砂桩群桩复合地基模型试验研究  

Model tests on composite foundation with group sand piles

作　　者：朱小军[1] 龚维明[1] 赵学亮[1] 

机构地区：[1]东南大学土木工程学院,江苏南京210096

出　　处：《岩土工程学报》2013年第S2期680-683,共4页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51079030);国家科技支撑计划项目(2011BAG07B01);国家重点基础研究发展计划(973计划)项目(2013CB036304)

摘　　要：为了深入研究砂桩复合地基加固体系的承载力、沉降及破坏机理,通过自行研发的可视化模型试验装置,对砂桩单桩、群桩复合地基进行了2组室内模型试验,并进行了1组钢管桩单桩复合地基对比试验,获得了砂桩复合地基的荷载–沉降、桩土应力比、沉降–时间及桩土应力比–时间数据。试验结果分析表明:钢管桩单桩复合地基与砂桩单桩复合地基相比,其承载力低,且桩顶应力集中现象明显;砂桩群桩复合地基总沉降量小,承载力高,沉降及桩土应力比时间效应显著,桩体置换作用明显,充分发挥了桩间土的承载特性。To deeply study the bearing capacity, settlement and failure mode mechanism of composite foundation with sand piles, single and group sand piles composite foundations with as well as contrast tests on the composite foundation with steel pipe piles are performed. designed and carried out in the laboratory model tests. The data about the load-settlement, pile-soil stress ratio, settlement-time and pile-soil stress ratio-time are obtained. The results show that the bearing capacity of the composite foundation with single steel pipe pile is lower, and the stress concentration on the pile top is more obvious, compared with that of the composite foundation with single sand pile. The composite foundation with group sand piles is of low settlement, high bearing capacity, significant time effect of settlement and pile-soil stress ratio, obvious pile replacement and full improvement of the bearing capacity of the soils between piles.

关 键 词：砂桩 复合地基 模型试验 时间效应 

分 类 号：TU470[建筑科学—结构工程]