软土地区地铁高架结构不均匀沉降特征与影响因素  

Uneven settlement characteristics and influence factors of metro elevated structures in soft soil region

作　　者：吴楠[1,2] 肖军华[3] WU Nan XIAO Jun-hua(School of Civil Engineering, Beijing J iaotong University, Beijing 100044, China Kunshan Rail Transit Investment and Development Co. , Ltd. , Kunshan 215332, Jiangsu, China Key Laboratory of Road and Traffic Engineering of Ministry of Education, Tongji University, Shanghai 201804, China)

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]昆山市轨道交通投资发展有限公司,江苏昆山215332 [3]同济大学道路与交通工程教育部重点实验室,上海201804

出　　处：《交通运输工程学报》2017年第2期12-20,共9页Journal of Traffic and Transportation Engineering

基　　金：国家自然科学基金项目(51678447)

摘　　要：为了探究软土地区某地铁高架结构不均沉降发展特性,选取某地铁运营线高架段,进行了为期2年的沉降观测,观测结构包括:高架车站、高架区间的简支梁桥与2座大跨连续梁桥;分析了地铁高架结构的桥墩、道床不均匀沉降特征及其影响因素,研究了地铁高架线路在建设期与运营期沉降的发展规律。分析结果表明:该线路运营2年后,桥墩累计沉降(相对运营开始的沉降)最大值为12.4mm,并仍有继续发展趋势,地铁周边的建筑工程活动使全线共形成6个明显的沉降槽,总体上相邻桥墩差异沉降小于2 mm;高架车站的桥墩沉降以建设期为主,建设期最大累计沉降为17.5mm,建设期与运营期最大累计总沉降为18.8mm;在建设期与运营期高架区间桥墩沉降无明显差异,建设期最大累计沉降为14.2mm,建设期与运营期最大累计总沉降为23.9mm;高架区间简支梁桥上的道床板大部分为上拱变形,最大变形为8.9mm,而大跨连续梁桥主跨上的道床板下挠变形较显著,跨径为129m的连续梁桥道床板最大挠曲变形达29.2mm。In order to study the uneven settlement characteristics of elevated structures of a metro line in soft soil region, a long-term settlement observation was carried out during construction period and operation period, and the observed objects included elevated stations, elevated intervals with prestressed concrete simply supported beam bridges and large-span prestressed continuous bridges. The uneven settlement characteristics of piers and track beds of elevated substructures and their influence factors were investigated, and the settlement development rules during operation period and construction period were compared. Analysis result shows that after 2 years of operation, the maximum settlement of piers is 12.4 mrn with relative to the beginning settlement of operation, and there is still a trend of continuous development. Six settlement troughs are observed on the studied metro line because of the activities of construction engineering around the metro line. Totally, the differential settlements of adjacent piers are less than 2 mm. The settlement of elevated station mainly generates during construction period, the maximum accumulative settlement is about 17.5 mm at the moment, and the total maximum accumulative settlement only is 18.8 mm during both construction period and operation period. The differential settlements of bridge piers in elevated intervals are unconspicuous during both construction period and operation period, the maximum accumulative settlement during construction period is 14. 2 ram, and the total maximum accumulative settlement is 23. 9 mm during both construction period and operation period. Most of ballast bed slabs on simple support beam bridge in elevated intervals have upward deformations, and the maximum deformation is 8.9 mm. While the ballast bed slabs on the main spans of large-span continuous beam bridge have large deflections, and the maximum deformation is 29.2 mm. 4 tabs, 14 figs, 25 refs.

关 键 词：软土地区 地铁高架结构 桥墩 道床 差异沉降 

分 类 号：U443.22[建筑科学—桥梁与隧道工程]