摘要
长短桩复合地基可认为是由单一桩型复合地基按照一定比例组合而成,为探明两者沉降特性之间的关系,利用数值模拟研究了软土地基中柔性桩桩长对两者沉降特性的影响。通过两组不同土层条件、不同桩长的单一桩型复合地基数值模型的分析可知,当桩端位于同一土层时,沉降与桩长之间为线性关系。建立6个不同平均桩长的长短桩复合地基数值模型,分析结果显示,沉降–平均桩长曲线具有明显的特征点,即长桩置换率组合系数为0.5处;随着长短桩桩长差值的增加,长桩置换率组合系数大于0.5的区段趋于一条水平线;且长短桩桩长差值较大模型的沉降–平均桩长曲线总是将差值较小的沉降曲线包络。基于上述分析,提出了软土地基中柔性长短桩复合地基沉降的包络线解法,该方法可较为快捷地得到满足条件的设计方案。
The long-short pile composite foundation can be regarded as a combination of several single-pile composite foundations in a certain proportion.In order to explore the settlement relationship between the two,the influence of the length of the flexible pile in soft soil foundation on settlement of the two is studied by numerical method.According to the numerical analysis of two groups of single-pile composite foundation models with different soil conditions and different pile lengths,the relationship between settlement and the pile length is linear when the pile tip is in the same soil layer.According to the analysis of six numerical models of long-short-pile composite foundations with different average pile lengths,the settlement-average pile length curve has obvious characteristic points,that is,the combination coefficient of long pile replacement ratio is 0.5.As the length difference between long and short piles increases,The part of long pile replacement ratio coefficient greater than 0.5 tends to a horizontal line,and the settlement-average pile length curve of the model with a large length difference between long and short piles always envelops the curve with a small difference.Based on the above analysis,an envelope method for the settlement of flexible long-short-pile composite foundation in soft soil is proposed,which can be used to design the scheme in accordance with the condition quickly.
作者
肖耀廷
杨文钰
XIAO Yaoting;YANG Wenyu(College of Civil Engineering and Architecture,Hubei University of Arts and Science,Xiangyang 441053,China;School of Civil and Hydraulic Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)
出处
《土木工程与管理学报》
2021年第6期126-131,共6页
Journal of Civil Engineering and Management
基金
国家自然科学基金(51878313)。
关键词
复合地基
长短桩
沉降
包络线
平均桩长
composite foundation
long-short pile
settlement
envelope line
average pile length
