【作者】 张铟；

【导师】 王乘； C.S.Cai；

【作者基本信息】 华中科技大学 ， 工程力学， 2006， 博士

【摘要】 纤维增强复合材料(Fiber Reinforced Polymer,简称FRP)是近年来在桥梁工程中开始应用的新型结构材料,它具有轻质、高强、耐腐蚀等显著特点。FRP夹心桥面板是最具应用前景的结构型式之一,它既可应用于老桥中损毁桥面板的更换修复,也可作为新建桥梁的桥面体系。由于FRP夹心桥面板是一种新型结构构件,对它在桥梁结构中的静、动力特性等还有很多急需了解的问题。荷载在桥面上的横向分布及荷载作用下桥梁的动力响应是桥梁设计中需要考虑的重要内容,世界各国在进行桥梁设计时普遍采用荷载横向分布系数和动力系数来考虑其影响因素。研究人员针对传统桥面板的荷载横向分布系数及动力系数的取值进行了深入广泛的研究(包括试验研究和理论研究)。FRP桥面板的一些性能(例如质量、刚度和阻尼性能等)和传统的混凝土或钢桥面板有很大的不同,这可能导致采用FRP桥面板桥梁的性能和采用传统桥面板桥梁性能的差异。但是研究人员对采用FRP桥面板的桥梁的特性还少有研究。因此,本论文采用数值分析方法对FRP桥面板桥梁的荷载横向分布情况及桥梁的动力响应进行了比较详细的研究。由于FRP夹心板复杂的几何构型,给采用有限元技术对FRP桥面板桥梁的整体模拟带来了困难,本文将FRP正弦夹心桥面板等效为正交各向异性实心板,分析结果与试验数据吻合良好,证明是一种对采用FRP夹心板的桥梁结构进行整体有限元分析的有效方法;利用等效模型,本文首先对堪萨斯州钢梁桥更换为FRP桥面板后的桥梁进行了整桥分析,其荷载横向分布情况与现场实验吻合良好,作者进一步研究了具有一般性的FRP桥面板钢梁桥和FRP桥面板预应力混凝土梁桥的荷载横向分布系数;考虑车-桥耦合系统,作者利用自编的MATLAB计算程序研究了FRP桥面板体系的动力性能,分别考察了FRP桥面板简支板桥、FRP桥面板钢梁桥和FRP桥面板预应力混凝土梁桥在三轴卡车荷载作用下的动力响应,得到了其在路面粗糙度、行车速度等影响下的动力特性;在对梁式桥所进行的静力及动力分析中作者均考虑了FRP桥面板与支承梁部分组合与完全组合两种构造情况,并与其它条件相同但采用混凝土桥面板的桥梁进行了对比分析,得到了一些有价值的研究结论。本文的研究为FRP桥面板在桥梁工程中更好的得到应用提供了理论基础。更多还原

【Abstract】 Fiber reinforced polymer (FRP) is a new structural material which is gaining popularity in the bridge community in recent years. It has shown superior properties such as high strength-to-weight ratio and corrosion resistance, etc. The FRP sandwich hollow panel is one of the FRP systems and has been proposed for applications in bridge construction with a good prospect. It can be applied for old bridge repair and replacement of damaged decks, and it can also be used in new bridge deck systems. Because the FRP bridge deck is a new structural component, there is a growing need to understand the behavior of FRP deck bridges such as the static and the dynamic response of bridges with a FRP deck.The load distribution throughout the bridge deck and the vehicle-induced impact on bridges are of primary importance in the design of bridges. The loads distribution factor and the dynamic impact factor have been used world wide in bridge design, and extensive research (including experimental and theoretical) has been conducted to determine these factors for bridges with conventional decks. The characteristics of the FRP decks (such as mass, stiffness and damping) are significantly different from those of the traditional concrete and steel decks, which could result in different performance of FRP deck bridges from the traditional bridges. However, the distinctive performance of bridges with FRP decks has rarely been studied. For this reason, some detailed numerical analyses are used in the present study to investigate the load distribution and the dynamic response of FRP deck bridges.Due to the geometrical complexity of the FRP sandwich panel configuration, finite element modeling and analysis for an entire bridge can be very complicated, if not impossible. The present study reduces FRP sinusoidal core sandwich panel to a solid orthotropic plate using the equivalent properties derived, the results obtained from the analysis with the simplified model were compared with those from the tests and a good correlation was achieved, so it was verified to be an effective method in investigating the performance of entire bridges with FRP deck; Using the equivalent model, at first the present study analyzed a steel girder bridge after the original deck was replaced with a FRP deck in Kansas. The load distributions obtained from the analysis were compared with those from the field tests and a good correlation was achieved. And then, some detailed finite element analyses were used to further investigate the load distribution of FRP bridge deck systems, a steel multi-girder bridge and a concrete multi-girder bridge were studied. By integrating the bridge and vehicle systems into a bridge-vehicle coupled system based on deformation compatibility, the present study using the developed MATLAB software this paper studied the dynamic performance of bridges with FRP decks, and investigated the dynamic response of a simple support slab FRP bridge, a steel multi-girder bridge with FRP deck, and a prestressed concrete multi-girder bridge with FRP deck. The dynamic response of bridges caused by a 3-axle truck was obtained considering the influence of road roughness as well as vehicle velocity. For both the static analyses and the dynamic analyses of FRP girder bridges, the author considered two composite actions which were FRP deck partially composite or FRP deck fully composite between the deck and girders. The performance of bridges was compared between the FRP and the corresponding concrete deck bridges, and some valuable research conclusions were obtained. This study provides some helpful rationale for the better application of FRP deck in the bridge community.更多还原