Abstract:

Uniaxial compression test and triaxial compression test in different confining pressures were carried out by rock mechanics testing system RMT-150B for rock samples from hard rock roadway in Wolonghu mine. The tests showed that rock specimens presented a tensile failure in uniaxial compression test and a compression-shear failure in triaxial compression test. And in triaxial compression test, both compressive strength of rock specimens and elastic modulus increased with confining pressure increasing, there was also an approximate linear relation between compressive strength and confining pressure. Full section blasting technique of double order cut and medium-length hole in different depths was adopted to conducted parameter design for drifting blasting of roadway, and blasting parameters was further optimized by field test. And reasonable hole depth of tested roadway was obtained, about 2.0~2.4 m. Field test and application indicated that the utilization rate of hole was over 90%, the average single footage increased by 29%, the rock fragments were more concentrated, and roadway formed in a better shape. This achieved a good blasting effect and a significant economic benefits.

Key words: rock mechanics, hard rock roadway, rapid excavation, drifting blasting, medium-length hole blasting