复合地层盾构机刀盘结泥饼成因及预防措施

Formation and Precautions of Mud Cakes in Mixed Strata

复合地层盾构掘进中,盾构机刀盘结泥饼问题是影响地铁隧道施工的一大难题。泥饼的存在,不仅会造成盾构机刀盘扭矩和推力的增大,推进速度减慢,施工效率降低,还会造成刀具磨损,进而导致盾构机损坏,甚至严重影响施工进度和施工安全。本文以福州地铁某区间隧道工程为例,从区间隧道的地质条件、盾构机刀盘的开口率、刀具的启动扭矩与复合地层不同土层强度变化较大的矛盾、土仓长时间充填黏性土、渣土改良及掘进模式等五个方面分析了泥饼形成的原因和机理,并提出了防止泥饼形成的施工措施,提供了解决此类问题的思路及途径。

Mud cakes may become a big challenge when shield machine excavates in the mixed strata condition.It is easy to form mud cake on cutter head,which not only increases the torque of cutter,leading to lowering efficiency of construction,but impairs the process and safety of the construction.This paper analyzes the reasons for the occurrence of mud cakes from geotechnical conditions,the aperture ratio of cutter head,the problems of shield tools break-out torque and the soil strength of compound stratum,the soil bin filled with viscous soil,sediment improvement and control of shield construction,then it puts forward the guidance to prevent the mud cakes and counter measures for similar projects.