【作者】 潘云锋；

【导师】 韩小雷； 于国友；

【作者基本信息】 华南理工大学 ， 结构工程， 2011， 硕士

【摘要】 钢筋混凝土桥梁结构暴露在外环境中,易导致钢筋的锈蚀,影响结构的工作性能,严重时将会影响结构的承载性能。GFRP筋具有高耐腐蚀性、密度小和热膨胀系数同混凝土相近等优点,GFRP筋被认为能够代替钢筋在工程中应用。但目前应用并不广泛,主要原因是较高的建造价格使其无法在桥梁工程中推广,而现行FRP筋混凝土结构设计规范的配筋率远高于钢筋混凝土桥面板的配筋率。已有的研究表明,传统的梁板式桥梁结构中存在压缩薄膜效应。结合压缩薄膜效应对混凝土桥面板结构设计将有效的降低桥面板的配筋率,降低结构的建造成本。本文在以往的研究成果上,对在轮胎荷载下的GFRP筋梁板式桥梁面板的工作性能和承载力计算方法进行研究,主要进行如下几方面的工作:1.以支撑梁宽度、筋材种类、配筋率为参数,对1:3比例缩小的梁板式桥面板进行静力加载试验,测量各个结构模型在整个加载过程中各阶段的承载力、应变、变形等数据,考察其基本力学性能,并对承载力计算方法进行初步探讨。2.分析研究桥面板在轮胎荷载下,支撑梁侧向位移、桥面板的裂缝扩展和破坏形态,清晰揭示压缩薄膜效应在整个受力过程中的变化以及对结构性能的影响。3.采用有限元软件ABAQUS对桥面板静力加载时荷载-变形全曲线进行模拟,模拟结果与试验数据吻合,较为充分说明了本文有限元模拟的合理性。并进一步分析受力过程中桥面板沿截面高度应力分布规律,深入揭露了梁板式桥面板轮胎荷载下的工作机理。基于准确校正试验的基础上展开参数分析。4.通过对试验结果和数值模拟的归纳分析,本文对原有的基于压缩薄膜效应的钢筋混凝土桥梁面板承载能力的计算方法进行了修正。修正后的结果与试验结果有着较好的吻合。通过试验及有限元分析发现,由于压缩薄膜效应的存在,桥面板的极限承载力大幅提高,且低配筋桥面板与高配筋桥面板的承载性能差异不大。基于压缩薄膜效应的GFRP筋梁板式桥面板设计在保证承载性能的基础上将有效的降低结构的建造成本,为桥面板解决可持续性提供一种新思路。更多还原

【Abstract】 Due to the exposure in enviroments,deterioration of reinforced concrete bridge deck slabs caused by corrosion of reinforcement has become increasingly evident.Glass Fiber Polymer(GFRP) with strong corrosion-resistant,light weight and small thermal expansion coefficient is considered as a possible replacement of steel reinforcement in paractical engineering.However,due to the higher price of GFRP and larger reinforcement ratios,which is caused by the traditional design methods,this reinforcement materials could be used widely.In the previous research,it was found that compressive membrane action(CAM) exited in the traditional slab-and-beam bridge deck structures.With the consideration of CMA in the structural design of concrete bridge deck slabs,the construction costs could be decreased.Based on previous studies, a research on structural behaviours of GFRP reinforced concrete bridge deck slabs and the related prediction methods of loading capacities was carried out in this paper.The main achievement can be summarized as follows:1. A series of one-third scaled experimental tests of GFRP reinforced concrete bridge deck slabs under static patch loads was carried out.The influences from some structural variables were considered,which included width of supporting beams,reinforcing materials and reinforcement percentages.In this study,some structural parameters,such as applied load,stress&strain,cracking conditions,were measured in different stages.Furthermore,the prediction methods of loading capacities were discussed.2. The structural behaviours of GFRP reinforced concrete bridge deck slabs was discussed,including displacements of supporting beams,cracking patterns and failure mechanism.The influced from CMA on bridge deck slabs was revealed clearly.3. A commercial software named ABAQUS was used to numerical study the structural response,such as load vs. deflection,in GFRP reinforeced concrete bridge decks.A good colletion between finite element analysis and experimental tests was shown in the comparisons.According to the accuracy of established nonlinear finte analysis,a further research on structural behaviours of this structural type,such as stress distribution,was carried out,which was used to reveal the failure mechanism of GFRP reinforced concrete bridge deck slabs.Thereafter,a series of parametric study was conducted.4. Based on the analytical results of experimental tests and numerical analysis,a modified prediction methods was proposed.The predicted result showed a good agreement with experimental results.In the study of experimental tests and numerical modeling, the existing of CMA enhanced the loading capacities of GFRP reinforced concrete bridge deck slabs. The structural behaviours of GFRP reinforced concrete bridge deck slabs with lower reinforcement percentages are similar to those in slabs with higher reinforcement ratios. In this study, it was found that introduction of GFRP with consideration of CMA could be a effective solution of improvement of sustainability of bridge deck slabs.更多还原