短桩桩-网复合地基荷载传递规律及变形特征研究  

Study on Load Transfer Law and Deformation Characteristics of Short Pile-net Composite Foundation

作　　者：商拥辉[1,2] 徐林荣[1] SHANG Yonghui;XU Linrong(School of Civil Engineering,Central South University,Changsha 410075,China;College of Architecture and Civil Engineering,Huanghuai University,Zhumadian 463000,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]黄淮学院建筑工程学院,河南驻马店463000

出　　处：《防灾减灾工程学报》2021年第6期1316-1322,1349,共8页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金项目(51778634,42172322);中国博士后科学基金项目(2020M682589);河南省科技攻关重点研发项目(202102310264);河南省教育厅重点研发项目(20B58003)资助。

摘　　要：为探索中低压缩性土短桩桩-网复合地基荷载传递规律及变形特性,依托赣龙(赣州-龙岩)高速铁路工程背景,借助现场测试数据,分析路堤填筑过程中桩—土应力/荷载分担比、地基沉降及侧向变形规律。结果表明:短桩桩-网复合地基能够有效传递上部附加应力至桩端土层,土压力对上部荷载变化敏感度小于高压缩性软土桩-网复合地基;稳定时桩—土荷载分担比约为50%,桩与土同时发挥承载功效较好;地基沉降在填筑期达到占总沉降90%,侧向变形沿深度呈"弓"型分布,最大侧向变形25 mm,约为高压缩性软土桩-网复合地基60%;桩—土应力对上部荷载变化敏感性高于地基沉降,可依桩—土应力比变化判别地基沉降状态,达到评判工后沉降控制效果目的。In order to explore the load transfer law and deformation characteristics of short pile-net composite foundation,on the basis of the Gan Long(Ganzhou-Longyan)high-speed railway project,field test data was included in this study to analyze the pile-soil stress to load sharing ratio,settlement and lateral deformation of embankment during embankment filling. Results show that:the short pilenet composite foundation can effectively transfer the additional stress to the soil at pile bottom,and the sensitivity of soil pressure to the upper load is less than that of the pile-net composite foundation in high compressible soft soil;stable pile-soil load sharing ratio is about 50%,pile and soil are in good coordination in bearing the loads;90% of the total settlement is completed in the construction period,lateral deformation along the depth shows a bow type with a maximum lateral deformation of about25 mm,which is about 60% of the pile-net composite foundation in high compressible soft soil;comparing to ground settlement,pile-soil stress is more sensitive to the upper loads,so the ground settlement status can be discriminated according to the change of pile-soil stress ratio to assess the control effect of post construction settlement.

关 键 词：桩-网复合地基 荷载传递 变形特性 现场测试 

分 类 号：TU443[建筑科学—岩土工程]