本文關(guān)鍵詞： 可靠度 敏感性 抗滑穩(wěn)定 有限元 安全系數(shù)　出處：《西華大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：重力壩是我國水利工程建設(shè)中常見壩型之一�；炷林亓沃饕孔陨碇亓慨a(chǎn)生抗滑力,最常見的破壞方式之一是滑動(dòng)失穩(wěn),且破壞過程復(fù)雜。重力壩一旦滑動(dòng)失穩(wěn)會(huì)產(chǎn)生嚴(yán)重影響,并造成巨大的經(jīng)濟(jì)損失,因而大壩的安全穩(wěn)定即核算重力壩壩體的抗滑穩(wěn)定分析是重力壩設(shè)計(jì)的一項(xiàng)重要內(nèi)容。傳統(tǒng)安全系數(shù)法是抗滑穩(wěn)定核算的重要計(jì)算方法,然而它在作結(jié)構(gòu)設(shè)計(jì)時(shí)有其局限性和不科學(xué)性。它反映的是同一類型的某種受力狀態(tài)下結(jié)構(gòu)的安全度,但對不同類型結(jié)構(gòu)或不同受力狀態(tài)的同一結(jié)構(gòu)同一截面來說,即使使用同一安全系數(shù),也不能保證它們具有相同的安全度。其原因在于安全系數(shù)法忽略了客觀上存在的各種設(shè)計(jì)變量的不確定性,只是把這些不確定量用一個(gè)籠統(tǒng)的K值掩蓋起來。應(yīng)用可靠度原理進(jìn)行結(jié)構(gòu)設(shè)計(jì)和校核,則可克服傳統(tǒng)方法的不足之處�？煽慷壤碚摮姓J(rèn)幾乎所有的工程變量均為隨機(jī)變量,以結(jié)構(gòu)安全性與可靠性的各種量值(可靠度、可靠性指標(biāo))來設(shè)計(jì)或校核結(jié)構(gòu),并能通過靈敏度的計(jì)算獲知各隨機(jī)變量對結(jié)構(gòu)安全影響的敏感程度,具有很好的應(yīng)用前景。本文結(jié)合重力壩穩(wěn)定開展可靠度計(jì)算和可靠度敏感性分析。首先,介紹了結(jié)構(gòu)可靠度的基本原理,建立了適應(yīng)于重力壩抗滑穩(wěn)定的極限方程,得出了敏感度計(jì)算公式。接著,利用有限元軟件建立了某水電站重力壩典型斷面的有限元模型,分別計(jì)算出在三種不同工況下該重力壩的安全系數(shù),分析其位移、有效應(yīng)力和等效應(yīng)力的分布規(guī)律,結(jié)合這三種工況下的可靠度核算結(jié)果評價(jià)該重力壩的整體安全度。然后,對影響該重力壩抗滑穩(wěn)定的可靠度靈敏性的主要因素進(jìn)行敏感性分析,評價(jià)各影響因素對可靠度的影響。最后對本文的研究進(jìn)行總結(jié)和展望。
[Abstract]:Gravity dam is one of the common dam types in water conservancy construction in China. Concrete gravity dam mainly relies on its own weight to produce anti-slide force, and one of the most common failure modes is sliding instability. And the failure process is complicated. Once the gravity dam slips out of stability, it will have a serious impact and cause huge economic losses. Therefore, the calculation of dam safety and stability is an important content of gravity dam design, and the traditional safety factor method is an important calculation method for calculation of anti-slide stability. However, it has its limitations and unscientific features in structural design. It reflects the safety degree of the same type of structure under a certain stress state, but for the same section of the same structure with different types of structures or different stress states, Even if the same safety factor is used, there is no guarantee that they have the same degree of safety. The reason is that the safety factor method ignores the uncertainty of the various design variables that exist objectively. By using the reliability principle to design and check the structure, the shortcomings of the traditional method can be overcome. The reliability theory recognizes that almost all engineering variables are random variables. The structural safety and reliability values (reliability, reliability index) are used to design or check the structure, and the sensitivity of each random variable to the structural safety can be obtained by calculating the sensitivity. In this paper, reliability calculation and reliability sensitivity analysis are carried out in combination with gravity dam stability. Firstly, the basic principle of structural reliability is introduced, and the limit equation suitable for gravity dam anti-slide stability is established. The sensitivity calculation formula is obtained. Then, the finite element model of typical section of gravity dam of a hydropower station is established by using finite element software, and the safety factor of the gravity dam under three different working conditions is calculated, and its displacement is analyzed. The distribution of effective stress and equivalent stress, combined with the results of reliability calculation under these three conditions, is used to evaluate the overall safety of the gravity dam. The main factors influencing the reliability sensitivity of the gravity dam are analyzed, and the influence of the factors on the reliability is evaluated. Finally, the research of this paper is summarized and prospected.
【學(xué)位授予單位】：西華大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TV642.3

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相關(guān)期刊論文 前1條

1 李美蓉;陳媛;張林;楊寶全;;復(fù)雜地質(zhì)條件下多結(jié)構(gòu)面對重力壩壩基穩(wěn)定性的影響及處理[J];巖土力學(xué);2014年S1期

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本文編號：1507520