本文選題：車橋耦合　切入點：吊桿體系　出處：《大連海事大學》2017年博士論文

【摘要】：拱橋結(jié)構(gòu)在當代橋梁建設(shè)中得到越來越多的應(yīng)用,這一橋型的安全性和耐久性問題也日益突出,其中,在中下承式拱橋中以吊桿體系的問題最為顯著。近年來發(fā)生的多起拱橋坍塌事故,大多是由于吊桿體系發(fā)生破壞所導致。研究發(fā)現(xiàn),在大量的吊桿體系破壞實例中,常常是以短吊桿失效為主,或短吊桿首先發(fā)生失效。影響吊桿體系耐久性的原因是多方面的,如腐蝕、疲勞等因素。一般地,可以認為同一拱橋上各吊桿所處的自然環(huán)境是相同的,長短吊桿之間這種耐久性上的差異,主要是由于車輛荷載產(chǎn)生的動力效應(yīng)不同而導致。因此,有必要通過詳盡的分析,研究拱橋吊桿體系的安全及耐久性問題。本文在考慮車橋動力耦合的基礎(chǔ)上,分析了吊桿體系尤其是短吊桿易于破壞的機理,深入研究了提高吊桿體系耐久性及保障吊桿體系安全性的設(shè)計方法。主要內(nèi)容如下:首先,建立車橋耦合動力分析模型。分別建立了大跨度拱橋三維有限元結(jié)構(gòu)模型、空間多軸車輛模型和路面不平度模型并由三個模型組成車橋耦合動力分析模型,進行車橋耦合分析。通過橋梁靜動態(tài)響應(yīng)的計算結(jié)果與橋梁荷載試驗實測結(jié)果的比較,驗證了所建立的拱橋動力分析模型,保證了模型的可行性。其次,基于所建立的考慮車橋耦合的動力分析模型,對吊桿體系的動力響應(yīng)進行分析。通過對吊桿應(yīng)力沖擊效應(yīng)、彎曲效應(yīng)的計算分析,研究了不同車速、車重、路面不平度以及車輛加速度對吊桿動力響應(yīng)的影響。研究表明,車輛荷載對吊桿體系產(chǎn)生顯著的沖擊效應(yīng)和彎曲效應(yīng),進而在吊桿截面產(chǎn)生較大的應(yīng)力變幅和明顯的不均勻應(yīng)力分布,使吊桿體系易于疲勞破壞。短吊桿截面應(yīng)力水平高于長吊桿,受沖擊作用更為顯著,因而更易疲勞破壞。然后,基于本文所揭示的短吊桿更易疲勞破壞的工作機理,提出了吊桿體系的等剛度模型來提高吊桿體系的耐久性。通過調(diào)整吊桿體系軸向剛度來改善短吊桿在車輛荷載作用下的受力條件,提高短吊桿的抗沖擊性能,延長短吊桿使用壽命,進而提高整個吊桿體系的耐久性。同時,基于實際監(jiān)測車流統(tǒng)計模型所建立的車速車重聯(lián)合分布模型,建立車流荷載并通過車流加載分析,對等剛度模型中吊桿體系的耐久性進行了評估。最后,針對吊桿體系失效難以預(yù)測的問題,通過增設(shè)預(yù)警吊桿,提出了具有預(yù)警與破損安全功能的新型雙吊桿體系模型�；谠撃Ｐ�,探討了面向疲勞壽命的體系設(shè)計方法。通過使用壽命設(shè)計使吊桿體系具備以下性能:(1)預(yù)警吊桿與工作吊桿具有經(jīng)濟合理的疲勞壽命差;(2)預(yù)警吊桿破損時,保證工作吊桿的安全和整體結(jié)構(gòu)形態(tài)正常。從而提高了吊桿體系安全運營的可靠性。通過調(diào)整預(yù)警吊桿初始應(yīng)力來實現(xiàn)與工作吊桿之間的疲勞壽命差異。通過車流加載進行疲勞壽命分析,對預(yù)警功能進行了評價。在此基礎(chǔ)上研究了吊桿體系損傷程度對疲勞壽命差異的影響,進一步評價了該吊桿體系模型的預(yù)警與破損安全性能。
[Abstract]:The arch structure is used more and more widely in the modern bridge construction, the bridge safety and durability problems have become increasingly prominent, which, in the lower arch bridge in the boom system problems are most significant. Many bridge collapse in recent years, mostly caused by the failure in the boom system study found that, in a large number of suspender system failure examples, often with short suspender failure, or failure reasons. First, short suspenders suspender system durability influence is in many aspects, such as corrosion, fatigue and other factors. In general, can be considered at the same arch bridge suspender's natural environment is the same, the durability of the difference between the length of the boom, is mainly due to the different dynamic effect of vehicle load have caused. Therefore, it is necessary through the detailed analysis of the security and durability of the arch bridge suspender system The problem. Considering the dynamic coupling on the analysis of the mechanism of short suspenders suspender system especially easy to destroy, in-depth study to improve the design method of suspender system durability and security suspender system security. The main contents are as follows: firstly, build a vehicle bridge coupling dynamic analysis model. The three-dimensional finite long span arch bridge element structure models are established, the multi axis vehicle space model and road roughness model and consist of three models of vehicle bridge coupling dynamic analysis model, coupled analysis. Through