煤矿软岩巷道掘进爆破振动特性研究

通过现场爆破振动、松动圈实测和分析，研究煤矿软岩巷道掘进爆破振动效应及其对巷道松动圈半径的影响。振动测试和小波分析结果表明：爆破振动速度3个方向的分量中水平径向最大、垂直方向最小，因此可将水平径向振动速度作为巷道掘进爆破振动的安全评判指标；爆破振动主振频率均＞100 Hz，爆破能量的80%左右都集中在100～150 Hz频带范围内，且存在2个明显的“子频带”。松动圈测试和分析表明：巷道稳定后的松动圈半径为1.8 m左右，其中爆破振动的影响约占10%。据此调整支护参数，增加锚杆长度，提高支护的安全可靠性。在此研究的基础上，从爆破参数和装药结构等方面提出降低煤矿软岩巷道爆破掘进爆破振动效应的措施。

STUDY OF BLASTING VIBRATION CHARACTER OF SOFT ROCK ROADWAY EXCAVATION IN COALMINE

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.