南水北调穿黄隧洞大断面深竖井切割拆除技术

Cutting and Removal Technology of Large Cross Section and Deep Shaft in Tunnel Across Yellow River of South-to-North Water Diversion Project

为保证南水北调中线穿黄隧洞结构在洪水与地震工况下的安全,待南岸竖井隧洞段结构全部施工完成后,需将南岸大断面深竖井拆除,以保证隧洞通水运行安全。原计划采用爆破方案,在南岸竖井高程85 m处将竖井地连墙和内衬钢筋切断后,对高程85 m以上进行一次性爆破拆除。后来为保证拆除方案的安全可靠,采取对南岸竖井自下而上分层环向切割、内部回填土的处理方案。在不进行大规模爆破拆除施工条件下,采取绳锯切割法分段切割并回填密实,成功完成了南岸竖井拆除。

In order to ensure the structure safety under the flood and earthquake conditions in the tunnel across the Yellow River of the South-to-North Water Diversion Project, it is necessary to remove the large cross section and deep shaft when the construction of shaft tunnel structure was completely finished.The blasting scheme which set one-time demolition to the elevation more than 85 m after the cutting of bars between the wall and lining in the shaft height of 85 m place was adopted by the original plan.Then for the security of removing plan, the treatment scheme which set the bottom-to-up hierarchical ring to cutting and backfills the inside was accepted.Under the conditions of without blasting and removing on a large scale, the removal of south shaft was successfully completed through the wire saw cutting and compacted backfill method.It had been found that both the cutting and backfill qualities had met the design requirements.