摘要
Abstract
Based on the project background of Section 3,Lot 1,Shenzhen Airport-Daya Bay Intercity Railway Tunnel Project of Shiyan Central Station-Longsheng Station section,for Work Shaft No.1(depth of 63.7 m,inner diameter of 33.0 m,with a horizontal clear distance of only 27.9 m at the bottom of the shaft)without pilot tunnels,the ex-tremely space-constrained problem of bidirectional launch for two large-diameter shield machines simultaneously was solved and bidirectional large-split launching technology for shield machines in pilot-tunnel-free shafts was developed.The core innovations include:1)A excavation technology without an equipment bridge,utilizing a tem-porary bridge integrated with a foam/grease platform and segment hoist to replace conventional connection bridges.2)A vertically layered arrangement of gantries,constructing multi-level steel platforms in the central shaft-bottom area to arrange essential backup gantries vertically and maximize space utilization.3)A bidirectional coordinated split launching process,pioneering a three-phase synchronous bidirectional launching procedure within the same shaft(shield main body+temporary bridge →the integrated No.1 Cart → complete gantry formation).Application results demonstrate the successful bidirectional launch of two shield machines,achieving a reduction of approxi-mately 4 937.7 m3 in pilot tunnel excavation,a project duration shortened to 160 days(28.6％savings than conven-tional methods).And a 41.0％and 17.2％improvement in thrusting and segment assembly efficiency respectively in Phase 2 than Phase 1,significantly reduced construction risks and costs as well.This technology provides a stan-dardized solution for shield tunneling in ultra-deep confined shafts.关键词
大直径盾构/无导洞竖井/双向/分体始发Key words
large-diameter shield machine/shaft without pilot tunnel/bidirectional/split launching分类
交通工程
