摘要
双线盾构隧道下穿河道过程中,河道以及地表过度沉降会对周围建筑结构造成损害。为有效控制双线盾构隧道下穿河道过程中的地表沉降,以天津地铁某区间盾构隧道工程为例,分别采用理想弹塑性模型以及小应变硬化特性的有限元数值模拟方法,探究河道交叉角度、河道宽度及注浆压力对河道地表变形特性的影响规律。结果表明:相较于理想弹塑性模型(Mohr Coulomb Model),考虑土体小应变特性的小应变硬化模型(HSS Model)在变形预测方面具有较好的精度。双线盾构隧道施工过程中,随着河岸的交叉角度增大,河道最大沉降量呈现缓慢减少的趋势;地表最大沉降量随着河道宽度增加逐渐减小,河道沉降槽宽度逐渐增加,整体沉降呈现均匀分布形式;此外,适当提高注浆压力可有效降低盾构开挖对河道地表沉降的影响。综上,在盾构设计与施工中,应根据实际情况合理选择盾构下穿位置及掘进参数,降低施工对地表沉降影响以保证工程安全。
During the process of twin-shield tunnel boring beneath a river,excessive settlement of the riverbed and ground surface can cause damage to surrounding building structures.To effectively control ground settlement during this process,this paper uses a section of the Tianjin Metro tunnel project as a case study.The research employs finite element numerical simulation methods,using both ideal elastoplastic and small-strain hardening characteristics to investigate the influence the intersection angle of the river,river width,and grouting pressure on the deformation characteristics of the riverbed surface.The results indicate that compared to the ideal elastoplastic model(Mohr-Coulomb model),the small-strain hardening model(HSS model),which considers the small-strain characteristics of soil,demonstrates superior accuracy in predicting deformation.During the construction of twin-shield tunnels,as the intersection angle of the riverbank increases,the maximum settlement of the riverbed shows a gradual decreasing trend.The maximum ground surface settlement decreases as the river width increases,while the width of the riverbed settlement trough gradually expands,resulting in a more uniform overall settlement distribution.F urthermore,appropriately increasing the grouting pressure can effectively reduce the impact of shield excavation on riverbed surface settlement.In conclusion,when designing and constructing shield tunnels,it is crucial to select appropriate shield types and tunneling parameters based on specific site conditions.This approach helps minimize the impact of construction on ground surface settlement and ensures project safety.
作者
郭雪刚
车炳亿
夏博洋
GUO Xuegang;CHE Bingyi;XIA Boyang(China Railway Airport Construction Group Co.,Ltd.,Tianjin 300000;School of Civil Engineering,Tianjin University,Tianjin 300350)
出处
《现代隧道技术》
CSCD
北大核心
2024年第S01期425-431,共7页
Modern Tunnelling Technology
关键词
盾构隧道
下穿河道
掘进施工
交叉角度
地表沉降
Shield tunnel
Undercrossing channel
Excavation construction
Angle of intersection
Ground subsidence
作者简介
郭雪刚(1985-),男,高级工程师,主要从事隧道及地下工程领域的研究工作,E-mail:405760668@qq.com;通讯作者:夏博洋(1993-),男,博士,助理研究员,主要从事道路以及隧道工程领城的研究工作,E-mail:1019205010@tju.edu.cn.
