摘要
针对单一可靠性方法精度不足的缺点,提出了概率-模糊-非概率混合可靠性模型。以桥式起重机桥架结构为研究对象,根据起重机结构不同变量的特点,采用不同的可靠性理论进行建模,使结果更接近于结构实际安全状态。采用基于凸集合的非概率可靠性模型,在小样本数据情况下,得到相关不确定性参数的上下界,通过将混合可靠性理论应用于起重机主梁结构可靠性的求解,得到其非概率模型可靠性,进而考虑材料边界条件的随机性与模糊性求得混合模型可靠度。当材料的许用应力服从正态隶属函数时,混合模型可靠度一般比凸集合非概率模型可靠度要略小,混合模型可靠度往往比凸集合非概率模型可靠度略显保守。当混合模型可靠度大于凸集合非概率模型可靠度时,混合模型可靠性计算就失去了意义。本方法可弥补起重机桥架结构可靠性分析时因试验经费少而缺乏大量试验数据的不足。
The present paper is aimed to propose a probabilisticfuzzy and non-probabilistic hybrid reliability model to assess and determine the non-probabilistic reliability based on the crane metallic structure design theory characteristic features of the miniature sample reliability data of the crane bridge structure. All of the said theoretical and material data are to be done in accordance with the non-probabilistic convex set theory and its nonprobabilistic reliability of the main crane structure. On the other hand,the safety performance of the crane has to be dependent on the main bearing parts of the bridge crane and their reliability.That is why the paper intends to build up and obtain a structural mixed reliability model based on the randomness and ambiguity of the variables according to the compatibility basis. And,then,the reliability comparison between the convex and the convex non-probabilistic model should be able to validate the rationality and dependability of the hybrid reliability model. Taking the bridge structure of the overhead crane as the research sample,according to the features of the different variables of the crane steel structure,it is necessary to apply the reliability theory to testing the reliability model based on the actual safety state of the crane structure. Such a kind of non-probabilistic reliability model based on the convex sets has to be employed thanks to its small number of sampling data. For,the hybrid reliability theory can help to obtain the upper and lower bounds of the uncertain parameters. And,furthermore,the reliability of the non-probabilistic model can be gained for the reliability of the structure of the crane girder on account of the randomness and fuzziness of the material boundary solidness condition. And,since the allowable stress of the materials should be decided by the normal membership function,the reliability of the mixed model is allowed to be generally slightly lower than that of the convex set non-probabilistic model. Besides,since the reliability of the hybri
作者
刘丽
杨瑞刚
LIU Li;YANG Rui-gang(Department of Mining Engineering,Lüliang College,Luliang 033001,Shanxi,China;College of Mechanical Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2020年第5期1758-1764,共7页
Journal of Safety and Environment
基金
山西省回国留学人员科研资助项目(2015-088)
山西省留学人员科技活动项目择优资助项目。
关键词
安全工程
桥式起重机结构
混合可靠性模型
结构可靠性分析
safety engineering
overhead crane structure
hybrid reliability model
structural reliability analysis
