深厚软土层端承摩擦桩桩承式加筋低路堤现场试验  

A Field Test of Geosynthetic-reinforced Pile-supported Low Embankment with End-bearing Friction Piles on Deep Soft Soil

作　　者：刘浩[1] 高泉平 李纪昕 李良昊 张颖 丁锐恒 芮瑞 LIU Hao;GAO Quanping;LI Jixin;LI Lianghao;ZHANG Ying;DING Ruiheng;RUI Rui(East China Company of China Construction Second Engineering Bureau Ltd,Shanghai 200135,China;Capital Construction Division,Wuhan University of Technology,Wuhan 430070,China;School of Civil Engineering and Architecture,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]中国建筑第二工程局有限公司华东公司,上海200135 [2]武汉理工大学基建处,湖北武汉430070 [3]武汉理工大学土木工程与建筑学院,湖北武汉430070

出　　处：《土木工程与管理学报》2023年第6期60-69,共10页Journal of Civil Engineering and Management

基　　金：国家自然科学基金(42272315);中国建筑第二工程局有限公司科技资助计划(CSCEC-2019-Z-29)。

摘　　要：为揭示桩承式加筋低路堤的荷载传递机理及土工格栅的加固效应,选取武汉智能网联赛车道项目主赛道连接段某低路堤路段开展了一个承载单元的现场试验,分别测试了施工期桩帽顶部与格栅上层的土压力分布、路堤分层沉降、格栅应变与挠曲。数据分析表明:随着填土高度的增加,土拱效应与张拉膜效应逐渐发挥,桩帽顶部的土压力开始超过桩间土压力并在填筑结束后逐渐趋于稳定。在端承摩擦桩桩承式加筋低路堤的荷载传递机制中,桩间土承担主要荷载,占比62.23%,张拉膜效应仅占很小一部分,占总荷载的3.77%。土工格栅的最大应变出现在桩帽边缘处,但最大值仅为0.195%,这表明土工格栅性能难以得到充分发挥。在该桩承式加筋低路堤中,两桩中心处的桩间土沉降要明显大于四桩对角线中心处。For revealing the load transfer mechanism of GRPS low embankment and geogrid reinforcement effect,a field test is carried out on a bearing unit selected from the main track connection section of a racing track project.The soil pressure distribution of the top of the pile cap and the upper part of the geogrid,the layered settlement of the embankment,and the strain and deflection distribution of the geogrid were tested respectively by the test elements buried in the field.Field test results show that with the increase of the filling height,the soil pressure at the top of the pile cap began to exceed the soil pressure between piles due to the soil arching effect and the tension membrane effect,and gradually stabilized with the completion of filling.In the load transfer mechanism of geosynthetic-reinforced and end-bearing friction pile-supported low embankments,the soil between piles still bears the main load,accounting for 62.23%.The tensile membrane effect of geogrid only accounts for a small part,which is only 3.77%of the total load.The maximum strain of the geogrid occurs at the edge of the pile cap,but the maximum value is only 0.195%,and there is still much room to play.In this GRPS low embankment,the settlement of soil between piles at the center of two piles is significantly greater than that at the diagonal center of the four piles.

关 键 词：桩承式加筋路堤 端承摩擦桩 现场试验 格栅挠曲与应变 土拱效应 张拉膜效应 

分 类 号：U416.12[交通运输工程—道路与铁道工程]