RESEARCH AND APPLICATION OF THE CUTTING BLASTING TECHNOLOGY OF ROADWAY EXCAVATION IN HARD ROCK

Based on the campaign laws of rock fragments and detonation gas in the groove cavity of cutting blasting,the paper analyzed the main influencing factors of cutting blasting.Selected out the reasonable cutting pattern and blasting parameters based on the test results performed in site by comparing the three cutting patterns of the the inverse triangle,single helixand the rectangular.The construction practice indicated that the blasting efficiency in drif was improved and good economic benefits were obtained by the adoption of the rectangular cutting pattern.