地下水封洞库施工巷道开挖爆破技术研究

Study on blasting technology of construction tunnel of underground water-sealed cavern

以国内某地下水封洞库的建设为例对施工巷道的开挖爆破技术进行了研究。首先,基于施工巷道的地质构造特征提出了合理的加固和支护建议。其次,在巷道口近区开挖阶段,对全断面爆破和台阶爆破的效果进行了对比分析;在巷道主体的开挖阶段,对人工钻爆和机械钻爆两种爆破方案的爆破效果效率进行了统计与对比分析。最后,对爆破作用下施工巷道的沉降变形进行了监测分析。研究结果表明:施工巷道口近区经预加固后,全断面爆破与台阶爆破均能满足设计和规范要求,但全断面爆破的施工速率更高;进入巷道主体后采用全断面爆破;人工钻爆与机械钻爆各有优劣势,人工钻爆的施工效率更高,机械钻爆的安全性更高。开挖爆破诱发的位移和沉降均满足设计和相关规范的要求。

This article takes the construction of a groundwater sealed cavern in China as an example to study the excavation and blasting technology of construction tunnels.Firstly,reasonable reinforcement and support suggestions were proposed based on the geological structural characteristics of the construction tunnel.Secondly,a comparative analysis was conducted on the effects of full-face blasting and bench blasting during the excavation stage near the roadway entrance;During the excavation stage of the main body of the tunnel,statistical and comparative analysis was conducted on the blasting efficiency of two blasting schemes,manual drilling and mechanical drilling and blasting.Finally,monitoring and analysis were conducted on the settlement and deformation of the construction tunnel under the action of blasting.The research results indicate that after pre reinforcement in the vicinity of the construction roadway,both full face blasting and bench blasting can meet the design and specification requirements,but the construction rate of full face blasting is higher;After entering the main body of the tunnel,full face blasting is adopted;Both manual and mechanical drilling and blasting have their advantages and disadvantages.The construction efficiency of manual drilling and blasting is higher,and the safety of mechanical drilling and blasting is higher.The displacement and settlement induced by excavation blasting meet the requirements of design and relevant specifications.