本文關(guān)鍵詞： 懸索橋加勁梁 隨機車流 動力可靠度 疲勞可靠度 密集運行狀態(tài) 首超準則 等效疲勞應力　出處：《長沙理工大學》2014年博士論文　論文類型：學位論文

【摘要】：公路橋梁在運營期承受大量車輛荷載的反復作用,隨著車流量和載重量的增加,車載下既有橋梁在的安全問題日益突出。車流量、結(jié)構(gòu)參數(shù)和失效模式等諸多因素的不確定性致使橋梁在運營期的安全性不免為概率問題。大跨度懸索橋的柔性加勁梁在車載下易出現(xiàn)位移超限失效和構(gòu)造細節(jié)疲勞累積損傷失效,基于結(jié)構(gòu)動力可靠度與疲勞可靠度理論可分別評估上述兩種失效模式下的安全水平。本文結(jié)合國家“973”項目“特大跨橋梁安全性設計與評定的基礎(chǔ)理論研究(2015CB057700)”和國家自然科學基金項目“車輛超載與氯鹽侵蝕復合作用下鋼筋砼梁橋的疲勞時變可靠度分析(51378081)”,主要研究基于高速公路橋梁WIM(動態(tài)稱重)系統(tǒng)的隨機車流模型,以及隨機車流作用下懸索橋加勁梁的動力響應(位移和疲勞應力)的概率特征,圍繞結(jié)構(gòu)可靠度研究中的兩個失效準則(首超破壞和疲勞破壞)研究全橋整體模型中的加勁梁位移首超動力可靠度和加勁梁局部模型中的焊接細節(jié)疲勞可靠度。具體研究內(nèi)容有：(1)研究了基于WIM系統(tǒng)的隨機車流模擬方法。建立了某高速公路車流的車型、軸重、車距、車速和車道等參數(shù)的概率模型,在MATLAB的GUI平臺編制了隨機車流模擬軟件,分別生成了稀疏和密集運行狀態(tài)下的隨機車流樣本,預測了交通量增長系數(shù)。(2)為了準確和快速得出車流荷載下大跨橋梁動力響應時程數(shù)據(jù),提出了基于有限元的簡化分析方法。以ANSYS通用有限元程序為平臺,充分發(fā)揮其對車輛和橋梁的簡化模擬能力以及瞬態(tài)分析的后處理功能,相關(guān)算例表明了該方法的可行性和準確性。(3)基于跨越理論建立了隨機車流作用下懸索橋加勁梁的位移響應的極值概率模型。研究了車輛和車流參數(shù)對車載下懸索橋加勁梁位移響應的影響,統(tǒng)計數(shù)據(jù)表明隨機車流下懸索橋位移響應為非嚴格高斯平穩(wěn)隨機過程,基于Rice公式預測了加勁梁在設計基準期內(nèi)的位移極值。(4)基于位移首超準則評估了隨機車流下懸索橋加勁梁的動力可靠度。討論了Possion假定和Markov假定對界限跨越率的影響,揭示了車輛運行狀態(tài)和加勁梁的參數(shù)變化對動力可靠指標的影響規(guī)律,參數(shù)分析表明主纜剛度退化和密集運行車輛是導致加勁梁位移首超失效的重要因素。(5)將典型疲勞車輛改進為隨機車流模型,結(jié)合高斯混合模型建立了運營期內(nèi)懸索橋鋼箱梁關(guān)鍵細節(jié)疲勞應力和疲勞損傷概率模型。針對隨機車流作用下有限分析的耗時過長問題,提出了基于UD-SVR(均勻設計-支向量回歸)聯(lián)合算法的隨機車流下鋼箱梁細節(jié)疲勞應力分析方法。(6)研究了考慮車流參數(shù)以及交通量和車重增長系數(shù)的鋼箱梁橋關(guān)鍵焊接細節(jié)疲勞可靠度。建立了考慮隨機車流參數(shù)的疲勞損傷功能函數(shù),編制了結(jié)構(gòu)疲勞可靠度分析軟件,分析了交通量和車重增長對不同車道處焊接細節(jié)疲勞可靠度的影響,基于目標可靠指標評估了鋼箱梁關(guān)鍵細節(jié)處疲勞性能。研究結(jié)果為基于車流輛監(jiān)測數(shù)據(jù)的橋梁焊接細節(jié)疲勞可靠度與加固維修提供了依據(jù)。
[Abstract]:Road bridge in the repeated operation period bear a large number of vehicle load, with the traffic and load increases, vehicle existing safety problems in bridge has become increasingly prominent. The traffic flow, structure parameters and failure mode of many factors such as the uncertainty of the bridge in the safety operation period is inevitably probability problem. The flexible beam the long-span suspension bridge in vehicle is prone to failure and displacement gauge structure detail fatigue cumulative damage failure, structure dynamic reliability and fatigue reliability theory respectively to assess the safety water above two failure modes. Based on the level of the basic theory research of bridge design and evaluation of security, combined with the national "973" project "(2015CB057700) and the National Natural Science Fund Project" fatigue of reinforced concrete beam bridge under the combined action of erosion overloading and chloride time-varying reliability analysis (51378081) "Based on the highway bridge WIM (WIM) random traffic flow model of the system, and the dynamic stiffened suspension bridge under random traffic flow beam response (displacement and fatigue stress) probability characteristics, around two criteria failure of structural reliability in (the first super damage and fatigue damage) of super dynamic reliability the degree of local model and stiffening girder welding in the details of the fatigue reliability of the stiffening girder displacement model of bridge in the whole song. The specific research contents are as follows: (1) to study the random traffic simulation method based on WIM system. The establishment of a certain expressway traffic flow models, axle load, vehicle distance, speed and lane, probability model the parameters in the MATLAB GUI platform, developed the random traffic simulation software, which generates sparse and dense running under the random traffic sample, forecasts the traffic volume growth coefficient (2). In order to accurately and quickly get out of the bus Flow load of long span bridge under dynamic response time history data, a simplified finite element analysis method. Based on the ANSYS finite element program as a platform, give full play to the function of vehicle and Bridge simplified simulation capability and transient analysis, relevant examples show the feasibility and accuracy of this method. (3) established the extreme probability model of displacement response of suspension bridges under random traffic flow across theory. Based on research of vehicle and traffic flow parameters on the stiffened suspension bridge under vehicle beam displacement response, the statistics show that the displacement response of suspension bridge under random traffic flow for non strict Gauss stationary stochastic process, the Rice formula for predicting the displacement the stiffening beam in the design reference period (4). Based on the displacement of the first super criterion based on the assessment of the random traffic flow dynamic stiffening girder of suspension bridge reliability is discussed. The assumption of Possion and Markov Assume the crossing rate impact on the boundaries, reveals the influence of parameter changing the running state of the vehicle and the stiffening girder on the dynamic reliability index, the parameter analysis indicates that the main cable stiffness degradation and intensive operation of the vehicle is an important factor leading to the displacement of stiffening girder first passage failure. (5) the typical vehicle fatigue improvement for the random traffic flow model. The establishment of the operation period of suspension bridge key details of fatigue stress and fatigue damage probability model with the Gauss mixture model. According to the random traffic flow under the limited analysis of the time consuming problem, proposed based on UD-SVR (uniform design - support vector regression) stress analysis method of fatigue of Steel Box Girder Joint Algorithm under random traffic details (6. Considering the traffic parameters) and bridge traffic volume and weight growth coefficient of the key welding detail fatigue reliability. A fatigue damage function considering random traffic parameters To function, developed the structure fatigue reliability analysis software, analyzed the influence of traffic volume and weight growth on different lanes at weld detail fatigue reliability, target reliability index evaluation based on the fatigue performance of steel box girder key details. The results for the bridge based on vehicle traffic monitoring data of the fatigue reliability of the welded details and provides reinforcement and maintenance on the basis of.

