摘要
目的研究深基坑锚杆支护结构中锚杆不同参数对深基坑变形的影响,为锚杆支护结构优化设计提供参考.方法基于沈阳地铁北大营街站附属基坑工程,利用岩土有限元软件Midas GTS NX建立基本模型和对比模型,分析施工过程中锚杆锚固长度、锚杆倾角、预应力大小等参数在不同取值范围下基坑的变形情况.结果锚杆锚固长度增加时,基坑变形随之减小,但锚杆对基坑变形的限制效果的增幅随之减小;锚杆倾角增加时,预应力锚杆的作用效果呈先增加后减小的趋势,当锚杆倾角超过20°时,锚杆支护的作用效果急剧减弱;锚杆轴力增加时,基坑变形的减少和预应力的增加接近线性关系,在轴力增量超过200 kN之后,轴力增加不能对基坑变形产生明显的变化.结论在沈阳地区地质条件下,预应力锚杆锚固长度建议取8~12 m,锚杆倾角取10°~20°,预应力取150~200 kN.
The influence of different bolt parameters on the deformation of deep foundation pit is studied in order to provide reference for the optimal design of bolt support structure.Based on the foundation pit project attached to the Beidaying Street Station of the Shenyang Metro,the basic model and comparative model were established using the finite element software Midas GTS NX,and the parameters such as the anchor length,the inclination of the anchor,and the magnitude of the prestress were analyzed during construction deformation of the foundation pit in the range of values.As the anchorage length of the anchor rod increases,the deformation of the foundation pit decreases,but the increase in the effect of the anchor rod on the deformation of the foundation pit decreases.When the inclination of the anchor increases,the effect of the prestressed bolt increases first and then decreases,when the inclination of the anchorexceeds 20 degrees,the effect of the anchor support weakens sharply;when the axial force of the anchor rod increases,the reduction of the foundation pit deformation and the increase of the prestress approach a linear relationship.After more than 200 kN,the increase of axial force cannot cause obvious changes in the deformation of the foundation pit.Under the geological conditions in Shenyang,the ideal and reasonable parameter selection range for prestressed anchors:the anchor bolt length ranges from 8 m to 12 m,the anchor inclination angle ranges from 10 degrees to 20 degrees,and the prestressing force ranges from 150 kN to 200 kN.
作者
李兵
刘阳
李卓伦
刘娜
LI Bing;LIU Yang;LI Zhuolun;LIU Na(School of Civil Engineering,Shenyang Jianzhu University,Shenyang,China,110168;Dandong Commercial Building Design Institute Co.Ltd.,Dandong,China,118000)
出处
《沈阳建筑大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第3期404-411,共8页
Journal of Shenyang Jianzhu University：Natural Science
基金
国家自然科学基金重点项目(51738007)
辽宁省科技厅重点研发计划项目(2019JH8/10100099)
沈阳市科技局项目(Z3318003)。
关键词
深基坑
数值模拟
锚杆参数
有限元
deep foundation pit
numerical simulation
anchor parameter
finite element
