地铁车站出入口工程顶管法施工泥浆被污水渗入后的性能分析  

Performance Analysis of Slurry After Sewage Infiltration in Pipe Jacking Construction of Subway Station Entrances and Exits Project

作　　者：张锟 申政 李少平 李国宾 唐莹 王栋 闵凡路[2] ZHANG Kun;SHEN Zheng;LI Shaoping;LI Guobin;TANG Ying;WANG Dong;MIN Fanlu(Jinan Rail Transit Group Co.,Ltd.,250013,Jinan,China;College of Civil and Transportation Engineering,Hohai University,210024,Nanjing,China;China Railway 21st Bureau Group Rail Transit Engineering Co.,Ltd.,250117,Jinan,China)

机构地区：[1]济南轨道交通集团有限公司,济南250013 [2]河海大学土木与交通学院,南京210024 [3]中铁二十一局集团轨道交通工程有限公司,济南250117

出　　处：《城市轨道交通研究》2024年第9期132-138,共7页Urban Mass Transit

摘　　要：[目的]顶管法施工容易造成施工区域内老化的污水管破裂,进而导致污水沿土体渗入触变泥浆内,对触变泥浆的性能造成一定的影响。为确保施工安全,需研究污水渗入触变泥浆后的性能指标变化规律。[方法]以济南市轨道交通2号线宝华街站1号出入口工程为例,结合该站出入口因顶管下穿导致污水管破裂的施工工况,研究了污水渗入后触变泥浆的性能指标变化规律,并通过减阻试验分析了污水渗入对触变泥浆减阻效果的影响。[结果及结论]污水渗入后,触变泥浆性能发生了劣化,泥浆的漏斗黏度减小,析水率及失水量大幅增加。污水中无机盐的正电荷与泥浆土颗粒的负电荷相互吸引,导致泥浆Zeta电位从稳定的31.0 mV降至20.0 mV以下。污水渗入导致大粒径土颗粒质量分数明显增加,泥浆发生团聚沉淀现象,这是泥浆析水率大幅增加的原因。污水渗入还导致泥浆的减阻效果降低,摩擦因数及顶管顶推力增加。[Objective]During pipe jacking construction,aging sewage pipes within the construction area are prone to rupture,leading to sewage infiltration into the thixotropic slurry along the soil body,thus impacting the performance of the thixotropic slurry to some extent.In order to ensure the construction safety,it is necessary to study the change law of performance indicator after sewage infiltration of the thixotropic slurry.[Method]Using the No.1 entrance and exit project of Baohua Street Station on Jinan Rail Transit Line 2 as a case study,combined with the construction conditions of the sewage pipe rupture due to the jacking pipe underpass at the entrance and exit of the station,the change law of the thixotropic slurry performance indicators after sewage infiltration is studied,and the sewage infiltration impact on the drag reduction effect of thixotropic slurry is analyzed by drag reduction test.[Result&Conclusion]After sewage infiltration,the performance of the thixotropic slurry deteriorates,with a reduction in slurry funnel viscosity and a significant increase in water separation rate and water loss.The positive charges of inorganic salts in the sewage and the negative charges of the slurry soil particles attract each other,causing the slurry Zeta potential dropping from a stable 31.0 mV to below 20.0 mV.Sewage infiltration results in a noticeable increase in the mass fraction of large-size soil particles,and aggregation and precipitation of the slurry,this is the reason for the significant increase in slurry water separation rate.Sewage infiltration also leads to the decrease in the slurry drag reduction effect,with an increase in the friction factor and pipe jacking thrust.

关 键 词：地铁车站 顶管法施工 触变泥浆 污水渗漏 泥浆性能 泥浆减阻效果 

分 类 号：U455.47[建筑科学—桥梁与隧道工程] U231.3[交通运输工程—道路与铁道工程]