拉索损伤对斜拉桥索力及主梁挠度变化的影响分析

发布时间：2018-06-05 17:48

本文选题：斜拉索 + 拉索锈蚀　；参考：《石家庄铁道大学》2015年硕士论文

【摘要】：随着服役时间的增长,斜拉索在使用过程中不可避免地会受到腐蚀退化、振动疲劳等不利因素的影响,从而导致拉索损伤。由于拉索的锈蚀损伤过程缓慢且不易察觉,故本文将拉索的锈蚀损伤作为研究重点。拉索锈蚀会引起拉索索力和主梁挠度发生变化,对斜拉桥的承载性能造成严重影响,直接影响着斜拉桥的正常运营,因此研究拉索损伤对索力及主梁挠度变化的影响有很大的实际意义和科研价值的。本文以芜湖长江大桥180 m+320 m+180 m矮塔斜拉桥为研究对象,依据其设计图纸,利用ANSYS建立该桥的有限元模型,并对模型索力及预拱度进行修正,使模型索力及线形与实桥数据一致,修正好的模型便为该桥的有限元基准模型。另外,通过ANSYS建立了一个独塔单索面斜拉桥的基准模型,分别用面积折减法、弹模折减法、反向荷载法以及实体模拟法四种方法模拟拉索的锈蚀,分析拉索锈蚀断丝后索力及主梁挠度的变化规律,从而得到拉索锈蚀的最佳表征形式;用实体模拟法对拉索锈蚀未断丝的情况进行了模拟,来分析不同拉索在不同锈蚀程度下索力及主梁挠度的变化规律。然后将上述得到的最佳表征方法运用于芜湖长江大桥斜拉桥的基准模型中,研究不同拉索锈蚀不同程度时拉索索力及主梁挠度的变化规律,并对该桥在不同的荷载作用下索力和挠度的变化进行了分析。将损伤效应与荷载效应两种情况进行对比,分析两者的区别。最后分析该桥拉索损伤后在不同荷载作用下拉索索力及主梁挠度的变化规律,研究荷载效应对损伤效应的放大作用,以便更准确地对拉索损伤进行识别。
[Abstract]:With the increase of service time, the cable will inevitably be affected by corrosion degradation, vibration fatigue and other adverse factors in the process of use, resulting in cable damage. Because the corrosion damage of cable is slow and difficult to detect, the corrosion damage of cable is considered as the focus in this paper. The corrosion of cable will cause the change of cable force and deflection of main beam, which will seriously affect the bearing capacity of cable-stayed bridge and directly affect the normal operation of cable-stayed bridge. Therefore, it is of great practical significance and scientific research value to study the influence of cable damage on cable force and deflection of main beam. This paper takes the 180 m 320 m 180 m low tower cable-stayed bridge of Wuhu Yangtze River Bridge as the research object, according to its design drawing, uses ANSYS to establish the finite element model of the bridge, and modifies the model cable force and pre-arch degree. The model cable force and line shape are consistent with the real bridge data, and the modified model is the finite element benchmark model of the bridge. In addition, a reference model of cable-stayed bridge with single tower and single cable plane is established by ANSYS. The corrosion of cable is simulated by area reduction method, elastic modulus reduction method, reverse load method and solid simulation method, respectively. The variation law of cable force and deflection of main beam after cable rust breaking is analyzed, and the best representation of cable corrosion is obtained. The case of cable corrosion without breaking is simulated by solid simulation method. To analyze the variation law of cable force and beam deflection under different corrosion degree. Then the optimal representation method is applied to the reference model of the cable-stayed bridge of Wuhu Yangtze River Bridge, and the variation law of cable force and deflection of main beam is studied with different degrees of cable corrosion. The variation of cable force and deflection of the bridge under different loads is analyzed. The damage effect and load effect are compared and the difference between them is analyzed. Finally, the variation law of the cable force and the deflection of the main beam after the cable damage is analyzed, and the amplification of the damage effect by the load effect is studied in order to identify the cable damage more accurately.
【学位授予单位】：石家庄铁道大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U448.27

【参考文献】