摘要
为解决大断面隧道钻爆法施工中钻孔数量大导致的钻孔成本高、施工进度慢的难题,提出了大断面隧道爆破减孔布设的新理论、新方法,将掏槽孔布置位置最大限度“向外推”,为辅助孔和解炮孔提供双向临空面,从而实现中间岩体宽孔距减孔布设,以雷榕高速公路白竹山隧道为工程依托,开展了现场爆破试验。试验结果表明:通过掏槽孔适当外推,中间岩体减孔布设,每循环钻孔数量可减少23个,节约钻孔时间0.6 h,全线59 km隧道将节约打孔时间约8850 h;减孔布设后,超挖厚度控制在15 cm以内,喷混超耗率控制在90%以内,爆破效果良好。
In order to solve the problems of high drilling cost and slow construction progress caused by a large number of holes to be drilled in the large-section tunnel drilling and blasting operation,a new method for reducing blast holes is proposed.The method maximizes the outward placement of cut holes to provide a two-way free face for auxiliary holes and blast holes,thereby realizing wide hole spacing in the middle rock mass with the reduced hole layout.On-site blasting tests were carried out in the Baizhushan Tunnel of the Lei-Rong Expressway.The test results show that through proper outward placing of cut holes,the central rock mass hole arrangement can reduce the number of drilling holes by 23 per cycle,saving 0.6 h of drilling time and about 8850 h for the entire 59 km tunnel,with the thickness of over-excavation controlled within 15 cm and the over-consumption rate of spray mixing within 90%,which means the method could achieve a good blasting effect.
作者
娄乾星
陶铁军
田兴朝
朱海明
张林
郑仕跃
LOU Qian-xing;TAO Tie-jun;TIAN Xing-chao;ZHU Hai-ming;ZHANG Lin;ZHENG Shi-yue(School of Civil Engineering,Guizhou University,Guiyang 550025,China;China Overseas Construction Co.,Ltd.,Shenzhen 518000,Guangdong,China;Guizhou Transportation Planning Survey&Design Academe Co.,Ltd.,Guiyang 550000,China)
出处
《工程爆破》
CSCD
北大核心
2022年第2期54-61,共8页
Engineering Blasting
基金
国家自然科学基金地方基金资助项目(52064008)。
关键词
大断面隧道
减孔布设
楔形掏槽孔
现场试验
超挖
large section tunnel
reducing hole layout
wedge cut hole
field test
over excavation
