横向流动土体作用下的群桩反应性状  

Behavior of pile groups subject to excavation-induced lateral soil movement

作　　者：韩爱民[1] 肖军华[2] 梅国雄[1] 

机构地区：[1]南京工业大学土木工程学院,江苏南京210009 [2]北京交通大学土木建筑学院,北京100044

出　　处：《岩土工程学报》2005年第12期1463-1467,共5页Chinese Journal of Geotechnical Engineering

基　　金：霍英东青年教师基金(91076);江苏省高校自然科学研究计划资助项目(04KJB560048)

摘　　要：借助FLAC3D程序,分析了基坑开挖后土体横向流动作用下坑内群桩的反应性状。研究了两桩、四桩、五桩、六桩群桩中基桩的反应性状,并与相同位置的单桩反应进行了比较,得到了受横向流动土体作用的群桩相互作用规律:桩基连线平行于边坡布置的两桩,相互影响并不明显;而在其它情况下,前排桩对后排桩遮拦、后排桩对前排桩阻挡,均使受影响的桩基内力分布改变,桩身最大变形量减小;受周围越多、越近桩基的影响,基桩的内力和变位减少得越多。根据桩间土体的成拱特征,定性解释了群桩相互作用的机理与规律,具体工程的现场量测结果也验证了此结论。Three dimensional finite-difference program of FLAC^3D was applied to study pile groups behaviors due to excavation-induced lateral soil movements, including two piles in a row parallel to excavation slope or in a line perpendicular to slope, four-pile, five-pile, 3 × 2 and 2 × 3 pile groups. Comparing the response of a pile among pile groups with that of a single pile located in the same position on slope, the interaction effect in pile groups had been found. Namely, when piles were arranged in a row parallel to slope, the interaction effect between piles was insignificant, while in other arrangements, the existence of either a front pile （a row front piles） or a rear pile （a row rear piles） could all reduce the displacement and maximum bending moment of the adjacent pile, and when a pile was located in groups with small space or among a number of piles, the interaction effect would increasey significantly. These conclusions were explained by arching effects of soil between piles theoretically, and verified by a practical project.

关 键 词：基坑开挖 流动土体 群桩 相互作用 土拱 

分 类 号：TU473[建筑科学—结构工程]