基坑开挖地表沉降影响因素及关联度研究

摘要

城市地铁基坑工程开挖，打破了土体原始平衡，影响已建建筑物安全，地表沉降是反应施工影响的重要而又直观的因素。论文对基坑地表沉降的影响因素的作用机理进行了分析，在此基础上，应用灰色关联度分析理论，构建某地铁基坑工程地表沉降量与桩顶水平位移、深层位移、地下水位、支撑轴力、锚索拉力等监测项目之间的灰色关联度模型，得出地表沉降与各因素的关联度。结果表明：影响地表沉降的因素关联度大小顺序是桩顶水平位移、锚索拉力、地下水位、深层位移、支撑轴力。论文为以后研究地表沉降规律及类似工程监测方案优化提供理论依据。%The excavation of city subway pit breaking the original balance of the soil,affecting existed buildings’ safety,the surface subsidence of construction are the important and intuitive factors which react construction impacts. Use of the Grey Relational Analysis Theory,through monitoring measured data of factors,builds gray correlation analysis a-mong excavation of subway construction surface subsidence,horizontal displacement of pile top,deep displacement,the groundwaterlevel,strut axial forces, the anchor cable tension and other factors, getting the collective degree of different monitoring program. The results show that,in order of size of collective degree of factortwhich affect surfacesubsidence, horizontal displacement of pile top,anchor cable tension,the groundwater level,deep displacement,Strut axial forces. It provides a theoretical basis for law of surface subsidence and similar monitoring program optimization in the future pro-jects.