地面堆载作用下黏弹性地层盾构施工诱发土体响应时域解  

Time-domain solution for soil feedback induced by shield tunneling in viscoelastic strata considering influences of surcharge loading

作　　者：张治国[1,2,4] 张洋彬[1] 张成平 王志伟 PAN Y T[4] ZHANG Zhi-guo;ZHANG Yang-bin;ZHANG Cheng-ping;WANG Zhi-wei;PAN Y T(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,China;State Key Laboratory for Track Technology of High-Speed Railway,China Academy of Railway Sciences,Beijing 100081,China;Key Laboratory of Urban Underground Engineering of Ministry of Education,Beijing Jiaotong University,Beijing 100044,China;Department of Civil and Environmental Engineering,National University of Singapore,Singapore,119077)

机构地区：[1]上海理工大学环境与建筑学院,上海200093 [2]中国铁道科学研究院高速铁路轨道技术国家重点实验室,北京100081 [3]北京交通大学城市地下工程教育部重点实验室,北京100044 [4]Department of Civil and Environmental Engineering,National University of Singapore,Singapore,119077

出　　处：《岩土工程学报》2021年第1期34-42,共9页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(41772331,41977247);高速铁路轨道技术重点实验室基金项目(2018YJ181)。

摘　　要：目前针对软土地层盾构施工诱发周围土体变形影响的研究一般是基于瞬时开挖工况,较少考虑黏弹性土体的流变特性,也较少考虑地表堆载给盾构隧道施工所带来的影响。从地基黏弹性角度出发,引入隧道洞周的椭圆化收敛变形模式,采用复变函数理论并运用Laplace变换技术,提出了地表堆载作用下盾构隧道开挖引起的周围土体位移和应力的时域解。依托相关工程监测数据与简化时域解对比,得到了较好的一致性。研究结果表明:所得出的时域解能较好地反映地表堆载作用下盾构隧道开挖对周围土体位移场的影响,以及地层变形随时间的发展趋势。在地表堆载影响下,随着时间推移,开挖引起的地层变形不断增加,沉降速率则呈现出逐渐衰弱直至为零规律,而堆载突变导致其地表沉降值尤其沉降速率变化显著。研究成果对黏性地层密集堆载群范围内的隧道施工控制具有一定理论指导意义。At present,the researches on the influences of deformation of surrounding soil induced by shield tunneling in soft soils are generally based on instantaneous excavation conditions,less considering the rheological characteristics of viscoelastic soils.Furthermore,little attention is paid to the impact of surcharge loading on the shield tunneling.From the perspective of viscoelastic foundation,the elliptical convergence deformation mode around tunnel cavity is introduced.Using the complex variable theory and the Laplace transform technique,the time-domain solution for displacement and stress of surrounding soils induced by shield tunneling is proposed under the influences of surcharge loading.Based on the relevant actual projects,the measured values are compared with the simplified analytical solutions,and good consistency is obtained.The results show that the time-domain solution can reflect the influences of shield tunneling on the displacements of surrounding soils under surcharge loading and the development trend of soil deformation with time.Under the influences of surcharge loading,the ground deformation due to tunneling continues to increase as time goes by while the changing rate of soil settlements shows a gradual decline until it reaches zero.The sudden alternation of surcharge loading causes the surface settlement,especially the settlement rate,to change significantly.The research results have certain theoretical guiding significance for tunnel construction controlling within the scope of viscous strata and dense buildings.

关 键 词：盾构隧道 地表堆载 黏弹性 椭圆化收敛变形 时域解 

分 类 号：TU435[建筑科学—岩土工程]