大断面深竖井“先导井、后扩挖”掘进方法在引黄工程中的应用

在水利水电工程中的引水隧洞等工程施工中,经常会遇到竖井开挖。对于竖井开挖,尤其是大断面深竖井开挖,出碴这一环节,往往是决定掘进速度快慢的关键因素。在万家寨引黄工程总干线第三泵站出水压力竖井开挖施工中,采用“先导井、后扩挖”的开挖方法,有效地解决了这一难题。本文以该工程为例,浅析了竖井开挖施工方法。

Application of the Advance Method "Pilot Shaft First, Enlarging Excavation Afterwards" for Large Cross - section and Deep Shaft in the YRDP

The excavation of the large cross-section and deep shaft is often met in the water diversion tunnel of the water and water power project.The spoiling is a key factor influencing the advance speed for the shaft excavation,especially for the excavation of large cross section and deep shaft.The excavation method of "pilot shaft first,enlarging excavation afterwards"was successfully used in the excavation of the outfall pressurized shaft of the third pumping station,the General Main Line of the YRDP.In this paper,the excavation method of "pilot shaft first,enlarging excavation afterwards"is introduced from the following aspects:characteristics,application scope,basic principle,construction technology, blasting,equipment,and construction safety.A case is also given.