系杆拱桥增加吊杆加固方法研究

发布时间：2018-01-27 01:42

本文关键词： 系杆拱桥刚性吊杆病害主动加固　出处：《长安大学》2014年硕士论文　论文类型：学位论文

【摘要】：系杆拱桥以其简洁优美的造型，低廉的建造成本，以及较低的地质条件要求等特点，在我国得到了广泛应用。随着经济的发展，公路交通量急剧加大，一部分系杆拱桥结构病害情况日益严重，对于采用刚性吊杆的系杆拱桥，由于当时的设计几乎都没有考虑吊杆的检测与更换，所以如何对此类桥型进行加固成为了一个重要课题。本文对在役的刚性吊杆系杆拱桥开展调研与分析，对系杆拱桥所存在的主要病害进行了整理分类并对病害成因进行了分析；通过有限元模型对吊杆在恒载和活载作用下的轴力、剪力和位移进行分析；在荷载作用下，系杆拱桥的拱肋与系梁将会发生位移与变形，使吊杆上下端与拱肋、系梁的连接处产生附加内力，在长期运营过程中附加内力的累积将会造成系杆拱桥的吊杆破坏；针对刚性吊杆系杆拱桥加固，建议了一种增设吊杆的主动加固方法，此方法通过在原吊杆间设置新吊杆，使其承担部分荷载，卸除部分原吊杆力，增加原吊杆的压应力储备，最终形成整体内力相互协调的共同受力状态；具有以简单的方式改善桥梁结构受力，施工简单，交通影响较小等特点，在后期运营过程中，，可根据需要及时调整更换吊杆。本文根据依托工程，采用Midas软件建立有限元模型，对比分析了加固前后结构主要受力构件的内力变化，并对施工监控结果进行了分析。加固结果表明，刚性吊杆受力状况得到明显改善，原混凝土吊杆压应力储备明显提高，消除了混凝土吊杆的裂缝病害，桥梁承载能力和耐久性得到了提高，达到了良好的加固效果。
[Abstract]:Tied arch bridge has been widely used in China because of its simple and beautiful shape, low construction cost and low geological requirements. With the development of economy, the traffic volume of highway increases rapidly. Some of the structural diseases of tied arch bridges are becoming more and more serious. For the tied arch bridges with rigid suspenders, the detection and replacement of suspenders are almost not considered in the design at that time. So how to strengthen this kind of bridge has become an important subject. This paper investigates and analyzes the rigid suspenders tied arch bridge in service, classifies the main diseases existing in the tied arch bridge and analyzes the causes of the disease. The axial force, shear force and displacement of the suspender under dead and live load are analyzed by finite element model. Under the load, the arch rib and the tie beam of the tied arch bridge will displace and deform, which will cause the additional internal force between the upper and lower end of the suspender and the arch rib and the connection of the tie beam. The accumulation of additional internal forces during the long term operation will result in the failure of the suspenders of the tied arch bridge. In view of the reinforcement of rigid suspenders tied arch bridge, a method of active reinforcement with additional suspenders is proposed. By setting new suspenders between the original suspenders, this method enables them to bear part of the load and remove part of the original suspender force. Increasing the compressive stress reserve of the original suspender, and finally forming the common stress state of the whole internal force coordinated with each other; With a simple way to improve the force of the bridge structure, simple construction, less traffic impact and other characteristics, in the later operation process, can be adjusted according to the needs of timely replacement of suspenders. The finite element model was established by using Midas software. The internal forces of the main structural members before and after reinforcement were compared and analyzed, and the results of construction monitoring were analyzed. The results show that the stress condition of rigid suspenders is obviously improved, the compressive stress reserve of the original concrete suspenders is obviously increased, the cracks of the concrete suspenders are eliminated, and the bearing capacity and durability of the bridges are improved. Good reinforcement effect has been achieved.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.225;U445.72

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