摘要
为探明软土深基坑开挖及加固施工对近接既有铁路桥梁的影响并评价铁路桥安全性,以福建滨海地区某涉铁软土深基坑工程为依托,结合勘察提供的样本数据及工程特点,构建基于HSS本构的有限元模型,分析各施工阶段对近接铁路桥变形的影响规律。结果表明:典型位置变形的模拟值和实测值基本接近,SMW工法围护结构及软基加固桩施工产生的挤土效应使近接桥墩轻微下沉约0.5 mm,基坑开挖产生的卸载效应使近接桥墩上抬,特别是对位于基坑内的桥墩影响较明显,上抬幅度约为0.3 mm,近桥段开挖使桥墩上抬约为远桥段开挖的两倍,其变形在U型槽施工后基本趋于稳定,最终变形值也满足控制要求。研究结果可为类似工程提供借鉴。
In order to investigate the impact of excavation and reinforcement construction of soft soil deep foundation pits on adjacent existing railway bridges and evaluate the safety of railway bridges,a finite element model based on HSS constitutive model was constructed on the basis of an existing railway-bridge-related soft soil deep foundation pit project in the coastal area of Fujian,combined with sample data and engineering characteristics provided by the survey,so as to analyze the impact of each construction stage on the deformation of adjacent railway bridges.Results indicate that the simulated values of deformation at typical locations are basically close to the measured ones.The soil compaction effect caused by the construction of the retaining structure and soft foundation reinforcement piles with the SMW method has caused slight settlement of the adjacent bridge piers by about 0.5 mm.The unloading effect caused by excavation of the foundation pit has caused the adjacent bridge piers to rise up,especially for the piers located within the foundation pit,with an upward displacement of about 0.3 mm.The uplift caused by excavation near the bridge is approximately twice that caused by excavation far from the bridge.However,their deformation tends to stabilize after construction of the U-shaped groove,and the final deformation value also meets the control requirements.The research results can serve as a reference for similar projects.
作者
胡钟予
刘国买
姚志雄
吴贲
HU Zhongyu;LIU Guomai;YAO Zhixiong;WU Ben(School of Civil Engineering,Fujian University of Technology,Fuzhou 350118,China;Key Laboratory of Underground Engineering of Colleges and Universities in Fujian Province,Fuzhou 350118,China;CCECC Fuzhou Survey and Design Institute Co.,Ltd.,Fuzhou 351111,China)
出处
《福建理工大学学报》
CAS
2023年第6期523-530,共8页
JOURNAL OF FUJILAN UNIVERSITY OF TECHNOLOGY
基金
福建省自然科学基金(2021J011061)。
关键词
既有铁路桥
软土基坑
桥墩位移
Plaxis
3D
位移监测
existing railway bridges
soft soil foundation pits
pier displacement
Plaxis 3D
displacement monitoring