结构振动的模糊可靠性分析  

Fuzzy reliability analysis of structure vibration

作　　者：周海浪[1] 曾庆元[2] 

机构地区：[1]中南大学交通运输学院,湖南长沙410075 [2]中南大学土木建筑学院,湖南长沙410075

出　　处：《中南工业大学学报》2003年第6期645-647,共3页Journal of Central South University of Technology(Natural Science)

摘　　要：利用随机有限元理论建立结构振动的概率有限元计算公式系统,得出结构固有频率的均值及其方差;根据模糊集合理论的基本原理,在结构振动的可靠性分析中引入共振失效的模糊定义,指出共振准则具有模糊性.在此基础上,提出共振区模糊子集的隶属函数的确定原则,给出了具体的确定方法.根据模糊事件发生概率的定义,导出了结构振动的模糊可靠性的计算公式,考虑到结构具有多阶固有频率,在进行结构振动可靠性分析时,结构应为串联系统,从而解决了结构动态问题的模糊可靠性问题.通过结构振动模糊可靠度的计算实例,验证了该法的有效性和可行性,并指出常规可靠性计算由于不考虑共振区域的模糊性而使计算结果偏大.The mean and square difference of structure natural frequency is obtained based on the stochastic FEM formulation of structure vibration . The fuzzy definition of resonant failure is used in the reliability analysis of structure vibration according to the basic principle of the fuzzy set theory ,and that the resonant criterion has fuzziness is pointed out. On the basis of it, the principle of determining the membership function of the resonant region fuzzy set is proposed and the detailed method is given. The method of how to calculate the fuzzy reliability of the structure vibration is put forward according to the definition of probability of the fuzzy event. The fact that the structure has several degrees of natural frequency should be taken into account, so the structure should be a contact system in the structure vibration reliability analysis. A calculating example of fuzzy reliability of structure vibration testifies the proposed method and principle effectively. The method of conventional reliability analysis is prone to risk because it doesn′t take the fuzziness of resonant region into account.

关 键 词：结构振动 共振 模糊性 可靠性 随机有限元 

分 类 号：TU311.2[建筑科学—结构工程]