FRP-Reinforced Concrete Columns under Cyclic-Reversed Loads

钢筋锈蚀问题是限制钢筋混凝土结构使用寿命的最大因素。在某些情况下，维修成本可能是初始成本的两倍。解决钢筋锈蚀问题的一个公认的解决方案是在钢筋混凝土结构中使用不可腐蚀的纤维增强聚合物(FRP)筋。在过去的二十年里，随着制造工艺的进步和大量成功的现场应用，广泛的研究努力导致了玻璃钢设计标准的发展。然而，由于缺乏这方面的研究资料，这些标准缺少地震区结构构件的设计程序和指南，这限制了FRP技术的广泛推广。这些结构构件的一个主要示例是RC柱。大量文献表明，柱的抗震能力不足是许多钢筋混凝土结构和桥梁在大地震中倒塌的最大可能原因，造成巨大的生命和财产损失。除了加拿大国家建筑规范要求对建筑物进行抗震分析外，在地震区使用线弹性FRP材料可能是有利的，因为FRP-RC结构在大漂移后会发生小的残余变形，从而减少了修复的需要。申请人的研究计划集中于通过为不同荷载和环境条件下的FRP-RC结构制定完整和包容的设计条款来更好地了解FRP加固在不同结构应用中的行为和使用。建议的研究将通过对FRP-RC柱在地震模拟荷载下的结构性能进行试验和分析研究来提供这些急需的数据并介绍设计程序。试验工作将在足尺尺寸的柱子上进行，这些柱子是基础上方柱子中最关键的部分。分析部分将包括FRP-RC柱的混凝土约束和粘结滑移模型的开发，这些模型将被进一步纳入非线性有限元软件，以进行广泛的参数研究。此外，这项拟议的研究计划将有助于对8名研究生(4名博士)进行独特的、高度专业化的培训，以降低交通部、市政当局和公共工程部等基础设施所有者的维护成本。

The corrosion problem of steel reinforcing bars is the greatest factor in limiting the life expectancy of reinforced concrete (RC) structures. In some cases, the repair cost can be twice as high as the initial cost. A well-recognized solution to overcome problems related to steel corrosion is the use of the non-corrodible Fibre-Reinforced Polymer (FRP) bars in RC structures. In the last two decades, extensive research efforts along with the advancement in manufacturing processes and numerous successful field applications have led to the development of FRP design standards. However, these standards are missing design procedures and guidelines for structural members in seismic zones due to a lack of research data in this area, which limits the wide spread of FRP technology. A prime example of these structural elements is RC columns. It is well-documented that the inadequate seismic resistance of columns is the most likely cause for the collapse of many RC structures and bridges in major earthquakes, leading to great loss of life and assets. In addition to the necessity of performing seismic analysis of buildings, as required by the Canadian national building code, the use of linear-elastic FRP materials in seismic regions could be advantageous due to the small residual deformations that occur in FRP-RC structures following large drifts, which result in reduced need for rehabilitation. The applicant's research program focusses on better understanding the behaviour and use of FRP reinforcement in different structural applications by developing complete and inclusive design provisions for FRP-RC structures under different loading and environmental conditions. The proposed research will provide this much needed data and introduce design procedures through conducting experimental and analytical investigations on the structural performance of FRP-RC columns under seismic-simulated loads. The experimental work will be conducted on full-scale columns representing the most critical part of a column above foundation. The analytical part will include the development of concrete confinement and bond-slip models for FRP-RC columns that will be further incorporated into a nonlinear finite element software to run an extensive parametric study. In addition, this proposed research program will contribute to the unique and highly specialized training of eight graduate students (4 PhD cutting the maintenance cost for infrastructure owners such as the Ministries of Transportation, Municipalities and Public Works.