粉质黏土地层管幕+CRD法施工地表变形规律分析——以郑州地铁3号线中州大道站出入口通道工程为例  

Surface Deformation Laws of Silty Clay Strata Induced by Pipe Roofing and Cross Diaphragm:a Case Study of a Passageway Project at Portal of Zhongzhou Avenue Station on Zhengzhou Metro Line 3

作　　者：李义华 朱康康 李明宇[2] 谭建兵 张启瑞 王增辉 LI Yihua;ZHU Kangkang;LI Mingyu;TAN Jianbing;ZHANG Qirui;WANG Zenghui(The 2nd Engineering Co.,Ltd.of China Railway Tunnel Group,Sanhe 065000,Hebei,China;School of Civil Engineering,Zhengzhou University,ZhengzhoU450001,Henan,China)

机构地区：[1]中铁隧道集团二处有限公司,河北三河065000 [2]郑州大学土木工程学院,河南郑州450001

出　　处：《隧道建设（中英文）》2022年第12期2148-2156,共9页Tunnel Construction

基　　金：国家重点研发计划资助(2017YFC1502600);国家自然科学基金项目(51508520);河南省重点研发与推广专项(科技攻关)项目(202102310586);河南省住房城乡建设科技计划项目(K1940,K1817)。

摘　　要：为探究粉土或粉质黏土地层中管幕法+CRD法隧道施工对地表或管线沉降的影响规律,依托郑州地铁3号线中州大道站出入口通道工程,对施工全过程进行分析。研究表明:1)管幕法+CRD法隧道施工大致分为6个阶段,其中管幕施工对地表沉降的影响最为显著;2)管幕顶推导致地表沉降的影响范围超过3倍隧道跨度,地层损失率超出3%;3)3次地表注浆导致的地表抬升量分别占总抬升量的22.43%、28.25%、49.32%,注浆结束后回落量分别占每次抬升量的19.62%、23.03%、5.86%;4)全断面注浆导致地表隆起的影响范围从隧道轴线向两侧扩展到1.6倍隧道跨度。建议管幕顶推时钢套筒壁后应及时注浆,并应实时调整注浆压力和配比;上半断面注浆率应根据地表沉降变化趋势在本工程注浆率的基础上适当下调,下半断面注浆率可以采用本工程建议值;各导洞开挖面应间隔约1倍隧道高度;地层加固施工时注浆率不建议超过6%。Data collected from the entire tunneling process of the passageway project at the portal of Zhongzhou avenue station on Zhengzhou metro line 3 are analyzed to investigate the influence of tunnel in silty or silty clay strata constructed by pipe roof and cross diaphragm(CRD) methods on settlement of surface or pipelines. Results reveal the following:(1) Tunneling by pipe roof and CRD methods can be roughly divided into six stages. The influence of pipe roofing on the surface settlement is the most significant.(2) The influence range of surface settlement caused by pipe roofing is more than three times the tunnel span, and the stratum loss rate is more than 3%.(3) Surface uplifts caused by three times of surface grouting reinforcement account for 22.43%, 28.25%, and 49.32% of the total uplift, respectively,and the surface falling back amounts after each grouting account for 19.62%, 23.03%, and 5.86% of each uplift,respectively.(4) The influence range of surface uplift caused by full-face grouting ranges from the tunnel axial line to both sides(as much as 1.6 times the tunnel span). Therefore, it is suggested that grouting should be timely synchronized behind the wall of the steel sleeve, the grouting pressure should be strictly controlled to prevent pipe blocking, the grouting rate of the upper haft cross-section should be reasonably adjusted according to surface settlement, the grouting rate of the lower haft cross-section can adopt the recommended values, the excavation face of each guide tunnel should be spaced about one times the tunnel height, and the grouting rate should not exceed 6% during the construction of strata reinforcement.

关 键 词：暗挖隧道 粉质黏土地层 管幕法 CRD法 注浆加固 地表沉降 

分 类 号：U45[建筑科学—桥梁与隧道工程]