广州海珠桥原悬索钢桁架主桥安全监测
|
摘要
广州海珠桥历经多次改造,2011年检测判定主桥[(67.79+49.10+67.79)m三跨连续索桁组合结构]为危桥需抢修,为确保抢修施工前桥梁的运营安全,进行安全监测。建立主桥计算模型,按实测的材料物理力学强度、吊杆力、主缆拉力及钢结构杆件锈蚀率等指标,对模型部分参数进行修正;在恒载+汽-15活载+人群荷载组合下,进行承载能力验算,确定最不利受力杆件。安全监测时,在应力较大的22根杆件布置应力监测点,竖向变形监测点选取桥跨L/2、L/4、L/8及支点等关键截面;根据桥梁承载能力验算结果和容许应力法,确定各监测杆件的应力预警值和边跨、中跨挠度预警值。结果表明,修正的计算模型能准确模拟结构真实受力状况;监测参数及预警值设置合理;监测周期内,各杆件应力增量均未超过预警值,各测点最大挠度增量在2mm范围,小于预警值,结构处于安全状态。
The Haizhu Bridge in Guangzhou had experienced multiple times of renovation.The main bridge is a combined suspension and steel truss structure with three continuous spans of 67.79,49.10 and 67.79 m.The inspection in 2011 confirmed that the main bridge was a dangerous structure needing immediate strengthening.To ensure the operation safety of the bridge before the strengthening,the safety condition of the bridge was monitored.The calculation models of the bridge were established,and the models were modified by a series of measured data,including the physical and mechanical strength of the materials,hanger forces,tensile strength of the main cables and the corrosive ratio of the members of the steel structure.The load bearing performance was checked under the combined loading condition of dead load,vehicles with a loading capacity of 15 tand pedestrian loads,to find out the members in the most unfavorable loading state.During the safety monitoring,sensors were installed on the 22 members bearing bigger stresses,and the critical cross-sections,like the L/2,L/4,L/8 and the supports,were selected for vertical deformation monitoring.Based on the checking results of the load bearing capacity of the bridge as well as the allowable stress method,the warning stress values of the members monitored and the warning deflection values of the side spans and the middle span were determined.The results show that the calculation models modified can accurately simulate the real load bearing condition of the structure.The monitoring parameters and the warning values selected were proper.The stress increment of each member in the monitoring period did not surpass the warning values.The maximum deflection increment of each testing point was not bigger than 2 mm,less than the warning value,and the structure was in safe condition.
The Haizhu Bridge in Guangzhou had experienced multiple times of renovation.The main bridge is a combined suspension and steel truss structure with three continuous spans of 67.79,49.10 and 67.79 m.The inspection in 2011 confirmed that the main bridge was a dangerous structure needing immediate strengthening.To ensure the operation safety of the bridge before the strengthening,the safety condition of the bridge was monitored.The calculation models of the bridge were established,and the models were modified by a series of measured data,including the physical and mechanical strength of the materials,hanger forces,tensile strength of the main cables and the corrosive ratio of the members of the steel structure.The load bearing performance was checked under the combined loading condition of dead load,vehicles with a loading capacity of 15 tand pedestrian loads,to find out the members in the most unfavorable loading state.During the safety monitoring,sensors were installed on the 22 members bearing bigger stresses,and the critical cross-sections,like the L/2,L/4,L/8 and the supports,were selected for vertical deformation monitoring.Based on the checking results of the load bearing capacity of the bridge as well as the allowable stress method,the warning stress values of the members monitored and the warning deflection values of the side spans and the middle span were determined.The results show that the calculation models modified can accurately simulate the real load bearing condition of the structure.The monitoring parameters and the warning values selected were proper.The stress increment of each member in the monitoring period did not surpass the warning values.The maximum deflection increment of each testing point was not bigger than 2 mm,less than the warning value,and the structure was in safe condition.
引文
[1]李爱群,缪长青.桥梁结构健康监测[M].北京:人民交通出版社,2009.
[2]苏成,廖威,袁昆,等.桥梁健康监测在线预警指标研究[J].桥梁建设,2015,45(3):44-50.
[3]孙增寿,李晓鹏,韩培琰.基于小波分析和移动荷载动力响应的连续梁损伤识别研究[J].世界桥梁,2017,45(1):33-38.
[4]李若涛,刘毅.拱形钢桥塔斜拉桥结构健康监测与评估研究[J].世界桥梁,2018,46(6):88-92.
[5]杨柏林,林超.宁安铁路安庆长江大桥长期监测方案设计研究[J].铁道标准设计,2017(2):68-73.
[6]闫志刚,岳青,施洲.沪通长江大桥健康监测系统设计[J].桥梁建设,2017,47(4):7-12.
[7]荆国强,王波,柴小鹏,等.高速铁路桥梁动力响应监测数据分析方法及其应用[J].桥梁建设,2018,48(2):31-36.
[8]JTJ 021-89,公路桥涵设计通用规范[S].
[9]张启伟.大型桥梁健康监测概念与监测系统设计[J].同济大学学报(自然科学版),2001(1):65-69.
[10]杨仕力,施洲.我国大跨径钢箱梁桥正交异性板疲劳损伤研究现状[J].桥梁建设,2017,47(4):60-65.
[2]苏成,廖威,袁昆,等.桥梁健康监测在线预警指标研究[J].桥梁建设,2015,45(3):44-50.
[3]孙增寿,李晓鹏,韩培琰.基于小波分析和移动荷载动力响应的连续梁损伤识别研究[J].世界桥梁,2017,45(1):33-38.
[4]李若涛,刘毅.拱形钢桥塔斜拉桥结构健康监测与评估研究[J].世界桥梁,2018,46(6):88-92.
[5]杨柏林,林超.宁安铁路安庆长江大桥长期监测方案设计研究[J].铁道标准设计,2017(2):68-73.
[6]闫志刚,岳青,施洲.沪通长江大桥健康监测系统设计[J].桥梁建设,2017,47(4):7-12.
[7]荆国强,王波,柴小鹏,等.高速铁路桥梁动力响应监测数据分析方法及其应用[J].桥梁建设,2018,48(2):31-36.
[8]JTJ 021-89,公路桥涵设计通用规范[S].
[9]张启伟.大型桥梁健康监测概念与监测系统设计[J].同济大学学报(自然科学版),2001(1):65-69.
[10]杨仕力,施洲.我国大跨径钢箱梁桥正交异性板疲劳损伤研究现状[J].桥梁建设,2017,47(4):60-65.