西安东北二环立交桥桩基的力学特性分析  

Analysis of Mechanical Property of Pile Foundation of Overpass on Northeast 2nd Ring Road of Xi' an

作　　者：彭永涛[1] 宋海民[2] 刘金梅[3] PENG Yongtao SONG Haimin LIU Jinmei(School of Highway, Chang＇an University, Xi＇an 710064, China Shanxi Audit Office, Xi＇an 710002, China China University of Mining ＆ Technology （Beijing）, Beijing 100083, China)

机构地区：[1]长安大学公路学院,西安710064 [2]陕西省审计厅,西安710002 [3]中国矿业大学(北京),北京100083

出　　处：《路基工程》2017年第1期132-137,共6页Subgrade Engineering

摘　　要：为深入研究黄土区域桩基的荷载传递特性,以西安东北二环立交桥桩基为对象,基于锚桩-横梁反力装置,采用慢速维持荷载加载法进行现场静载试验,研究了简化计算法与轴力线性计算法下的桩顶沉降与桩身压缩之间的关系。研究结果表明:黄土浸水稳定结构重塑之后,桩侧土层承载力变化幅度较小;试桩受压产生向下位移对湿陷变形起一定带动作用,桩周土体沉降显著;未浸水试桩桩顶荷载Pt与极限荷载Pu之比为0.6时,桩顶沉降主要为桩身弹性压缩,当Pt/Pu大于0.6时,桩端沉降速度明显增加。In order to deeply research and analyze the load transfer characteristics of pile foundation in loess area, a field static load test is made for the pile foundation of on overpass on Northeast 2nd Ring Road of Xi＇an by anchor pile counterforce device in slow maintained load loading method to research the relationship between pile top settlement and pile compression by simplified calculation method and the axial force linear calculation method. The results show that the bearing force of the soil around the pile changes to a lesser extent after remodeling the stability structure of loess immersion; trial pile is pressed to generate downward displacement plays a leading role of collapsible deformation, the soil around load P, to ultimate load P u of unsoaked test pile is 0. 6, pile compression of the pile body , when Pt/Pu is greater than 0. 6, the pile settles obviously; when the ratio of top top settlement is mainly caused by the elastic pile tip settling velocity increased significantly.

关 键 词：静载试验 简化计算法 轴力线性计算法 桩顶沉降 桩身压缩 

分 类 号：TU473.12[建筑科学—结构工程]