摘要
隧道开挖会影响周围土体自由位移场,造成邻近建筑结构的变形与应力重分布,随着扰动软土固结,建筑结构变形持续产生。目前,既有理论方法较少考虑上部建筑结构刚度对基础变形的耦合制约效益以及扰动土体的固结影响。文章基于子结构刚度凝聚法和固结有限层地基,提出软土隧道开挖对邻近浅基础框架结构变形影响的简化分析方法,主要研究了受隧道开挖和软土固结影响的基础沉降、上部框架变形和内力,并针对固结时间和土体渗透系数进行了参数分析。结果表明:该简化分析方法与有限元结果较为吻合,框架基础因固结产生的沉降增量约占整体沉降的6%,其影响不可忽略;框架结构中柱受拉,两侧柱受压,两侧梁、柱交点均发生向中柱的转动,梁和基础产生下凹变形;渗透系数主要影响土体固结速度,对土体的固结沉降增量几乎没有影响,渗透系数越小,框架变形和弯矩变化越慢,浅层土体的渗透系数对受扰动后土体固结速度的影响最大。
Tunnel excavation will change the free displacement field of the surrounding soils,causing the deformation and stress redistribution of the superstructure.With the consolidation of disturbed soil,the deformation of the superstructure gradually occurs.Currently,the coupling influences of the stiffness of building on the foundation deformation and the soil consolidation are usually ignored in present theoretical analytical methods.Based on the substructure stiffness coherence method and the theory of consolidation finite layer,a new method is proposed to analyze the influences on the deformation of adjacent frame buildings with shallow foundation induced by tunnel excavation.The method is used to calculate the foundation settlement,building deformation and internal forces of the frame buildings.A parametric analysis is conducted along with it.Results show that this method is in good agreement with the FEM.The settlement of foundation increment caused by the effect of consolidation is about 6%of the total settlements,the influence can not be ignored.The middle columns of the frame are pulled,the bilateral columns are pressed,both sides of the cross points of beams and columns are turn to the middle column and the deformation of beams and foundations is concave.The permeability coefficient mainly affects the consolidation velocity of the soil and has little effect on the settlement of the soil consolidation.The penneability coefficient in the shallow layer has the most significant impacts on the velocity of the consolidation.The smaller the permeability coefficient is,the slower the frame deformation and bending moment changes,the permeability coefficient also has an obvious influence on both the deformation and the bending moment of the frame.
作者
张治国
张成平
奚晓广
费思异
ZHANG Zhiguo;ZHANG Chengping;Xi Xiaoguang;FEI Siyi(School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093;Shandong Provincial Key Laboratory of Marine Ecology Environment and Disaster Prevention Mitigation, Qingdao 266033;Key Laboratory of Urban Underground Engineering of Ministry of Education,Beijing Jiaotong University,Beijing 100044;Engineering Research Center of Rock-Soil Drilling and Excavation and Protection,Ministty of Education,Wuhan 430074)
出处
《现代隧道技术》
EI
CSCD
北大核心
2018年第A02期1028-1042,共15页
Modern Tunnelling Technology
基金
国家自然科学基金项目(41772331)
山东省海洋生态环境与防灾减灾重点实验室项目(201703)
岩土钻掘与防护教育部工程研究中心课题(201705)
北京交通大学城市地下工程教育部重点实验室开放基金(TUE2017-04).
关键词
固结有限层
浅基础框架
隧道开挖
基础沉降
框架变形
框架弯矩
Consolidation finite layer
Frame buildings with shallow foundation
Tunnel excavation
Foundation settlement
Frame deformation
Bending moment of frame
