摘要
裂隙与固结土体的渗透系数差异巨大,裂隙发育的富水固结黏土地层在各方向上的渗透系数极不均匀,管井降水形不成漏斗效应,降水效果很差。但土体自稳性较好,通过地面井点降水与隧道内明排相结合的方式,保证隧道初支开挖的安全、质量、造价和施工效率;二衬施工时通过调整浇筑顺序、增设排水盲沟、多次、多点补注浆等综合措施保证了二衬结构的质量。
The permeability coefficient between fracture and consolidated soil has great difference,the permeability coefficient at every direction is inhomogeneous in water-rich consolidated clay layer with fracture development,tube well dewatering can not form funnel effect,dewatering effect is poor. However,when it comes to fractured water-rich consolidation of clay-like formations,owing to the existence of fissure in stratum,vertical permeability and horizontal permeability have huge difference,and ordinary well dewatering has small radius and can not form a funnel,resulting in the bad effect. In order to ensure the quality,safety and construction efficiency of tunnel excavation in primary support,well-point dewatering on the ground and waterway drain in tunnel are combined. Secondary lining structure quality is ensured in construction by adjusting the pouring order,setting blind drainage ditch,multipoint grouting with many times and so on.
出处
《施工技术》
CAS
2018年第5期109-113,共5页
Construction Technology
关键词
地铁
裂隙
富水地层
固结黏土
暗挖
施工技术
subways
cracks
water-rich stratum
consolidated clay
underground excavation
construction
