大跨径钢桥高粘沥青桥面铺装力学分析

发布时间：2018-07-10 07:47

  本文选题：高粘沥青 + 钢桥　； 参考：《山东建筑大学》2017年硕士论文

【摘要】：改革开放以来,我国经济社会发展取得了举世瞩目的成就,与经济社会发展密切相关的交通运输业有了重大的发展,桥梁建设也实现了跨越式的发展。20世纪90年代至今,我国建设了许多大跨径桥梁,其中大型钢桥结构具有结构较轻、经济性较好的特点,从而使得大跨径钢桥得到了广泛的应用。相关数据表明,截止到2016年我国已建成的跨度大于300米的钢桥已超过50座。与此同时,交通量和重型车数量的迅速增加以及日益加重的超载现象使桥面铺装层的破坏情况变得越发严重,某些大跨径桥梁在通车后不久,桥面铺装就不同程度的出现了开裂、拥包、车辙、推移、脱层、脱空、坑槽等病害。特别是一些交通量较大的大跨径桥梁的桥面铺装,其维护相对困难,而且一旦破坏,就必须进行维修,进而导致交通拥堵,从而会对我国经济社会发展造成巨大的损失。由此可见,桥面铺装成为制约大型钢桥建设和发展的一个关键因素。为了解决该问题,各国专家学者做了大量的研究工作,他们认为采用高粘沥青作为铺装层材料可有效的改善铺装层和钢板交界面的受力状况,减少铺装层剪切破坏。同时,由车辆荷载和温度差所引起的铺装层开裂等病害也能得到有效的降低和改善。但是高粘沥青混合料是一种新型桥面铺装材料,其在我国起步时间较晚,力学特性尚不明确,高粘沥青铺装层的设计急需完善的理论研究做指导。鉴于此,本文开展了高粘沥青作为大跨径钢桥桥面铺装材料的力学特性研究。本文利用有限元软件ANSYS对高粘沥青不同厚度的铺装层进行静力学、动力学分析。在静力学分析中采用了不同的加载位置,以静态模量作为所需的弹性模量,在动力学分析中采用动态模量作为所需的弹性模量,以此来明确最佳铺装层厚度和形式,并且选取SBS沥青、环氧沥青来作为对比,分析其力学特性的差异,从而分析得出三种材料的优劣性;在选定铺装层厚度和形式的前提下,分别选取60℃(高温)、20℃(中温)、-10℃(低温)三个温度条件,以此来分析高粘沥青混合料作为铺装层材料随温度变化而发生的力学特性变化,从而明确温度的效应;最后,本文对桥头有无剪力键时的力学响应进行了分析,以明确桥头剪力键的作用。本文通过研究获得以下结论;(1)大跨径钢桥高粘沥青铺装层的最佳铺装形式与厚度为单层5cm,荷载最不利位置为荷载2;(2)同为大跨径钢桥铺装层材料,高粘沥青混合料要优于SBS沥青混合料,与环氧沥青混合料相比则各有优劣,高粘沥青混合料受抗特性好于环氧沥青混合料,抗剪性不如环氧沥青混合料;(3)铺装层温度从60℃(高温)变化到20℃(中温),再到-10℃(低温),高粘沥青铺装层力学特性随之发生了较大的变化;(4)桥头设置剪力键对桥头位置高粘沥青铺装层底层的水平剪应力(剪力键后方)具有有效的降低作用。
[Abstract]:Since the reform and opening up, China's economic and social development has made remarkable achievements, and the transportation industry, which is closely related to the economic and social development, has made great progress. The bridge construction has also achieved a leapfrog development from the 1990s to the present. Many long-span bridges have been built in China, among which the large steel bridges have the characteristics of lighter structure and better economy, which makes the long-span steel bridges widely used. By 2016, more than 50 steel bridges with a span of more than 300 meters had been built in China. At the same time, the rapid increase in traffic volume and the number of heavy vehicles, as well as the increasing phenomenon of overloading, have made the destruction of deck paving more serious, and some long-span bridges have not long been opened to traffic. Bridge deck pavement on varying degrees of cracking, pack, rut, bed, delamination, void, potholes and other diseases. In particular, the pavement of some long-span bridges with large traffic volume is relatively difficult to maintain, and once damaged, it must be repaired, which will lead to traffic congestion, which will cause huge losses to the economic and social development of our country. Thus, deck pavement becomes a key factor restricting the construction and development of large steel bridges. In order to solve this problem, experts and scholars all over the world have done a lot of research work. They think that using high viscosity asphalt as pavement material can effectively improve the stress condition of the interface between pavement and steel plate, and reduce the shear failure of pavement. At the same time, pavement cracking caused by vehicle load and temperature difference can also be effectively reduced and improved. However, high viscosity asphalt mixture is a new bridge deck pavement material, which started late in our country, and its mechanical properties are not clear yet. The design of high viscosity asphalt pavement needs to be guided by perfect theoretical research. In view of this, the mechanical properties of high-viscosity asphalt as bridge deck pavement material of long span steel bridge are studied in this paper. In this paper, the finite element software ANSYS is used to analyze the statics and dynamics of high viscosity asphalt pavement with different thickness. In the static analysis, different loading positions are adopted, the static modulus is taken as the required elastic modulus, and the dynamic modulus is used as the required elastic modulus in the dynamic analysis, so as to determine the best thickness and form of the pavement. And choose SBS asphalt and epoxy asphalt as contrast, analyze the difference of their mechanical properties, and then analyze the advantages and disadvantages of three kinds of materials; under the premise of selecting the thickness and form of pavement, Three temperature conditions, 60 鈩，

本文编号：2112688