摘要
对一系列足尺群桩竖向静载荷试验的部分结果进行的分析和总结。试验采用钻孔灌注桩,方案包括单桩、三桩、六桩纯摩擦和端承摩擦桩各一组。首先对试验作了简要介绍。然后对比分析了单桩和群桩、群桩中桩数(桩距)以及端承条件不同(纯摩擦与端承摩擦)等影响因素下,不同方案所得到的基底桩间土反力分布、承台下各桩荷载分配的规律以及桩土荷载分担情况等一系列有意义的结果。试验表明,对于本次试验的具体情况,在桩距为3.08D下,群桩基础桩间土可以分担24%鶫27%的荷载,在桩距4.35D下,可以分担35%鶫42%的荷载。因此,在北京地区可以在桩基设计中适当考虑桩间土分担荷载的作用,同时用改变桩基结构(布桩形式、桩距、端承条件等因素)的方法调整桩土荷载的分布特征和分担比例。
A set of full scale in-situ tests are carried out on group piled foundations in western Beijing. Six static load tests are conducted on instrumented cast-in-place single piles and group piled foundations with different number of piles and bearing conditions. The load distributions under the pile caps are studied, considering the influences of the number of piles, pile spacing and bearing conditions. The measurement results show that 24% - 27% of the total load is borne directly by soil when the pile spacing is 3.08 of the pile diameter, and the ratio is up to 35 % - 42 % when the pile spacing is 4.35 of the pile diameter. Therefore, it is reasonable to consider the bearing capacity of the soil during the design of piled foundation in Beijing Area, and the load distribution ratios can be adjusted by changing layout of the piles, pile spacing, and bearing condition of the pile tip.
出处
《土木工程学报》
EI
CSCD
北大核心
2005年第11期89-95,共7页
China Civil Engineering Journal
基金
北京市科学技术委员会和北京市城乡规划委员会联合下达的“桩基工程差异沉降分析研究”课题的一部分
关键词
群桩基础
桩土反力
荷载分担
现场测试
group piled foundation
reaction force
load distribution
in-situ test
