本文選題：時變可靠性 + 概率方法　； 參考：《湖南大學》2014年碩士論文

【摘要】：結構的可靠性與機械產(chǎn)品質(zhì)量密切相關，近年來越來越受到重視。傳統(tǒng)的可靠性分析技術，通常在不考慮時變載荷和強度退化的精確模型下處理問題，因而得到的可靠度是一個不變的固定數(shù)值。然而實際工程問題往往很復雜：1、因材料退化及動態(tài)不確定性載荷等引起的時變特性廣泛存在；2、由于試驗條件和成本的限制，有些參數(shù)，例如強度衰減函數(shù)參數(shù)、初始抗力和動、靜載荷概率分布參數(shù)等，因試驗樣本不足無法得到精確值。因此，可靠性分析方法應夠充分考慮這些問題，以更好地滿足工程實際要求。基于上述想法，本文研究了機械結構時變可靠性分析方法，為產(chǎn)品在全生命周期內(nèi)的設計提供了分析工具。主要研究內(nèi)容如下： 1、針對概率分布參數(shù)中存在區(qū)間不確定性的混合不確定問題，構造了一種含區(qū)間變量的時變可靠性分析方法。該方法首先將含區(qū)間變量的時變可靠性分析模型轉換為一概率—區(qū)間混合靜態(tài)可靠性問題，并采用了一種高效序列迭代格式，最終獲得時變可靠度的上、下邊界。 2、針對非線性功能函數(shù)，提出了一種時變可靠性分析方法。該方法首先將時變功能函數(shù)中的隨機過程進行離散，獲得多個不同時間段的靜態(tài)功能函數(shù)，，通過將各功能函數(shù)在最大可能點(Most Probable Point, MPP)處進行線性化，并運用全概率公式將其化簡為一新的靜態(tài)可靠度分析模型，最終采用傳統(tǒng)的一次二階矩方法(First Order Reliability Method, FORM)進行高效求解。 3、針對功能函數(shù)非線性且存在任意隨機變量和隨機過程的可靠性分析問題，提出了一種基于過程離散的時變可靠度分析方法（TRPD）。通過時間離散，將隨機過程轉換為隨機變量，并將時變可靠性問題轉換為常規(guī)的時不變體系可靠性問題。通過FORM進行極限狀態(tài)方程的線性化，并引入一新的隨機變量，對轉換得到的體系可靠性問題進行高效求解。
[Abstract]:The reliability of structure is closely related to the quality of mechanical products, and has been paid more and more attention in recent years. The traditional reliability analysis technique usually deals with the problem without considering the time-varying load and the degradation of the strength, so the reliability obtained is an invariant fixed value. However, the practical engineering problems are often very complicated, and the time-varying characteristics caused by material degradation and dynamic uncertain loads are widespread. Due to the limitation of test conditions and costs, some parameters, such as the strength attenuation function parameters, are obtained. The initial resistance, dynamic and static load probability distribution parameters can not be obtained because of the shortage of test samples. Therefore, the reliability analysis method should fully consider these problems in order to better meet the practical requirements of engineering. Based on the above ideas, the time-varying reliability analysis method of mechanical structures is studied in this paper, which provides an analytical tool for product design in the whole life cycle. The main research contents are as follows: 1. A time-varying reliability analysis method with interval variables is proposed to solve the mixed uncertainty problem with interval uncertainty in the parameters of probability distribution. In this method, the time-varying reliability analysis model with interval variables is first transformed into a probabilistic and interval-mixed static reliability problem, and an efficient sequential iterative scheme is used to obtain the upper time-varying reliability. Second, a time-varying reliability analysis method is proposed for nonlinear functional functions. In this method, the random processes in the time-varying function are discretized, and the static function is obtained at different time intervals. By linearizing each function at the maximum possible point, the function can be linearized at the most likely point of most potential point (MPP). The whole probability formula is used to simplify it into a new static reliability analysis model. Finally, the first order Reliability method (FORM) is used to solve this problem efficiently. 3. For the reliability analysis problems of nonlinear functional functions with arbitrary random variables and stochastic processes, the first order Reliability method (FORM) is used to solve the problem. A time-varying reliability analysis method based on process discretization is presented in this paper. By time discretization, the stochastic process is transformed into a random variable, and the time-varying reliability problem is transformed into a conventional time-invariant system reliability problem. The limit state equation is linearized by form and a new random variable is introduced to solve the system reliability problem efficiently.
【學位授予單位】：湖南大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TB114.3

【參考文獻】

相關期刊論文 前8條

1 王新剛;張義民;王寶艷;;機械零部件的動態(tài)可靠性分析[J];兵工學報;2009年11期

2 歐進萍;多自由度體系的動力可靠性分析[J];地震工程與工程振動;1987年04期

3 官鳳嬌;韓旭;姜潮;;基于區(qū)間法的發(fā)動機曲軸不確定性優(yōu)化研究[J];工程力學;2008年09期

4 貢金鑫,趙國藩;考慮抗力隨時間變化的結構可靠度分析[J];建筑結構學報;1998年05期

5 王良國,胡德波;368Q型發(fā)動機曲軸疲勞強度有限元分析[J];內(nèi)燃機學報;2000年03期

6 姜潮;黃新萍;韓旭;白影春;;含區(qū)間不確定性的結構時變可靠度分析方法[J];機械工程學報;2013年10期

7 張義民;;機械動態(tài)與漸變可靠性理論與技術評述[J];機械工程學報;2013年20期

8 張宇貽,秦權;鋼筋混凝土橋梁構件的時變可靠度分析[J];清華大學學報(自然科學版);2001年12期

本文編號：2025111