Demand is growing for explosive-free rock breakage systems for civil and mining engineering, and spaceindustry applications. This paper highlights the work being undertaken in the Geomechanics Laboratoryof McGill University to make a real application of microwave-assisted mechanical rock breakage to fullfacetunneling machines and drilling. Comprehensive laboratory tests investigated the effect of microwaveradiation on temperature profiles and strength reduction in hard rocks （norite, granite, and basalt）for a range of exposure times and microwave power levels. The heating rate on the surface of the rockspecimens linearly decreased with distance between the sample and the microwave antenna, regardlessof microwave power level and exposure time. Tensile and uniaxial compressive strengths were reducedwith increasing exposure time and power level. Scanning electron micrographs （SEMs） highlightedfracture development in treated basalt. It was concluded that the microwave power level has a strongpositive influence on the amount of heat damage induced to the rock surface. Numerical simulations ofelectric field intensity and wave propagation conducted with COMSOL Multiphysics software generatedtemperature profiles that were in close agreement with experimental results.
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