施工技术2015年12月上 72CONSTRUCTIONTECHNOLOGY第44卷第23期 DOI:10.7672/sgjs2015230072
南水北调东干渠某标段土压平衡盾构施工参数优化研究
苑庆韦,李凌宜²,刘长剑²,姜厚停",龚秋明 (1.北京工业大学城市防灾与减灾教育部重点实验室,北京100124; 2.北京市政路桥股份有限公司,北京100068) [摘要]以北京市南水北调东干渠隧道区间细中砂、粉质黏土混合地层盾构施工为工程背景,对其进行施工参数优 化。
设计了一系列土体改良室内试验,分别对细中砂和粉质黏土进行土体改良优化试验(包括添加剂性能试验和 室内土体改良试验),得到细中砂最佳泡沫注人比为8%,粉质黏土的最佳泡沫注人比为30%,进而根据现场混合 地层细中砂和粉质黏土的体积不同确定最佳泡沫注人比参数为22%,并应用理论方法计算优化盾构开挖面压力取 值范围为100~150kPa。
【关键词】隧道工程;干渠;盾构;开挖面;优化 [中图分类号]U455.43[文献标识码】A[文章编号]1002-8498(2015)23-0072-07 StudyonParameterOptimizationofEarthPressureBalance ShieldConstructioninaContractSectionoftheEastMainCanalof South-to-northWaterTransferProjectinBeijing YuanQingwei',Li Lingyi²,Liu Changjian²,Jiang Houting',Gong Qiuming' (1.KeyLaboratoryofUrbanSecurityandDisasterEngineeringofMinistryofEducation,BejingUniversityfTechnology, Beijing 100124,China;2.Beijing MunicipalRod&Bridge Group Co.,Ld.,Beijing 100068,China) Abstract;Based on shield construction of tunnel section of the east main canal of South-to-north Water Transfer project in mixed stratum with fine medium sand and silty clay in Beijing,the construction
conditioning tests of fine medium sand and silty clay are done respectively including additive performance test and indoor soil conditioning test),draws conclusion that the best foam injection ratio of fine medium sand is 8%,the best foam injection ratio of silty clay is 30%,and then the best foam injection ratio of mixed stratum is 30% which is determined based on the different volume of mixed stratum with fine medium sand and silty clay,the value range of excavation face pressure of the shield is 100 ~150kPa by puting optimization of theoretical methods. Key words:tunnels;main canal; shields;excavation face;optimization 1工程概况及地质条件鱼尾刀贝型刀仿形刀 土压平衡盾构区间为北京市南水北调东干渠切刀 配套工程某标段,掘进机机身全长14.085m,开挖直滚刀 径6.2m,盾构刀盘如图1所示,盾构设计参数如表 1所示。
隧道埋深25m左右,主要穿越地层为细中 砂和粉质黏土层。
试验中所用的土样取自盾构施 工地层中,包括粉质黏土和细中砂。
地质简图如图 2所示,土体参数如表2所示。
[作者筒介]苑庆韦,硕士研究生,E-mail:yuanqingwei6761@126.图1盾构刀盘 [收稿日期]2014-12-12Fig.1 Shield c...