基于空间效应的土岩二元地层深基坑变形规律研究  

Study on deformation laws of deep foundation pits in soil-rock dualistic strata based on space effect

作　　者：宫志群 丁北斗 李阳 马占国 秦天琦 杨继辉 GONG Zhiqun;DING Beidou;LI Yang;MA Zhanguo;QIN Tianqi;YANG Jihui(China Construction Infrastructure Co.Ltd,Beijing 100029,China;School of Mechanics and Civil Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China;China Construction East China Investment Co.Ltd,Xuzhou,Jiangsu 221005,China;China Construction Municipal Engineering Co.Ltd,Beijing 100071,China)

机构地区：[1]中国建设基础设施有限公司,北京100029 [2]中国矿业大学力学与土木工程学院,江苏徐州221116 [3]中建华东投资有限公司,江苏徐州221005 [4]中建市政工程有限公司,北京100071

出　　处：《山东科技大学学报（自然科学版）》2021年第5期87-97,共11页Journal of Shandong University of Science and Technology(Natural Science)

基　　金：中建基础科技研发计划资助项目(CSCIC-2020-KT-(03));徐州市科技局社会发展项目(KC19216)。

摘　　要：为了研究土岩二元地层深基坑的变形规律,以徐州市地铁3号线南三环站深基坑工程为研究对象,监测不同施工阶段基坑围护桩侧移、基坑周边地表沉降和内支护轴力。同时,采用数值模拟方法进一步探究不同刚度放大系数和施工顺序下基坑空间效应的差异性。结果表明:土岩二元地层基坑有明显的空间效应,基坑围护桩变形和周边地表沉降要远小于土质基坑,围护桩最大侧移所处位置的平均值为0.43945倍的开挖深度;随着刚度放大系数的减小,围护桩弯矩增大,基坑长边与短边展现出更加明显的空间效应,而阴角与阳角处的空间效应变化不显著;施工顺序对基坑空间效应有影响,分层施工的空间效应较分区分层施工更加显著。In order to study the deformation laws of deep foundation pits in soil-rock dualistic strata,the study monitored the horizontal displacement of enclosure piles,the surface settlement around the foundation pit and the axial forces of inner supports under different construction stages by taking the deep foundation pit construction of South Third Ring Subway Station of Xuzhou Metro Line 3 as an example.Meanwhile,further research was conducted to analyze the difference of space effect of foundation pits under different stiffness magnification factors and construction sequences by means of numerical simulation.The results show that foundation pits in soil-rock dualistic strata have manifest space effect.Their deformation of enclosure piles and surface settlement are far lower than those of soil foundation pits.The average position of maximum displacement of enclosure piles is 0.43945 times of excavation depth.With the decrease of stiffness magnification factors,the bending moment of piles increases.The long and short sides of the foundation pit exhibits more obvious space effect,but the inner and external corners have less obvious space effect.Construction sequences have an impact on the space effect of foundation pits,which is more obvious under layered construction than that under partition and layered construction.

关 键 词：地铁车站 土岩二元地层 深基坑 空间效应 变形规律 数值模拟 

分 类 号：TU43[建筑科学—岩土工程]