本文選題：大跨度斜拉橋　切入點：斷索事故　出處：《武漢理工大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：改革開放以后,我國經(jīng)濟(jì)總量逐年攀升,同時我國公路交通行業(yè)也得到了迅猛發(fā)展。其中常用于跨海、跨河地區(qū)的斜拉橋的發(fā)展對我國公路交通行業(yè)的發(fā)展做出了較大的貢獻(xiàn)。近三十年,斜拉橋因其獨特優(yōu)美的造型以及良好的跨越能力等特點,在我國得到了迅速推廣。大跨徑斜拉橋?qū)儆诙啻纬o定結(jié)構(gòu)體系,而且對其施加常規(guī)荷載,斜拉橋同樣將出現(xiàn)很大的位移,斜拉橋結(jié)構(gòu)的幾何位置也將會出現(xiàn)明顯的改變,結(jié)構(gòu)體系的受力特點表現(xiàn)為柔性結(jié)構(gòu)體系,即體現(xiàn)斜拉橋具有顯著的幾何非線性行為。本文以某大跨度斜拉橋在施工階段出現(xiàn)的斷索事故為工程背景,采用通用有限元軟件Abaqus對其斷索過程以及恢復(fù)過程進(jìn)行相應(yīng)簡化的幾何非線性分析,同時因斷索后混凝土出現(xiàn)大范圍開裂,所以在以上分析的同時還涉及相應(yīng)的混凝土材料非線性的分析研究。通過以上計算分析,論述了此斜拉橋斷索事故后的力學(xué)狀態(tài),并且驗證了張拉臨時索的恢復(fù)過程的恢復(fù)效果。通過數(shù)值模擬發(fā)現(xiàn),大里程方向左側(cè)13、15~22號斜拉索斷裂后,大里程方向的斜拉索的索力提升較大,而且左側(cè)的遠(yuǎn)墩柱端的斜拉索有拉斷的趨勢;大里程方向主梁出現(xiàn)大幅度的下沉,大里程方向12~16號梁段出現(xiàn)較為嚴(yán)重的扭轉(zhuǎn),從而主梁左側(cè)下沉更大,同時扭轉(zhuǎn)引起了此區(qū)域的混凝土出現(xiàn)大面積的受拉脆性開裂;主塔呈現(xiàn)逆時針的轉(zhuǎn)動(從上往下看)。臨時張拉斜拉索搶險后,斜拉橋已基本脫離了危險狀態(tài),斜拉索的索力、主梁線型、主塔偏位等均得到了大幅度的恢復(fù)。臨時索的索力完全恢復(fù)后,其內(nèi)力即變形相比斷索前的成橋狀態(tài)仍有差異,但差異較小,斜拉索的索力、主梁線型、主塔偏位等均得到了進(jìn)一步的恢復(fù)。通過計算與實測結(jié)果的對比分析發(fā)現(xiàn),斷索后的計算結(jié)果與實測結(jié)果很接近,而恢復(fù)過程的計算結(jié)果與實測結(jié)果具有不可忽略的差異,主要因為本文是采用混凝土的塑性損傷來模擬混凝土的實際脆性開裂,反向加載時模型的塑性變形不能恢復(fù),而實際的裂紋是可以閉合的。所以計算的恢復(fù)過程的斜拉橋的狀態(tài)與實際狀態(tài)之間存在差異。
[Abstract]:Since the reform and opening up, the total economic volume of our country has been rising year by year, at the same time, the highway transportation industry of our country has also been developed rapidly, which is often used to cross the sea. The development of cable-stayed bridges across rivers has made a great contribution to the development of highway transportation industry in China. In the last 30 years, cable-stayed bridges have been characterized by their unique beautiful shape and good span ability. The long-span cable-stayed bridge belongs to the statically indeterminate structure system for many times, and when it is subjected to conventional load, the cable-stayed bridge will also have a very large displacement, and the geometric position of the cable-stayed bridge will also be changed obviously. The structural system is characterized by flexible structural system, that is, the cable-stayed bridge has significant geometric nonlinear behavior. In this paper, the cable breaking accident of a long-span cable-stayed bridge in the construction stage is taken as the engineering background. The finite element software Abaqus is used to analyze the geometric nonlinearity of the cable breaking process and recovery process. At the same time, the concrete cracks on a large scale after cable break. Therefore, the above analysis also involves the nonlinear analysis of concrete materials. Through the above calculation and analysis, the mechanical state of the cable-stayed bridge after the cable breaking accident is discussed. Through numerical simulation, it is found that the cable force in the direction of large mileage is higher after the rupture of the cable 131522 on the left side in the direction of large mileage, and the effect of the restoration process of the tensioned temporary cable is verified. Moreover, the cable at the left end of the far pier column tends to be broken, the main girder in the direction of large mileage is sinking by a large margin, and the section of beam 1216 in the direction of long mileage has a more serious torsion, thus the left side of the main beam is sinking even more. At the same time, the torsion caused a large area of tensile brittle cracking of concrete in this area, and the main tower turned counterclockwise (from the top down). After the emergency of the temporary tensioning cable, the cable stayed bridge was basically out of the dangerous state, and the cable force of the cable stayed, After the cable force of the temporary cable is completely restored, the internal force, that is, the deformation of the temporary cable, is still different from the bridge state before the cable break, but the difference is small, the cable force of the stay cable, the line type of the main beam, and so on. The comparison and analysis between the calculated results and the measured results show that the calculated results are very close to the measured ones, while the results of the restoration process are not negligible. The main reason is that the plastic damage of concrete is used to simulate the actual brittle cracking of concrete, and the plastic deformation of the model can not be restored under reverse loading. The actual cracks can be closed, so there is a difference between the calculated state of the cable-stayed bridge and the actual state.
【學(xué)位授予單位】：武漢理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：U448.27

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 陳明憲;;斜拉橋的發(fā)展與展望[J];中外公路;2006年04期

2 經(jīng)柏林;斜拉橋的現(xiàn)狀與展望[J];中國市政工程;2002年01期

3 閭開軍,孫江濤,胡曉東;淺談斜拉橋的發(fā)展[J];湖南交通科技;1999年01期

4 陳務(wù)軍,關(guān)富玲,袁行飛,陳向陽;斜拉橋施工控制分析中線性與非線性影響分析[J];中國公路學(xué)報;1998年02期

5 樓莊鴻;斜拉橋的界限[J];國外公路;1997年05期

6 梁碩,曾慶元,張起森;大跨度混凝土斜拉橋極限承載力分析綜述[J];長沙交通學(xué)院學(xué)報;1997年03期

7 蔡國宏;斜拉橋的發(fā)展經(jīng)驗和展望[J];國外公路;1997年04期

8 周先雁，，程翔云;斜拉橋施工階段主梁縱向面內(nèi)穩(wěn)定性試驗研究[J];中國公路學(xué)報;1994年04期

9 潘家英,吳亮明,高路彬;大跨度斜拉橋活載非線性研究[J];土木工程學(xué)報;1993年01期

10 陳政清,曾慶元,顏全勝;空間桿系結(jié)構(gòu)大撓度問題內(nèi)力分析的UL列式法[J];土木工程學(xué)報;1992年05期

本文編號：1616977