超前微桩复合土钉支护三维非线性数值分析  

Three-dimensional nonlinear analysis of composite soil nailing with micro piles for deep excavation

作　　者：宋广[1] 黄建华[1,2] 宋二祥[1] 

机构地区：[1]清华大学土木工程系,北京100084 [2]福建工程学院土木工程系,福建福州350007

出　　处：《岩土工程学报》2010年第S1期151-155,共5页Chinese Journal of Geotechnical Engineering

基　　金："十一五"国家科技支撑计划项目(2008BAJ06B01-5)

摘　　要：结合一基坑支护实例,考虑土体在开挖情况下的变形特性,用三维非线性有限元对单纯土钉支护和微桩复合土钉支护进行了模拟施工过程的计算和对比分析,以对微桩在复合土钉支护中的作用进行研究。部分计算结果与实测的对比,在一定程度上验证了所采用计算模型的合理性。微桩复合土钉支护与单纯土钉支护的对比分析表明,超前微桩的设置在显著减小坑周地层变形、土钉拉力大小以及坑周地表附近地层中拉应力区范围的同时,还会改变坑壁水平位移以及坑边附近地面沉降的分布形式,这可为土钉及复合支护工程的优化设计提供一定参考。Based on a practical foundation pit project,three-dimensional nonlinear finite element analyses are carried out for both soil nailing support and composite soil nailing with pre-installed micro-piles in order to investigate the effect of the micro piles.Attention is paid to consider the characteristics of soil under excavation and to simulate the construction process.Comparison with some measured data and the satisfactory agreements validate the proposed numerical model.Comparative results for support system with and without micro piles show that the micro piles can significantly reduce the soil deformation,nail forces and tension region in the soil close to the ground surface.At the same time they may change the deformation pattern of surrounding soil.These results have reference value for the design of such kind of composite soil nailing.

关 键 词：超前微桩 复合土钉 基坑支护 数值分析 

分 类 号：TU476.4[建筑科学—结构工程]