摘要
针对高速公路改扩建工程中既有桥梁是否能继续使用问题,综合考虑总体技术状况、承载力状况、剩余耐久年限状况3个层次,创建了以桥梁构件类别的外观耐久状态为一级指标、以剩余耐久年限为二级指标的评判方法,提出了表征构件剩余耐久年限的寿命系数和可用寿命系数,建立了既有桥梁的延寿准则和延寿策略,探讨了可用寿命系数与目标使用年限、单次延寿的有效保护年限、拟采取的维护措施类型数量的相互关系。以京沪高速改扩建工程为研究背景,选取9座既有桥梁为典型桥梁,按100 a目标使用年限,计算得到构件主筋和箍筋的剩余耐久年限,给出了典型桥梁主体构件剩余耐久年限。根据可用评判方法,计算得到了在相同延寿措施下的延寿年限、延寿费用及可用寿命系数,按经济最优原则提出了从A级到E级共计5种延寿方式。研究表明,京沪高速改扩建工程典型桥梁按箍筋计算得到构件耐久寿命比按主筋计算值低,建议构件年限按箍筋计算值取用;目标使用年限为100 a时,主梁构件可正常使用比例为94%,墩柱单元、盖梁单元、桥台单元的可正常使用比例分别为67%,11%,44%。实际工程表明,采用该评判方法的评判结果与结构实际状态基本相符,与工程实际采取的处置措施基本相当,验证了该方法的合理性。
Aiming at the problem of whether existing bridges in expressway reconstruction and expansion projects can remain in service,the evaluation method was established with the appearance durability of bridge components as the first-level indicator,and the remaining durability as the second-level indicator.The method took the overall technical condition,bearing capacity and remaining durability life status into consideration.The life coefficient and available life coefficient were proposed,which represented the remaining durable life of components.The life extension criteria and strategies for existing bridges were established.The relation among available life coefficient,target service life,effective protection life of single life extension and number of maintenance measures was discussed.Taking Beijing-Shanghai expressway reconstruction and expansion project as the study background,there were 9 existing bridges selected as the typical bridges.The remaining durability life of main reinforcement and stirrup was calculated according to the target service life of 100 years,and the remaining durability life of typical bridge was got.According to the available evaluation method,the life extension,life extension cost and available life coefficient with different life extension measures were calculated.There were 5 life extension methods from class A to class E put forward according to the economic optimization principle.The result indicates that the durability life according to stirrup is lower than that of main reinforcement,so it is recommended to use the life according to stirrup.When the target service life is 100 year,the serviceable ratio of main beam members is 94%.The serviceable ratios of pier column unit,cover beam unit and abutment unit are 67%,11%,44%respectively.The actual project shows that the evaluation result of the propsed method is basically consistent with the actual state of structure.It is basically equivalent to the actual disposal measures taken by the project,which verifies the method rationality.
作者
赵尚传
左新黛
王少鹏
ZHAO Shang-chuan;ZUO Xin-dai;WANG Shao-peng(Research Institute of Highway,Ministry of Transport,Beijing 100088,China)
出处
《公路交通科技》
CAS
CSCD
北大核心
2024年第9期132-140,共9页
Journal of Highway and Transportation Research and Development
基金
中央级公益性科研院所基本科研业务费项目(2017-9035)。
关键词
桥梁工程
延寿准则
评判方法
主体构件
耐久年限
改扩建
bridge engineering
life extension criteria
evaluation method
main component
durability
reconstruction and expansion
