發(fā)布時(shí)間：2018-03-18 20:36

  本文選題：橋梁工程　切入點(diǎn)：承載力評(píng)估　出處：《云南大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：在工程結(jié)構(gòu)中存在著不確定性,包括隨機(jī)性、模糊性和未確知性。而針對(duì)隨機(jī)性的概率可靠度理論在橋梁承載力評(píng)估過程中表現(xiàn)出的本質(zhì)上的不協(xié)調(diào)和不適應(yīng),因此本文擬對(duì)既有橋梁結(jié)構(gòu)評(píng)估的非概率時(shí)變可靠度進(jìn)行研究,提出對(duì)既有橋梁結(jié)構(gòu)進(jìn)行非概率可靠度評(píng)估的新技術(shù)。本文著重解決非概率可靠度理論在橋梁工程中所涉及到的根本問題,其主要研究內(nèi)容如下：(1)基于凸集的橢球模型結(jié)構(gòu)非概率可靠度計(jì)算的基本理論研究,得出基于凸集的橢球模型的相關(guān)數(shù)學(xué)表達(dá)式,分析該模型的適用條件和優(yōu)缺點(diǎn)。(2)基于區(qū)間運(yùn)算的可靠度分析,主要包括區(qū)間數(shù)的定義,區(qū)間的運(yùn)算格式,區(qū)間的獲取方法研究,以及常見結(jié)構(gòu)功能衰減參數(shù)的表達(dá)形式。然后研究基于橋梁的結(jié)構(gòu)抗力與荷載效應(yīng)的非概率可靠度指標(biāo)的具體求解方法。(3)結(jié)構(gòu)非概率可靠度評(píng)估體系研究,通過對(duì)基于實(shí)際檢測(cè)數(shù)據(jù)的非概率時(shí)變可靠度評(píng)定理論的研究,可以對(duì)影響現(xiàn)役鋼筋混凝土結(jié)構(gòu)橋梁抗力的諸多因素進(jìn)行分析,并研究在這些因素影響下的結(jié)構(gòu)性能退化機(jī)理和隨時(shí)間變化的數(shù)學(xué)模型,可得出在這些因素的綜合影響下結(jié)構(gòu)的時(shí)變抗力值。(4)對(duì)現(xiàn)役鋼筋混凝土拱橋的荷載效應(yīng)進(jìn)行分析,在同時(shí)考慮混凝土損失和鋼筋損傷及材料劣化的情況下,分析了矩形截面既有鋼筋混凝土構(gòu)件偏心受壓的時(shí)變計(jì)算模型,給出了時(shí)變抗力計(jì)算的簡化公式,針對(duì)其計(jì)算特點(diǎn),給出了判別大小偏心受壓的判斷條件。極大的簡化了橋梁評(píng)估的工作量和難度。本文將突破傳統(tǒng)橋梁承載力評(píng)定僅僅依賴概率可靠度理論的局面,使結(jié)構(gòu)的不確定性分析更為全面,有助于更加客觀真實(shí)地對(duì)橋梁結(jié)構(gòu)進(jìn)行綜合評(píng)定。
[Abstract]:There are uncertainties in engineering structures, including randomness, fuzziness and unascertained. Therefore, the non-probabilistic time-varying reliability of existing bridge structures is studied in this paper. A new technique for non-probabilistic reliability evaluation of existing bridge structures is proposed in this paper, which focuses on solving the fundamental problems involved in the theory of non-probabilistic reliability in bridge engineering. The main research contents are as follows: (1) the basic theory of non-probabilistic reliability calculation of ellipsoidal model structure based on convex set is studied, and the relevant mathematical expressions of ellipsoid model based on convex set are obtained. (2) based on the reliability analysis of interval operation, including the definition of interval number, the operation format of interval, the acquisition method of interval, the application conditions and advantages and disadvantages of the model are analyzed. Then, the non-probabilistic reliability evaluation system based on the bridge resistance and load effect is studied, which is based on the concrete solution method of non-probabilistic reliability index. By studying the theory of non-probabilistic time-varying reliability evaluation based on the actual test data, many factors affecting the resistance of existing reinforced concrete bridges can be analyzed. Under the influence of these factors, the mechanism of structural performance degradation and the mathematical model of the variation with time are studied. The time-varying resistance value of the structure under the influence of these factors is obtained. 4) the load effect of the active reinforced concrete arch bridge is analyzed. Considering the loss of concrete, damage of steel bar and deterioration of materials, the time-varying calculation model of eccentric compression of existing reinforced concrete members with rectangular section is analyzed, and a simplified formula for calculating time-varying resistance is given. The condition of judging the eccentric compression is given, which greatly simplifies the workload and difficulty of bridge evaluation. This paper will break through the situation that traditional bridge bearing capacity evaluation only depends on probabilistic reliability theory. It makes the uncertainty analysis of the structure more comprehensive and helps to evaluate the bridge structure more objectively and realistically.
【學(xué)位授予單位】：云南大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：U441

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 黃秀亮;王成剛;柳炳康;;再生混凝土抗碳化性能研究[J];合肥工業(yè)大學(xué)學(xué)報(bào)(自然科學(xué)版);2013年11期

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本文編號(hào)：1631226