道路下穿既有铁路顶进双层框架深基坑施工技术研究  

Deep Foundation Pit Construction Technology for Jacking Process Double-layered Frame in Road Under-passing Existing Railway

作　　者：郑丹 ZHENG Dan(China Railway Shanghai Design Institute Group Co.,Ltd.,200070,Shanghai,China)

机构地区：[1]中铁上海设计院集团有限公司,上海200070

出　　处：《城市轨道交通研究》2023年第S02期86-91,共6页Urban Mass Transit

摘　　要：上海市万荣路-三泉路道路下穿铁路南何线的立交工程,为临近既有线顶进施工框架桥,采用(8.4+8.4+7.50)m框架桥,长度为27 m,顶进基坑深度约为12.17 m,周边建筑和管线多。临近正常运营既有铁路的顶进框架很少有达到如此大的基坑深度,为此重点研究了框架深基坑中的关键技术。经过多方案比选,基坑3个侧面采用了双排钻孔桩围护加系梁的围护方式,顶进前端采用了放坡开挖结合钻孔桩防护。该方案有效防护了既有铁路和基坑的安全。The elevated transportation project of Wanrong Road-Sanquan Road under-passing the Nan-He(NanxiangHejiawan)Railway Line in Shanghai is jacking construction of frame bridge in proximity of existing line,which adopts a(8.4+8.4+7.5)m double-layered frame bridge for construction.The bridge spans 27 m,and the depth of the jacking foundation pit is approximately 12.17 m.The construction site is surrounded by numerous buildings and pipelines.Few jacking frame constructions in proximity of existing railways in normal operation have achieved such a significant excavation depth.For this purpose,key technologies for deep foundation pit within the frame structure is emphatically studied.After evaluating multiple schemes,the retaining mode that employs a double-row drilled pile retaining structure with tied beams for the three sides of foundation pit and a combination of slope excavation and drilled pile protection at the front-end of the jacking process is selected.This solution effectively ensures the safety of the existing railway and foundation pit.

关 键 词：道路-铁路立交 下穿式立交 顶进施工 深基坑 双层框架 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]