振动沉桩施工对船撞损伤桥墩基础影响的安全距离  

Safety Distance of Vibratory Driven Pile Construction on Pier Foundation Damaged by Ship Collision

作　　者：陈慧芸 冯忠居[2] 谢富贵[3] 王鹏超 李古暄 CHEN Hui-yun;FENG Zhong-ju;XIE Fu-gui;WANG Peng-chao;LI Gu-xuan(School of Architecture and Civil Engineering,Xihua University,Chengdu Sichuan 610039,China;School of Highway,Chang’an University,Xi’an Shaanxi 710064,China;Chengdu Tianfu Greenway Construction Investment Group Co.,Ltd.,Chengdu Sichuan 610041,China;Poly Changda Engineering Co.,Ltd.,Guangzhou Guangdong 510620,China)

机构地区：[1]西华大学建筑与土木工程学院,四川成都610039 [2]长安大学公路学院,陕西西安710064 [3]成都天府绿道建设投资集团有限公司,四川成都610041 [4]保利长大工程有限公司,广东广州510620

出　　处：《公路交通科技》2023年第10期62-72,共11页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金资助项目(51708040);福建省交通运输科技项目(2018Y032)。

摘　　要：为了研究振动沉桩影响下受损桥墩的动力时程响应,确定振动沉桩安全施工距离和合理振动施工参数,避免修复受损桥梁时临时平台的钢管桩振动下沉造成桥梁的二次破坏,结合番禺北斗大桥船撞事故和抢险修复工程现场情况,采用了小孔扩张理论、振动理论和有限元非线性动力分析相结合的方法,确定了沉桩挤土塑性区范围。研究了钢管桩振动下沉时受损墩柱的动力时程响应,确定了振动过程的影响范围及施工安全距离,提出了抢险平台钢管桩振动下沉施工的激振力和振动频率合理范围。结果表明:通过小孔扩张理论计算得到钢管桩振冲下沉过程的挤土效应塑性范围为14.66 m;采用有限元方法模拟振动荷载作用下地基土的速度时程响应,根据现有规范中最大速度限值,得到振动荷载对受损桥墩的径向影响范围为3.02~19.08 m;综合考虑沉桩工艺、沉桩速率、沉桩顺序等工艺,在激振力不超过600 kN情况下,受损墩柱抢险工程钢管桩振冲下沉施工的最小安全距离容许值为15 m;结合数值模拟时程计算和现场工程情况,确定了番禺北斗大桥修复抢险振冲沉桩施工的合理参数,建议钢管柱振冲下沉施工时激振力不超过600 kN、振动频率不低于16 Hz。研究结果可为确保受损桥梁抢险修复工程的施工安全性提供理论支撑和借鉴。In order to study the dynamic time history response of damaged bridge piers under the influence of vibratory driven pile,determine the safe construction distance and reasonable vibration construction parameters of vibratory driven pile,avoid secondary damage to the bridge caused by the vibration sinking of steel pipe piles on the temporary platform during the repair of damaged bridges,and combine the ship collision accident and emergency repair engineering site situation of Panyu Beidou bridge,the small hole expansion theory is adopted.The combination of vibration theory and finite element nonlinear dynamic analysis has determined the plastic zone range of pile sinking and soil compaction.The dynamic time history response of damaged pier columns during the vibration sinking of steel pipe piles is studied,the influence range of the vibration process and the construction safety distance are determined,and a reasonable range of excitation force and vibration frequency for the vibration sinking construction of steel pipe piles on the emergency platform is proposed.The result shows that(1)the plastic range of earth squeezing effect of steel pipe pile in vibro-flushing sinking process is 14.66 m;(2)finite element analysis method is used to simulate the velocity time history response of foundation under vibration load,according to the code,the radial influence range of vibration load on damaged pier is 3.02-19.08 m;(3)considering the factors such as pile driving technology,pile driving rate and pile driving sequence,the allowable minimum safe distance of engineering treatment is given as 15 m,when the exciting force does not exceed 600 kN;(4)the reasonable parameters of vibratory driven pile for Ponyu Beidou bridge restoration are determined by combining history calculation of finite element analysis method and the damaged engineering.It is recommended that the exciting force of the steel pipe column should not exceed 600 kN and the vibration frequency should not be less than 16 Hz.The study result can provide theoretic

关 键 词：桥梁工程 安全范围 数值模拟 受损桥梁 振动沉桩 最小安全距离 

分 类 号：TU473.1[建筑科学—结构工程]