本文選題：子集模擬 + 隨機(jī)結(jié)構(gòu)��； 參考：《大連理工大學(xué)》2014年碩士論文

【摘要】：結(jié)構(gòu)可靠性分析和優(yōu)化設(shè)計(jì)是國(guó)內(nèi)外工程力學(xué)界學(xué)者研究的兩個(gè)重要課題�？煽啃苑治鰧�(duì)結(jié)構(gòu)安全評(píng)定與服役壽命預(yù)測(cè)和正常運(yùn)行至關(guān)重要。結(jié)構(gòu)優(yōu)化設(shè)計(jì)可以使結(jié)構(gòu)的性能達(dá)到最佳,同時(shí)使資源得到合理利用,降低工程造價(jià)。子集模擬法是一種估計(jì)小概率失效問(wèn)題的可靠性分析方法,后來(lái)被推廣應(yīng)用到結(jié)構(gòu)優(yōu)化領(lǐng)域。本文借鑒子集模擬算法的馬爾科夫鏈概念改進(jìn)了基本的和聲搜索算法,建立了子集模擬和聲搜索算法,并研究了子集模擬方法在隨機(jī)結(jié)構(gòu)可靠性分析和結(jié)構(gòu)動(dòng)力優(yōu)化設(shè)計(jì)兩方面的應(yīng)用。具體內(nèi)容如下： 在工程實(shí)際中,外荷載和結(jié)構(gòu)參數(shù)通常具有隨機(jī)性。地震作用是典型的隨機(jī)荷載,時(shí)變隨機(jī)地震作用下結(jié)構(gòu)動(dòng)力可靠度的高效分析是一個(gè)富有挑戰(zhàn)性的問(wèn)題。子集模擬法作為一種效率較高的數(shù)字模擬方法為求解這類(lèi)問(wèn)題提供了有效工具。子集模擬法通過(guò)引入合理的較大失效概率的中間失效事件,將小失效概率轉(zhuǎn)化為一系列較大失效概率的乘積,對(duì)于這些較大失效概率可利用馬爾可夫鏈模擬高效估計(jì)條件樣本點(diǎn)來(lái)得到,從而提高計(jì)算效率。由隨機(jī)結(jié)構(gòu)動(dòng)力可靠度分析表明,子集模擬法大大減少了結(jié)構(gòu)重分析次數(shù),提高了計(jì)算效率。 而且,工程結(jié)構(gòu)不可避免地受到外界沖擊或振動(dòng)的干擾,為了確保工程結(jié)構(gòu)在動(dòng)荷載作用下能夠安全可靠地工作,需要進(jìn)行結(jié)構(gòu)動(dòng)力優(yōu)化設(shè)計(jì)。另一方面,子集模擬優(yōu)化算法是將優(yōu)化中的極值問(wèn)題巧妙地轉(zhuǎn)化為可靠性分析的小失效概率問(wèn)題。本文基于子集模擬優(yōu)化算法有效地解決了頻率約束下桁架的尺寸優(yōu)化和尺寸形狀優(yōu)化以及動(dòng)載荷作用下框架的尺寸優(yōu)化問(wèn)題,得到了優(yōu)化的結(jié)構(gòu)尺寸和形狀設(shè)計(jì)方案。 最后,針對(duì)基本和聲搜索不能獲得較高精度的解,易陷入局部最優(yōu)且效率不高的不足,借鑒了已有的參數(shù)和聲保留概率、音調(diào)調(diào)節(jié)概率和調(diào)節(jié)步長(zhǎng)的改進(jìn)措施,并結(jié)合子集模擬算法,提出了子集模擬和聲搜索混合優(yōu)化算法。由基準(zhǔn)數(shù)學(xué)算例和桁架結(jié)構(gòu)優(yōu)化實(shí)例表明,子集模擬和聲搜索混合算法具有較好的精確尋優(yōu)能力和魯棒性,能迅速收斂到最優(yōu)解,且對(duì)于多維優(yōu)化問(wèn)題,其計(jì)算性能表現(xiàn)良好。
[Abstract]:Structural reliability analysis and optimization design are two important topics studied by domestic and foreign engineering mechanics scholars. Reliability analysis is very important for structural safety assessment, service life prediction and normal operation. The optimum design of the structure can achieve the best performance of the structure, at the same time, the resources can be used reasonably, and the project cost can be reduced. Subset simulation is a reliability analysis method for estimating small probability failure problems, which has been extended to the field of structural optimization. In this paper, the basic harmonic search algorithm is improved by using the Markov chain concept of the subset simulation algorithm, and the subset simulation harmonic search algorithm is established. The application of subset simulation method in reliability analysis and dynamic optimization design of stochastic structures is also studied. The main contents are as follows: in engineering practice, external loads and structural parameters are usually random. Seismic action is a typical random load, and the efficient analysis of structural dynamic reliability under time-varying random earthquake is a challenging problem. As an efficient digital simulation method, subset simulation provides an effective tool for solving this kind of problems. By introducing a reasonable intermediate failure event with a high failure probability, the subset simulation method converts the small failure probability into the product of a series of larger failure probability. For these large failure probabilities, the Markov chain is used to simulate the efficient estimation of conditional sample points, thus improving the computational efficiency. The dynamic reliability analysis of random structures shows that the method of subset simulation greatly reduces the times of structural reanalysis and improves the efficiency of calculation. Moreover, the engineering structure is inevitably disturbed by external shock or vibration. In order to ensure that the engineering structure can work safely and reliably under the dynamic load, it is necessary to carry out structural dynamic optimization design. On the other hand, the subset simulation optimization algorithm is a small failure probability problem which transforms the optimization extremum problem into the reliability analysis problem. Based on the subset simulation optimization algorithm, the optimization of the size and shape of truss under frequency constraints and the optimization of frame size under dynamic load are effectively solved in this paper, and the optimal design scheme of structure size and shape is obtained. Finally, aiming at the deficiency that the basic harmonic search can not get a higher precision solution and is prone to fall into the local optimum and low efficiency, the improved measures of parameter and sound retention probability, tone adjustment probability and adjusting step size are used for reference. Combined with subset simulation algorithm, a subset simulation and acoustic search hybrid optimization algorithm is proposed. The examples of benchmark mathematics and truss structure optimization show that the hybrid algorithm of subset simulation and acoustic search has good accuracy and robustness, and can converge to the optimal solution quickly, and the performance of the hybrid algorithm is good for multidimensional optimization problems.
【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類(lèi)號(hào)】：TB114.3;TB12

