本文選題：鋼筋砼橋 + 承載力��； 參考：《長安大學(xué)》2014年碩士論文

【摘要】：鐵路被稱為國民經(jīng)濟(jì)的大動(dòng)脈，建國以來，我國鐵路事業(yè)取得了長足的進(jìn)步，鐵路橋梁屬于鐵路線路的大型永久建筑物，它構(gòu)造復(fù)雜、技術(shù)性強(qiáng)，建造工期久、價(jià)值比較高。為配合鐵路事業(yè)的發(fā)展，我國20世紀(jì)六七十年代起興建了一大批中小跨鋼筋混凝土簡支鐵路橋，目前這些橋梁大多正在服役或已退出工作。 對(duì)于正在服役的既有橋梁來說，由于長期受到列車動(dòng)荷載和風(fēng)吹雨淋、溫度變化等大氣環(huán)境的影響，其技術(shù)狀態(tài)不斷劣化，如不及時(shí)發(fā)現(xiàn)和預(yù)防，將會(huì)給橋梁的安全性帶來巨大的隱患。因此對(duì)既有橋梁承載力和動(dòng)力性能等進(jìn)行研究、檢測、評(píng)定，決定現(xiàn)有橋梁是繼續(xù)使用還是需要維修加固或改造，具有重要意義。 本文在總結(jié)前人的研究成果的基礎(chǔ)上，結(jié)合寶雞清姜河鐵路橋檢測項(xiàng)目，對(duì)現(xiàn)有鋼筋混凝土簡支梁橋進(jìn)行靜力荷載和動(dòng)力荷載試驗(yàn)，，并根據(jù)橋梁特點(diǎn)，選擇單片∏型梁建立適合實(shí)際情況的有限元模型。并針對(duì)清姜河鐵路橋提出了相應(yīng)的加固建議。具體內(nèi)容如下： 1、既有鋼筋混凝土橋梁性能評(píng)估方法 介紹了橋梁評(píng)估方法研究的現(xiàn)狀，說明了橋梁性能評(píng)估的流程與方法，指出對(duì)于既有鋼筋混凝土橋梁的評(píng)估，主要包括橋面系外觀檢測、混凝土性能檢測、鋼筋性能檢測等內(nèi)容。 2、工程實(shí)例分析 介紹了本次試驗(yàn)的工程背景，對(duì)橋梁外觀檢測的內(nèi)容及應(yīng)注意的問題做了說明，運(yùn)用內(nèi)燃機(jī)機(jī)車對(duì)橋梁進(jìn)行了靜載和動(dòng)載試驗(yàn)，得出了反映橋梁靜力性能和動(dòng)力性能的應(yīng)變、撓度、振幅、頻率、速度、加速度響應(yīng)實(shí)測數(shù)據(jù)，為有限元模型建立和制定相應(yīng)合理有效的加固措施提供試驗(yàn)依據(jù)。 3、橋梁有限元模型建立與分析 介紹了有限元軟件MIDAS/Civil及求解的基本原理與過程，建立了單片∏梁的有限元模型，并對(duì)橋梁的受力情況進(jìn)行模擬，利用跨中截面應(yīng)力、撓度的模擬值與實(shí)測對(duì)比，驗(yàn)證橋梁模型的有效性；對(duì)橋梁進(jìn)行了模態(tài)分析，得出縱橫豎三個(gè)方向的自振頻率和前8階振型；分析跨中撓度在不同車速作用下的變化規(guī)律，為同類橋梁的承載力與動(dòng)力性能分析提供參考。 4、鋼筋混凝土橋梁加固 結(jié)合寶橋的試驗(yàn)測試分析和有限元模擬分析結(jié)果，對(duì)混凝土表面及裂縫、橋面、橋墩、橋臺(tái)、走道板、護(hù)坡提出了幾點(diǎn)維修建議；為提高梁的抗剪能力并增強(qiáng)梁的整體性，同時(shí)為補(bǔ)足因銹蝕衰減的承載力，提出了主梁碳纖維布加固方案；為了增加主梁橫向剛度，對(duì)增加主梁橫隔板方案進(jìn)行探討。
[Abstract]:Railway is called the artery of national economy. Since the founding of our country, railway industry has made great progress. Railway bridge belongs to the large permanent building of railway line, which has complex structure, strong technology, long construction period and high value. In order to cooperate with the development of railway industry, a large number of small and medium span reinforced concrete simply supported railway bridges have been built in China since the 1960s and 1970s. At present, most of these bridges are in service or have retired from work. For the existing bridges in service, due to the influence of the atmospheric environment such as train dynamic load, wind and rain, temperature change for a long time, the technical status of the bridges is deteriorating continuously, such as not timely detection and prevention. It will bring great hidden danger to the safety of the bridge. Therefore, it is of great significance to study the bearing capacity and dynamic performance of existing bridges, to test, evaluate and decide whether the existing bridges should be maintained, strengthened or rebuilt. On the basis of summarizing the previous research results, combined with the inspection project of Qingjiang River railway bridge in Baoji, the static and dynamic load tests of the existing reinforced concrete simply supported beam bridge are carried out, and according to the characteristics of the bridge, A finite element model suitable for the actual situation is established by selecting a single piece of girder. Corresponding reinforcement suggestions are put