of rocks has been increasing in rock engineering projects. However, the cutting rate is low and the wear of cutting tools is high during the excavation of hard and abrasive rocks. There are some preliminary studies on the microwave assisted hard rock cutting. The objective of these studies is to decrease the rock strength by microwave energy before cutting, and therefore to increase cutting rate and decrease cutter wear. This study investigates the surface temperatures and strength of igneous rocks treated by microwave. First, the uniaxial compressive and the Brazilian tensile strength tests were carried out on the untreated specimens. Then, the microwave treatment was applied on the second group of samples prepared for the strength tests. The microwave powers of 1kW, 2kW, and 6kW were applied at different durations ranging from 60s to 420s. Then, the strength tests were carried out on the microwave treated samples. The mineral contents and percentages of each rock were also determined. The strength values of the granites including a small or significant amount of microwave absorber minerals decrease significantly with increasing surface. The behaviour of the tested syenites and gabbro are different from that of the granites due to their metallic mineral contents or high amount of microwave absorber mineral. It was concluded that the mineral type and percentages significantly influence the heating degree of igneous rocks. The strength of igneous rocks may decrease substantially due to the microwave treatment depending on the applied microwave power and treatment duration. The behaviour of the different igneous rocks having different mineralogy should be further investigated.