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 劉佩;姚謙峰;;基于概率簡(jiǎn)單疊加法則的動(dòng)力可靠度高效計(jì)算方法[J];工程力學(xué);2010年04期

2 錢(qián)令希,鐘萬(wàn)勰,程耿東,隋允康;工程結(jié)構(gòu)優(yōu)化的序列二次規(guī)劃[J];固體力學(xué)學(xué)報(bào);1983年04期

3 彭細(xì)榮;隋允康;;有頻率禁區(qū)的連續(xù)體結(jié)構(gòu)拓?fù)鋬?yōu)化[J];固體力學(xué)學(xué)報(bào);2007年02期

4 王恒棟，，趙國(guó)藩;舊有結(jié)構(gòu)的神經(jīng)網(wǎng)絡(luò)評(píng)估[J];工業(yè)建筑;1996年08期

5 徐瑞;張加興;蘇成;;非平穩(wěn)隨機(jī)激勵(lì)下結(jié)構(gòu)動(dòng)力可靠度時(shí)域顯式子集模擬法[J];工程力學(xué);2013年07期

6 劉成立;呂震宙;;結(jié)構(gòu)可靠性分析中考慮高次項(xiàng)修正的組合響應(yīng)面法[J];航空學(xué)報(bào);2006年04期

7 金偉良;唐純喜;陳進(jìn);;基于SVM的結(jié)構(gòu)可靠度分析響應(yīng)面方法[J];計(jì)算力學(xué)學(xué)報(bào);2007年06期

8 顧松年,徐斌,榮見(jiàn)華,姜節(jié)勝;結(jié)構(gòu)動(dòng)力學(xué)設(shè)計(jì)優(yōu)化方法的新進(jìn)展[J];機(jī)械強(qiáng)度;2005年02期

9 呂震宙;楊子政;;基于神經(jīng)網(wǎng)絡(luò)的可靠性分析新方法[J];機(jī)械強(qiáng)度;2006年05期

10 李兵,蔣慰孫;混沌優(yōu)化方法及其應(yīng)用[J];控制理論與應(yīng)用;1997年04期

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