装配式空心板桥破坏机理与加固技术研究

发布时间：2018-03-22 15:17

本文选题：装配式空心板桥　切入点：铰缝　出处：《北京交通大学》2015年硕士论文　论文类型：学位论文

【摘要】：装配式空心板桥是我国中小跨径桥梁的主要结构形式,以山西省为例空心板桥约占该省全部中小跨径梁桥的81.8%。随着时间的推移,大量装配式空心板桥显现出许多相似的病害,以铰缝损坏开裂、板桥横向整体性降低最为突出,有的甚至影响到桥梁的安全运营。为此,有必要在充分了解装配式空心板桥的使用现状基础上,对常见主要病害进行针对性研究。本文首先对山西省现役的2510座装配式空心板桥的调查数据进行分析,掌握了空心板桥的设计荷载等级、桥梁跨径、结构类型之间的内在联系及空心板桥的典型病害、现有加固方法,发现铰缝病害是影响该类型桥梁安全性的主要因素之一。其次,借助Abaqus有限元软件建立常见10m跨装配式简支空心板梁桥线弹性模型,分析铰缝内部及铰缝与板梁接触面的应力随荷载横向、纵向移动时的变化规律;而后建立10m跨装配式简支空心板梁桥铰缝结构的非线性模型,在结构最不利加载位置(桥梁1/2跨和1/8跨处)进行加载直至结构破坏,并分别分析有桥面铺装和无桥面铺装时铰缝应力随荷载变化的发展规律。接着,以《公路桥涵标准图》中10m跨钢筋混凝土桥和13m、16m跨预应力混凝土桥为对象进行桥面铺装改造、板底张拉横向预应力、板底粘锚钢横梁和铰缝压力注胶4种提高空心板桥横向整体性加固方法的对比分析,并借助Midas有限元软件对各加固方法的可行性进行验算。弹性分析表明：纵向剪应力τ1的控制位置在1/8跨度附近的铰缝内部：铰缝内部和接触面的竖向剪应力τ2数值相近,最不利加载位置在跨中近铰缝处；法向应力σn的最不利加载位置与τ：相同。非线性分析表明：铰缝下部侧面为结构最薄弱位置,最易出现法向粘结失效；铰缝内上部位置容易出现纵向剪切破坏现象；铰缝中部侧面是铰缝结构的主要传力部位,结构荷载的传递主要由铰缝中部侧面的竖向剪切强度、法向粘结强度及桥面铺装共同承担。4种加固方法的对比发现：桥面铺装改造是常见的有效改善结构横向整体性的方法,但不同跨径桥梁的合理铺装层厚度不同。静载试验表明,桥面铺装改造可以有效提高装配式空心板桥横向整体性。
[Abstract]:The fabricated hollow slab bridge is the main structural form of the middle and small span bridges in China. Taking Shanxi Province as an example, the hollow slab bridge accounts for about 81.8% of all the small and medium-sized span beam bridges in the province. With the passage of time, a large number of fabricated hollow slab bridges show many similar diseases. The cracking of hinged joints makes the transverse integrity of the slab bridge most prominent, and some even affect the safe operation of the bridge. Therefore, it is necessary to fully understand the present situation of the use of the fabricated hollow slab bridge. The main diseases were studied. In this paper, the investigation data of 2510 prefabricated hollow slab bridges in Shanxi Province are analyzed, and the design load grade, bridge span, structural type and typical diseases of hollow slab bridges are grasped. Existing reinforcement methods have found that hinge joint disease is one of the main factors affecting the safety of this type of bridge. Secondly, the linear elastic model of 10m span simple supported hollow slab girder bridge is established by Abaqus finite element software. The variation of stress in hinge joints and the interface between hinged joints and slab beams with transverse and longitudinal loads is analyzed, and then the nonlinear model of hinged joints of 10m span prefabricated hollow slab girder bridges is established. At the most unfavorable loading position of the structure (1 / 2 span and 1 / 8 span of the bridge), the structure is subjected to loading until the structure is destroyed, and the evolution of the stress of hinged joints with and without deck pavement is analyzed respectively. Taking the 10m span reinforced concrete bridge and the 13m span prestressed concrete bridge as the objects, the bridge deck is paved, and the slab is prestressing with the transverse tension at the bottom of the slab, the concrete bridge with 10 m span and the prestressed concrete bridge with 13 m span span is taken as the object. The comparison and analysis of four methods to improve the transverse integrity of hollow slab bridge are carried out by means of Midas finite element software, and the feasibility of each reinforcement method is verified by means of Midas finite element software. The elastic analysis shows that the control position of longitudinal shear stress 蟿 1 is near 1 / 8 span, the vertical shear stress 蟿 2 in the joint and the contact surface is similar, and the most unfavorable loading position is near the hinge joint. The most unfavorable loading position of normal stress 蟽 n is the same as 蟿: the nonlinear analysis shows that the bottom side of the hinge joint is the weakest position of the structure, and the normal bond failure is the most likely, and the longitudinal shear failure is easy to occur in the upper part of the hinge joint. The middle side of the hinge joint is the main force transfer part of the hinged joint structure, and the load transfer of the structure mainly depends on the vertical shear strength of the middle side of the hinge joint. The comparison of normal bond strength and bridge deck pavement reinforcement methods shows that the bridge deck pavement reconstruction is a common and effective method to improve the transverse integrity of the structure, but the reasonable pavement thickness of different span bridges is different. The static load test shows that the bridge deck pavement reconstruction is a common and effective method to improve the transverse integrity of the structure. The improvement of deck pavement can effectively improve the transversal integrity of the assembled hollow slab bridge.
【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U445.72

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