基于声波检测的空气间隔装药预裂爆破损伤特性研究

Study of Damage Characteristics of Presplitting Blasting with Air-decking Charge base on Sound Wave Tests

采用空气间隔装药预裂爆破技术进行岩体开挖,在提高爆破有效能量利用率的同时,能够取得理想的爆破效果。结合河南省经山寺铁矿上覆岩层剥离进行的空气间隔预裂爆破现场试验,采用声波检测技术,以岩体声波速度降低10%为判据,分析了空气间隔装药预裂爆破对岩体的损伤特性。结果表明,炮孔装药段爆破对岩体的损伤较严重,并有明显的粉碎区,最大深度可达2 m左右,空气间隔段的岩体损伤相对较小。岩体的爆破损伤深度与地质条件以及装药结构密切相关。

The application of presplitting blasting technique of air-decking charge can both improve the use effi- ciency of explosion energy and achieve ideal blasting effect in rock mass excavating. Combined with the field blasting test of iron mine overburden stripping in Jingshan temple of Henan province, the damage characteristics under air- decking charge presplitting blasting was studied base on the sound wave tests and the rock damage zone was set as that the average wave speed reduction was more than 10%. The sound waves tests of the rock mass were taken in the air interval zone and the charging zone respectively. Results show that the rock mass damage was larger in the char- ging zone where smash area was obviously found, and the maximum depth can reach up to about 2 meters. The dam- age characteristics of the rock mess were influenced deeply by the geological conditions and the charging structure.