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Abstract Based on testing and analysis of blasting vibration and excavation damage zone(EDZ)，blasting vibration effects of coalmine soft rock roadway excavation and its impact on roadway loose circle radius are researched. The vibration testing and wavelet analysis results indicate that level-radial direction value of blasting vibration velocity is the largest of three directions，velocity of vertical direction is the minimum，so，the level-radial direction velocity can be taken as safety criterion for roadway excavation blasting vibration；main frequency of blasting vibration are more than 100 Hz，80% of the blasting energy concentrated in the range of 100 to 150 Hz，and there are two distinct “sub-band”. Loose circle radius testing and analysis indicate that the loose radius of stabilized roadway is about 1.8 m，and about 10% of it was caused by blasting vibration. Based on this，length of bolt should be lengthened for improving safety and reliability of supporting. According to the research results，technical measures for reduce the vibration effect of coalmine soft rock roadway blasting excavation are given from the blasting parameters and charging structure.
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Received: 21 September 2011
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2012, Vol. 31 
