超高性能轻型组合桥面铺装体系基本力学性能研究

发布时间：2018-04-05 08:09

本文选题：钢桥面铺装　切入点：超高韧性混凝土　出处：《湖南大学》2014年硕士论文

【摘要】：钢桥面铺装层作为大跨径桥梁的重要组成部分,越来越受到学者和工程师的关注。然而,目前的钢桥面铺装层却存在许多弊端,很容易出现早期病害,如车辙、铺装层开裂、脱层等。为解决钢桥面铺装层易损坏的问题,本文提出将薄层聚合物混凝土TPO铺筑于超高韧性混凝土STC和钢桥面板之上,形成超高性能的轻型组合桥面铺装体系,简称STC+TPO。本文主要开展STC+TPO铺装体系基本力学性能研究,取得了如下研究成果：概括了钢桥面铺装体系的受力特点和常见病害,总结出钢桥面铺装易损坏的两个根本原因：桥面系刚度不足和铺装材料在物理力学性能方面存在缺陷。针对目前钢桥面铺装的不足,提出STC+TPO铺装,并将其设计控制指标确定为铺装层拉应力指标和层间剪应力指标通过对STC、TPO材料性能及界面强度的研究,得到了两种材料的力学参数和界面的粘结性能参数。研究表明STC、TPO材料具有优良的性能,足以胜任钢桥面铺装；STC-钢板、STC-TPO的界面粘结性能优异,能够保证层间的可靠粘结。以上材料基本参数的获取,也为后面的力学分析和强度可靠性分析提供了依据。本文基于验证过的北江马房大桥有限元模型,分析了STC+TPO铺装体系的受力和变形特点。计算结果表明,采用STC+TPO铺装体系,能有效降低钢桥面板和铺装层的应力应变幅值和局部竖向变形。此外,车辆荷载、环境温度和铺装层厚度等对STC+TPO铺装体系的受力状况有较大影响。通过综合考虑多参数的影响,得到STC+TPO的最不利受力状态,并计算了此状态下铺装层中的应力值。本文对STC+TPO铺装体系的动力特性进行了初步分析,并将动力解与静力解进行了对比。计算结果表明：铺装层最大竖向位移的动力解与静力解基本相同；铺装层最大拉应力的动力解与静力解则相差较大,其冲击系数受车辆参数和铺装层结构参数的共同影响,但冲击系数的值均小于0.2,这也说明静力分析中取0.3的冲击系数是安全可靠的。结合动力、静力分析的结果和材料性能参数,本文对STC+TPO铺装体系的强度可靠性进行了分析。结果表明：STC和TPO的抗拉强度及界面抗剪强度均满足重载和高温环境下的使用要求。从以上结果可知：STC+TPO是一种性能优异的铺装,能够解决钢桥面铺装层易损坏的难题。
[Abstract]:As an important part of long-span bridge, steel deck pavement is paid more and more attention by scholars and engineers.However, the present steel bridge deck pavement has many disadvantages, such as rutting, pavement cracking, delamination and so on.In order to solve the problem that steel bridge deck pavement is easy to be damaged, this paper puts forward that the thin-layer polymer concrete (TPO) is constructed on the top of ultra-high toughness concrete (STC) and steel bridge face slab to form ultra-high performance lightweight composite deck pavement system (STC TPO).In this paper, the basic mechanical properties of STC TPO pavement system are studied, and the results are as follows:This paper summarizes the mechanical characteristics and common diseases of steel bridge deck pavement system, and summarizes two fundamental reasons for the easy damage of steel bridge deck pavement: insufficient stiffness of deck system and defects in physical and mechanical properties of pavement materials.In view of the deficiency of steel bridge deck pavement at present, STC TPO pavement is put forward, and its design control index is determined as tensile stress index and interlayer shear stress index.By studying the properties and interfacial strength of STC TPO materials, the mechanical parameters and bond properties of the two materials were obtained.The results show that the STC- TPO material has excellent properties, which is sufficient for the interfacial bonding of STC-TPO in steel bridge deck pavement, and can guarantee the reliable bond between the layers.The acquisition of the basic parameters of the above materials also provides the basis for the mechanical analysis and strength reliability analysis.Based on the verified finite element model of Bei Jiang Mafang Bridge, this paper analyzes the stress and deformation characteristics of STC TPO pavement system.The calculation results show that the stress and strain amplitude and local vertical deformation of steel bridge slab and pavement can be effectively reduced by using STC TPO paving system.In addition, vehicle load, ambient temperature and pavement thickness have great influence on the stress of STC TPO pavement system.By considering the influence of multiple parameters, the most unfavorable stress state of STC TPO is obtained, and the stress values in the pavement under this condition are calculated.In this paper, the dynamic characteristics of STC TPO pavement system are preliminarily analyzed, and the dynamic and static solutions are compared.The results show that the dynamic solution of the maximum vertical displacement of the pavement is basically the same as the static solution, and the dynamic and static solutions of the maximum tensile stress of the pavement are quite different, and its impact coefficient is affected by the vehicle parameters and the structural parameters of the pavement.However, the impact coefficient is less than 0.2, which also shows that the impact coefficient of 0.3 is safe and reliable in static analysis.Combined with the results of dynamic, static analysis and material performance parameters, the strength reliability of STC TPO pavement system is analyzed in this paper.The results show that the tensile strength and the interfacial shear strength of TPO and w STC meet the requirements of heavy load and high temperature environment.From the above results, it can be seen that TPO is a kind of pavement with excellent performance, which can solve the problem that steel bridge deck pavement is easy to be damaged.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U443.33

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