摘要
针对长江漫滩高承压水地基,以南京青奥轴线—梅子洲过江通道基坑为依托工程,开展格栅地连墙和普通地连墙承载特性的现场试验研究,分别测试研究其墙顶水平位移、墙体深层水平位移、地表沉降、支撑轴力等随基坑开挖及时间的变化规律。主要结论如下:(1)墙顶水平位移在支撑设置后均有回弹变形趋势,变形受支撑架设、预加轴力及拆除影响较大;(2)2种墙体深层水平位移随深度均呈"胀肚型"变化趋势,两者最大侧移均发生在埋深中上部区域;(3)格栅地连墙在基坑开挖初期,地表先小幅隆起,普通地连墙无隆起现象,且沉降明显偏大,两者随距墙体距离增大沉降逐步变小,且不同距离处差异沉降在基坑开挖后期均有增大趋势。
The field test was carried out to the foundation pit at Mei-zi-zhou river-crossing tunnel on Metro Line of Nanjing Youth Olympic Games. The lattice shaped and conventional diaphragm walls were constructed in the ground with high pressure water at Yangtze River floodplain. The variations of lateral displacement at wall top, the horizontal displacement along wall depth, the surface settlement and the axial forces of supporting with the excavation of foundation pit and time were measured and studied respectively. The lateral displacement at the wall top rebounds after the setup of supporting, which is mainly influenced by the supporting installation, pre-axial force and demolition. The deep lateral displacements at the lattice shaped and conventional diaphragm walls tend to form a 'bulging belly' shape, and the maximum deep lateral displacement on both kinds of walls can be found in the middle-upper region of the buried depth. In the early stage of pit excavation, there is a slight surface heave in the lattice shaped diaphragm walls, whereas there is no surface heave but a large settlement in the conventional diaphragm walls. However, the ground settlements are gradually decreased with the increase of the distance away from the walls. The differential settlements away from the walls tend to increase in the late stage of foundation pit excavation.
作者
王新泉
崔允亮
张世民
史庆涛
李兵
WANG Xinquan CUI Yunliang ZHANG Shimin SHI Qingtao LI Bing(Department of Civil Engineering, Zhejiang University City College, Hangzhou, Zhejiang 310015, China China Railway 14th Construction Bureau Co., Ltd., Jinan, Shandong 250022, China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2017年第3期773-780,共8页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金青年项目(51308497)
住房和城乡建设部科学技术项目(2015–K3–020)~~
关键词
地基基础
格栅地连墙
水平位移
地表沉降
支撑轴力
foundation
lattice shaped diaphragmwalls
horizontal displacement
surface settlements
axial forces of support