摘要
为研究透水混凝土桩复合地基的承载特性,采用模型试验获得了分级加载过程中的沉降、桩土应力比、桩身侧摩阻力和孔压消散规律.结果表明,骨料粒径为3~5 mm、孔隙率为30%的透水混凝土模型桩可以兼顾强度和透水性.处理饱和粉土地基时,相比不透水混凝土桩复合地基,透水混凝土桩复合地基使固结时间缩短30.3%,侧摩阻力平均提升0.12 kPa,并降低了荷载引起的超孔压峰值.水平方向越靠近桩体,透水混凝土桩的排水减压作用越明显.对比不同深度的超孔压峰值,靠近桩体时,透水混凝土桩对上部地基的排水减压效果较好,而远离桩体时,透水混凝土桩对下部地基的排水减压效果较好.透水混凝土桩可以快速提高桩周土体的承载能力.
To investigate the bearing characteristics of the pervious concrete pile composite foundation,the settlement,the pile-soil stress ratio,the side friction and the pore-water pressure during the multi-stage loading were obtained by model tests.The results show that both strength and permeability can be achieved for the model pervious concrete pile with the aggregate size of 3 to 5 mm and the porosity of pervious concrete of 30%.When treating the silt foundation,compared with the impervious concrete pile composite foundation,the pervious concrete pile composite foundation can shorten the consolidation time by 30.3%,and increase the side friction with an average value of 0.12 kPa.During the loading process,the pervious concrete pile can significantly reduce the peak value of the excess pore-water pressure.The closer the horizontal direction distance to the pile body,the more obvious the dissipation effect of the pervious pile.As for the peak values of excess pore water pressure at different depths,the pervious pile exhibits a better effect on the drainage decompression of the upper foundation when it is closer to the pile.However,the drainage decompression effect of the lower foundation is better when it is far from the pile.The pervious concrete pile can quickly increase the soil bearing capacity.
作者
杜广印
蔡俊
孙长申
夏涵
章定文
Du Guangyin;Cai Jun;Sun Changshen;Xia Han;Zhang Dingwen(Institute of Geotechnical Engineering,Southeast University,Nanjing 211189,China;Zhejiang Provincial Institute of Communications Planning,Design and Research,Hangzhou 310006,China)
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2020年第5期814-821,共8页
Journal of Southeast University：Natural Science Edition
关键词
透水混凝土桩
复合地基
承载特性
模型试验
pervious concrete pile
composite foundation
bearing characteristics
model test