comparison of test results and the dynamic response of the bridge of Liang Jing bridge load test results, verify the dynamic analysis model of arch bridge is established, the model of the feasibility. Secondly, considering the dynamic analysis model of vehicle bridge coupling based on the dynamic response of the system, on the analysis of the impact stress of derrick Effect analysis and calculation of the bending effect of different speed, weight, and influence of road roughness and vehicle acceleration on the dynamic response of the boom. The study shows that the impact of vehicle load effect and the bending effect of suspender system, resulting in high stress amplitude and obviously uneven stress distribution in the cross section. The crane system is easy to fatigue damage. The short section of the stress level is higher than the long boom boom, the impact is more significant, so it is more easy to fatigue failure. Then, the working mechanism of short suspenders disclosed more easily fatigue failure based on the proposed boom system such as the stiffness model to improve the durability of the boom system. By adjusting the axial stiffness of the suspender system to improve the short suspenders under vehicle load stress condition, improve the anti shock performance of short suspenders, prolong the service life of short suspenders, and improve the whole The durability of the suspender system. At the same time, based on the actual monitoring of traffic statistics model of speed weight joint distribution model, the establishment of traffic load and traffic load through the analysis, the durability of the equivalence rigidity model of suspender system is evaluated. Finally, aiming at the failure of the suspender system is difficult to predict, by adding a warning boom, put forward a new type of double suspender system model of early warning and fail safe function. Based on this model, discusses the system design method for fatigue life. By using the life design of the suspender system have the following properties: (1) early warning and work with the fatigue life of derrick boom economic reasonable difference; (2) early warning of Suspender Damage, guarantee safety and overall structure work properly. Suspender improves reliability of suspender system safe operation. By adjusting the initial boom stress to achieve early warning and lifting The difference between rod fatigue life. The fatigue life is analyzed by using the traffic load, the warning function were evaluated. On the basis of the research on influence of suspender system damage on the fatigue life of the difference, further evaluation of the boom system model of early warning and safety can be damaged.

【學位授予單位】：大連海事大學
【學位級別】：博士
【學位授予年份】：2017
【分類號】：U448.22

【相似文獻】

相關(guān)博士學位論文 前1條

1 邵元;考慮車橋耦合的拱橋吊桿體系安全及耐久性研究[D];大連海事大學;2017年

相關(guān)碩士學位論文 前4條

1 杜朋;鋼管混凝土拱橋吊桿更換技術(shù)研究[D];長安大學;2017年

2 段惠濤;中下承式拱橋吊桿破斷動力響應(yīng)分析[D];鄭州大學;2017年

3 舒康;鋼管混凝土拱橋施工監(jiān)控及吊桿張力控制[D];煙臺大學;2017年

4 秦煥城;異型梁拱組合橋參數(shù)敏感性分析[D];鄭州大學;2017年

，

本文編號：1720546