【作者】 王俊；

【导师】 周智；

【作者基本信息】 大连理工大学 ， 结构工程， 2015， 硕士

【摘要】 钢筋混凝土结构在服役期间受到环境因素(腐蚀、温度变化、降水等)、自然灾害(地震、冲刷、泥石流等)以及人为因素(车辆超载、恐怖袭击等)等多种因素的耦合影响,易出现诸如钢筋腐蚀、混凝土开裂等多种病害,直接导致结构承载能力下降,降低结构的服役性能和使用寿命,严重时甚至导致结构坍塌等灾害性事故,造成巨大的财产损失和人员伤亡。因此,对有损钢筋混凝土结构进行加固研究,提高其承载能力和延长其使用寿命具有重要意义。碳纤维板具有高强、轻质、耐腐蚀等优点,是进行结构加固的理想材料。预应力碳板加固作为一种高效加固方法,能够充分利用碳板的上述优点,可以有效地提高钢筋混凝土结构的承载力、刚度和抗裂性能。本文基于课题组研制开发的预应力碳板和改良的预应力加固锚头,通过理论分析、有限元模拟和试验验证方法开展大尺度有损钢筋混凝土梁预应力碳板加固研究,提高预应力碳板应用于预应力结构中的工程化产业化水平,主要内容包括：首先,对本文拟采用的碳纤维板和预应力挤压式锚具的性能进行系统试验研究,确定碳板的力学性能和锚具的锚固性能,以及对预应力碳板加固系统构架进行了介绍,为后续的预应力碳板加固试验提供条件；其次,对预应力碳板加固混凝土梁的受力过程、承载力计算方法进行了分析,以及对预应力碳板加固混凝土梁进行了有限元分析,研究了预应力碳板加固对承载力、抗弯刚度、裂缝开展的影响；同时对预应力碳板加固混凝土梁的主要影响因素进行了分析；最后,开展大尺度有损钢筋混凝土梁的预应力碳板加固试验研究,设计了三组不同工况的混凝土梁,分别研究预应力碳板加固对标准梁、少筋梁和裂缝梁的承载力、挠度、裂缝开展和梁的失效模式的影响,综合分析预应力碳板加固对大尺度有损钢筋混凝土梁的加固效果。同时,将有限元分析和理论计算结果与预应力加固试验结果进行了对比分析。更多还原

【Abstract】 Reinforced concrete structures in service are affected by environmental factors (corrosion, temperature variations, precipitation, etc.), natural disasters (earthquakes, erosion, landslides, etc.) and human factors (vehicle overloading, terrorist attacks, etc.). They are prone to a variety of diseases, such as steel corrosion, cracks of concrete. The diseases will influence service performance and service life of structures. Moreover, the diseases will lead to collapse of the structures. Research on the reinforcement of RC structures is of great significance.CFRP plate is an ideal material for structural reinforcement for its high strength, light weight, corrosion resistance and other excellent properties. As an effective reinforcement method, prestressed CFRP plates reinforcement can effectively improve the bearing capacity, the stiffness and crack resistance of reinforced concrete structures. In this dissertation, the prestressed CFRP plates strengthing method on large scale damaged reinforced concrete beams was studied.The content of this work mainly contains:Firstly, performance tests of the wedge-type anchors and CFRP plates were conducted to get advanced understanding of mechanism of prestressed CFRP strengthening system. By these tests, the anchoring coefficient of anchors and mechanical parameters of CFRP plates were determined.Secondly, the stress procedure and calculation method of ultimate bearing capacity are analyzed. Simulate the RC beams strengthed with prestressed CFRP plates with ANSYS. Calculate bearing capacity and flexural stiffness, the influence of crack propagation, and the influential factors of the reinforcement.Finally, design the experiment of three groups of concrete beam, respectively, standard beams, less reinforcement beams and crack beams. By experimental studies, bearing capacity, deflection, crack and failure mode of the beams were studied. At the same time, compare the results of the experiments with FEM analysis and design results.更多还原