锈蚀檩条在台风作用下时变可靠度计算模型  

Time-dependent reliability calculation model of corroded purlin under typhoon hazard

作　　者：刘威 杨娜[1] 白凡[1] 翁凯 LIU Wei;YANG Na;BAI Fan;WENG Kai(School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China;Architectural Design and Research Institute,China Railway Design Corporation,Tianjin 300142,China)

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]中国铁路设计集团有限公司建筑设计研究院,天津30014211

出　　处：《北京交通大学学报》2019年第6期67-74,共8页JOURNAL OF BEIJING JIAOTONG UNIVERSITY

基　　金：国家重点研发计划（2018YFC0705600）;中国铁路总公司科技研究开发计划重点课题(2017G002-O)~~

摘　　要：基于大气锈蚀模型和简支檩条的屈曲计算理论,结合时变可靠度方法,提出了锈蚀檩条在台风作用下的可靠度计算模型.该模型考虑了在抗力层次锈蚀导致的抗力退化,以及在荷载层次台风的发生次数及强度.结合算例研究了中国沿海11个城市的锈蚀檩条可靠度变化规律,通过给出服役期间的可靠指标,进行可靠性分析.结果表明:锈蚀檩条在台风作用下的可靠指标在前5年下降速率较快,在第5年至服役期满逐渐趋于平缓.在服役前5年,锈蚀作用影响较小,但服役5年后直到服役期满,其对檩条可靠指标的影响逐渐增大.对比中美两国不同目标可靠指标下的评估结果,发现按照中国规范的评估结果较为保守.A reliability calculation model for the corroded purlin under typhoon hazard is proposed in this paper based on atmospheric corrosion model and the buckling calculation theory of simply supported purlin,combined with time-dependent reliability method.The proposed model takes the resistance degradation caused by corrosion at the resistance level and the frequency and intensity of typhoon at the load level into consideration.In this paper,the variation law of the reliability of corroded purlin in 11 coastal cities in China is studied.The reliability index during service is obtained,laying basis for reliability analysis of corroded purlin.The results show that under the typhoon hazard,the reliability index decrease rapidly in the first five years,and gradually become stable from the fifth year to the end of service.In the first 5 years of service,the effect of corrosion is low.However,the influence on the reliability index of purlin increases gradually from the fifth year to the end of service.The evaluation results under differing target reliability indexes of China and the United States are also compared.It is found that the evaluation results under the Chinese standard appear more conservative.

关 键 词：檩条 时变可靠度 锈蚀 台风 抗力退化 

分 类 号：TU391[建筑科学—结构工程] TU392.5