forward for Qingjiang River railway bridge. The details are as follows: 1. Performance evaluation method of existing reinforced concrete bridges This paper introduces the research status of bridge evaluation methods, explains the flow and method of bridge performance evaluation, and points out that the evaluation of existing reinforced concrete bridges mainly includes the appearance detection of deck system and the testing of concrete performance. Steel bar performance testing and other content. 2. Engineering example analysis This paper introduces the engineering background of the test, explains the contents of the bridge appearance inspection and the problems needing attention. The static and dynamic load tests of the bridge are carried out by using the engine locomotive, and the strain reflecting the static and dynamic performance of the bridge is obtained. The measured data of deflection, amplitude, frequency, velocity and acceleration response provide experimental basis for the establishment of finite element model and the establishment of appropriate and effective reinforcement measures. 3. Establishment and analysis of bridge finite element model This paper introduces the basic principle and process of the finite element software MIDAS/Civil and its solution, establishes the finite element model of the single beam, and simulates the stress of the bridge. The stress and deflection of the mid-span section are compared with the measured values. The effectiveness of the bridge model is verified. The modal analysis of the bridge is carried out, and the natural vibration frequency and the first eight vibration modes in the three directions of vertical and vertical are obtained, and the variation law of the mid-span deflection under the action of different speed is analyzed. It provides a reference for the analysis of bearing capacity and dynamic performance of similar bridges. Reinforced concrete bridge reinforcement Combined with the results of test, test and finite element simulation of Baoqiao, some suggestions for maintenance of concrete surface and crack, bridge deck, pier, abutment, walkway board and slope protection are put forward in order to improve the shear resistance of the beam and enhance the integrity of the beam. At the same time, in order to supplement the bearing capacity of corrosion attenuation, the reinforcement scheme of main beam with carbon fiber sheet is put forward, and in order to increase the transverse stiffness of main beam, the scheme of increasing transverse partition board of main beam is discussed.
【學(xué)位授予單位】：長安大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：U448.13;U441

【參考文獻(xiàn)】

相關(guān)期刊論文 前6條

1 柳俊哲;呂麗華;李玉順;;混凝土碳化研究與進(jìn)展(2)——碳化速度的影響因素及碳化對(duì)混凝土品質(zhì)的影響[J];混凝土;2005年12期

2 李亞東;既有橋梁評(píng)估初探[J];橋梁建設(shè);1997年03期

3 李亞東;既有橋梁評(píng)估方法研究[J];鐵道學(xué)報(bào);1997年03期

4 袁萬城,崔飛,張啟偉;橋梁健康監(jiān)測與狀態(tài)評(píng)估的研究現(xiàn)狀與發(fā)展[J];同濟(jì)大學(xué)學(xué)報(bào)(自然科學(xué)版);1999年02期

5 戴松,禹智濤;某鋼筋混凝土橋梁檢測及病害分析[J];中南公路工程;2004年01期

6 曉宇;鐵路簡史(二)[J];交通與運(yùn)輸;2002年04期

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