西安地铁盾构隧道含砂黄土地层渣土改良试验研究  

Sand loess stratum muck improvement test study in Xi'an metro shield tunneling project

作　　者：卢艳 Lu Yan

机构地区：[1]西安市地下铁道有限责任公司运营分公司,陕西西安710018

出　　处：《现代城市轨道交通》2018年第6期37-40,共4页Modern Urban Transit

摘　　要：为了解决西安地铁1号线二期工程张后区间下穿既有出入线段土压平衡盾构在砂层中掘进时,方向控制难度大、掘进速度慢、出渣困难、刀盘四周温度过高等问题,从渣土改良控制出发,采用室内试验与场试验结合的方法,通过泥浆黏度试验确定钠基膨润土泥浆最佳浓度和最佳膨化时间;通过常规室内土工试验,测定改良前后的砂土渗透系数、坍落度、内摩擦角和黏聚力,确定采用膨润土泥浆与砂土的体积比;结合实际工程,进一步优化改良渣土,确定最终的改良剂配比。In order to solve the problems occurred in the Phase Ⅱ project of Xi＇an metro line 1 Zhanghou section under-passing the existing entry and exist depot line by earth pressure balance（EPB） shielding in sand stratum, this paper discusses the problem including the diffi cult direction control, slow driving speed, difficult transporting slag, excess temperature around cutter head etc. and uses a combined method of laboratory test and field test, starting from the muck improvement control. With the sodium base bentonite slurry optimized concentration and the optimized expension time by slurry viscosity test and conventional geotechnical tests, it determines sand modified and permeability coefficient, slumps, internal friction angle and cohesion force, confiems the bentonite slurry and sand volume ratio. Based on the actual project, it further improves muck, and determines the finally optimized modifier ratio.

关 键 词：地铁 土压平衡盾构 渣土改良 试验研究 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]