低改高高速公路路桥过渡段加宽沉降规律  

Law of widening settlement of road-bridge transition section of low-to-high expressway

作　　者：李友云[1] 安钢 谢继登 赵秀艳 何敏 LI Youyun;AN Gang;XIE Jideng;ZHAO Xiuyan;HE Min(School of Traffic and Transportation Engineering, Changsha University of Science & Technology, Changsha 410114, China;Poly Changda Engineering Co. , Ltd. , Guangzhou 510000, China;Third Construction Co. , Ltd. , China Construction Fifth Engineering Division Corp., Ltd., Changsha 410000, China)

机构地区：[1]长沙理工大学交通运输工程学院,湖南长沙410114 [2]保利长大工程有限公司,广东广州510000 [3]中国建设第五工程局有限公司第三建设有限公司,湖南长沙410000

出　　处：《山东交通学院学报》2021年第1期21-31,共11页Journal of Shandong Jiaotong University

摘　　要：为研究低改高高速公路路桥过渡段加宽后路基的沉降特性,通过有限元建模分析,研究低改高高速公路路桥过渡段加宽的横、纵向断面沉降位移。结果表明:在横断面上,道路沉降主要集中在填筑期及工后5 a内,地基表面竖向位移整体趋近于“盆”形,距离旧路基越远沉降越明显,拓宽侧工后沉降主要集中在2 a内,占工后沉降的64%,在加宽路基中心附近达到最大,水平位移与路基沉降有关。路基拼接位置及加宽路基边坡局部剪应力集中;纵断面上,路基及地基沉降均由桥台向一般路基逐渐增大,差异沉降表现在台后15 m范围内,运营15 a桥台与台后15 m间总差异沉降为7.2 cm,其中工后差异沉降3.0 cm,纵断面剪应力主要集中在台背换填区及桩底区域。In order to study the subgrade settlement characteristics of widened transition section of low-to-high expressway,the settlement displacement of widened transition section of the transverse and longitudinal section of the low-to-high expressway is studied by the analysis of the finite element modeling.The results show that on the cross-section,the road settlement is mainly concentrated in the filling period and within 5 years after construction.The vertical displacement of the foundation surface shows a“basin”trend as a whole.The settlement of the widened side is mainly concentrated in 2 years,accounting for 64%of the post construction settlement and reaching the maximum near the center of the widened subgrade.The horizontal displacement is related to the subgrade settlement.Local shear stress is concentrated at the subgrade splicing position and the widened subgrade slope;on the longitudinal section,the settlement of the subgrade and the foundation gradually increases from the bridge abutment to the general subgrade,and the differential settlement is manifested within 15 m behind the platform.When the 15-year bridge has been operated,the total differential settlement between the platform and the 15m behind the platform is 7.2 cm,of which the differential settlement after construction is 3.0 cm.The longitudinal shear stress is mainly concentrated in the backfill area and the pile bottom area.

关 键 词：高速公路路桥过渡段 地基表面竖向位移 横向沉降位移 纵向沉降位移 桥台 

分 类 号：U418.8[交通运输工程—道路与铁道工程]