桥梁板桁组合结构体系载荷应力分布规律及其试验研究

发布时间：2018-05-19 17:33

本文选题：板桁结合结构 + 正交异性钢桥面板　；参考：《重庆交通大学》2014年硕士论文

【摘要】：板桁组合结构是由桥面板和桁架共同受力的结构，因为结构具有较好的综合高效性能而成为大多桥梁的选择，桥面板考虑正交异性钢桥面板高强度、自重轻、建筑高度低、结构连续、施工安装方便等特点而被采用，所以板桁结合结构成为世界上各大、中跨度桥梁的最佳选择。本文对在建的重庆市东水门长江大桥进行试验研究，重点对结构在斜拉索的作用下，，上层结构的桥面板、加劲肋、中纵梁及弦杆和横梁的顺桥向应力进行实测分析。运用Midas FEA进行有限元分析，同时根据材料的本构关系，详细分析结构模型在不同的荷载工况下各构件的应力分布；拉索产生的顺桥向力在各构件的分配比例；各构件对拉索水平分力的承担情况。同样对应桥梁的施工阶段进行实桥测试试验，给施工现场的各构件布设传感器，采集数据并把有限元计算的结果和实桥测试试验的结果进行对比分析，检验有限元分析的可靠性和准确性。论文研究结果表明，拉索作用下上层桥面各构件受压，随着与拉索距离的增加，分布逐渐均匀，应力值逐渐增大，拉索索孔后面的位置，桥面均为受拉，传递向后扩散，扩散角与X呈47度，直至上弦杆，应力沿顺桥向拉索前为压，拉索后为拉，其他上层构件应力状况与桥面板相似。9#索力下的应力值都有所增加，其主要原因是斜拉索的竖向分力对结构产生附加弯矩。最后，计算得到桥面板的分配比例趋于稳定整个节段分配比例的范围在28.21%～60.72%，为承担水平力最大的构件，所占的比例先减小后增大再减小最后趋于稳定，约占40%左右。桥面板的纵向加劲肋，承担14.30%～20.52%，最后其分配比例稳定在约17%。中纵梁的比例最大达到39.13%，在12%左右不再有大幅的变化。上弦杆的分配比例先增大后减小再增大是波浪变化的，分配比例在10.52%～32.5%之间。索力的水平分力向前传递，逐渐减小。拉索水的平分力的分配比例，桥面板的分配比例与上弦杆相当，上弦杆在当前节段比例最大45.6%～58.61%，下个节段时比例为33.4%～40.6%，是受力比例最大的构件。中纵梁所占的比例随距离的增大而减小，最后基本稳定在16%左右，桥面板加劲肋最后趋于约15%。构件的水平力分配上弦杆承担最多，然后是桥面板，中纵梁承担比例大于纵向加劲肋。
[Abstract]:The slab-truss composite structure is a structure which is subjected to the joint force of deck slab and truss. Because the structure has better comprehensive and efficient performance, it becomes the choice of most bridges. The deck slab considers the orthotropic steel bridge slab with high strength, light weight and low building height. Because of its continuous structure and convenient installation, the slab-truss composite structure has become the best choice for large and medium span bridges in the world. In this paper, the experimental study of the Dongshuimen Yangtze River Bridge under construction in Chongqing is carried out, with emphasis on the analysis of the bridge deck plate, stiffened rib, middle longitudinal beam, chord and cross beam in the upper structure under the action of stay cables. According to the constitutive relation of the material, the stress distribution of each member in the structural model under different load conditions is analyzed in detail by using Midas FEA, and the distribution ratio of the forward bridge force produced by the cable to each member is analyzed in detail. The bearing capacity of each component to the horizontal force of the cable. At the same time, the actual bridge test is carried out in the construction stage of the bridge. The sensors are arranged to the members of the construction site, the data are collected and the results of finite element calculation and the test results of the real bridge are compared and analyzed. Verify the reliability and accuracy of finite element analysis. The results show that under the action of cable, the components of the upper deck are uniformly distributed and the stress value increases with the increase of the distance from the cable to the cable. The position behind the cable hole, the deck of the bridge is all tensioned and diffused backward. The diffusion angle is 47 degrees with X, up to the upper chord, the stress is pressed in front of the cable along the bridge and pulled after the cable. The stress condition of the other upper members is similar to that of the bridge deck plate under .9# cable force. The main reason is that the vertical force of the stay cable produces additional bending moment to the structure. Finally, it is obtained that the distribution ratio of bridge deck slab tends to stabilize in the range of 28.2121 / 60.722.In order to bear the largest horizontal force, the proportion of the bridge deck slab decreases first, then increases, then decreases, and then tends to stabilize, accounting for about 40%. The longitudinal stiffening rib of the deck plate bears 14.30 points and 20.52 points, and its distribution ratio is stable at about 17.7%. The maximum ratio of midcolumn is 39.13%, and there is no significant change in about 12%. The distribution ratio of the upper chord increases first and then decreases and then increases, and the distribution ratio is between 10.52% and 32.5%. The horizontal component of the cable force passes forward and gradually decreases. The distribution ratio of the equal force between the cable and the bridge deck is equivalent to that of the upper chord. The maximum proportion of the upper chord in the current segment is 45.6and 58.61, and the proportion of the next section is 33.44.40.6. it is the component with the largest force ratio. The proportion of the middle longitudinal beam decreases with the increase of the distance, and the final stability is about 16%, and the stiffening rib of the bridge deck finally tends to be about 15%. The upper chords bear the most horizontal force, then the bridge deck, and the ratio of the longitudinal beam to the longitudinal stiffener is greater than that of the longitudinal stiffener.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U441.5

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