【學位授予單位】：長沙理工大學
【學位級別】：博士
【學位授予年份】：2014
【分類號】：U441;U448.25

【參考文獻】

相關(guān)期刊論文 前10條

1 徐日昶,路春和;林區(qū)橋梁動荷載沖擊系數(shù)的試驗研究[J];東北林業(yè)大學學報;1989年02期

2 陳建兵,李杰;隨機結(jié)構(gòu)復合隨機振動分析的概率密度演化方法[J];工程力學;2004年03期

3 張楠,夏禾;鐵路橋梁在高速列車作用下的動力響應分析[J];工程力學;2005年03期

4 郭薇薇;夏禾;徐幼麟;;風荷載作用下大跨度懸索橋的動力響應及列車運行安全分析[J];工程力學;2006年02期

5 李小珍;張黎明;張潔;;公路橋梁與車輛耦合振動研究現(xiàn)狀與發(fā)展趨勢[J];工程力學;2008年03期

6 張志超;張亞輝;林家浩;;車橋耦合系統(tǒng)非平穩(wěn)隨機振動分析的虛擬激勵-精細積分法[J];工程力學;2008年11期

7 王春生;馮亞成;;正交異性鋼橋面板的疲勞研究綜述[J];鋼結(jié)構(gòu);2009年09期

8 劉揚;魯乃唯;;鋼管混凝土組合高墩連續(xù)剛構(gòu)橋體系可靠指標計算方法[J];公路交通科技;2011年09期

9 王達;劉揚;韓萬水;黃平明;;公路橋梁隨機車流模擬研究[J];中外公路;2009年06期

10 潘春宇;童樂為;;鋼結(jié)構(gòu)疲勞可靠度設計方法的研究進展[J];鋼結(jié)構(gòu);2013年12期

相關(guān)博士學位論文 前3條

1 朱艷;車橋系統(tǒng)隨機振動理論與應用研究[D];西南交通大學;2011年

2 殷新鋒;汽車荷載作用下梁式橋與斜拉橋的動態(tài)響應分析[D];湖南大學;2010年

3 陳一馨;車輛載荷作用下鋼橋面板細部焊接結(jié)構(gòu)疲勞性能研究[D];長安大學;2013年

相關(guān)碩士學位論文 前3條

1 代偉;高速公路動態(tài)稱重系統(tǒng)關(guān)鍵問題的研究[D];長安大學;2008年

2 曾德亮;車橋耦合系統(tǒng)垂向隨機振動分析[D];西南交通大學;2012年

3 胡曉;隨機車流作用下大跨度斜拉橋振動響應分析[D];長沙理工大學;2013年

，

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