【作者】 薛辉；

【导师】 程东辉；

【作者基本信息】 东北林业大学 ， 桥梁与隧道工程， 2009， 硕士

【摘要】 CFRP筋具有轻质、高强、耐腐蚀等特点,作为增强材料替代钢筋在混凝土结构中应用,可有效避免因钢筋锈蚀引起的混凝土结构承载力的下降和耐久性的降低,减少工程维护费用。本文以CFRP筋作无粘结预应力筋、同时配置一定数量的非预应力钢筋,设计制作了4根无粘结CFRP筋部分预应力混凝土简支梁,通过静载试验考察该类构件的受弯性能。在对试验数据进行分析的基础上,提出了无粘结CFRP筋部分预应力混凝土简支梁中无粘结CFRP筋在使用阶段和正截面承载能力极限状态时的应力增量计算公式;根据实测荷载-挠度曲线并结合基于双折直线理论的刚度计算模式,提出了这类构件在荷载效应标准组合作用下短期刚度计算公式;同时探索了这类梁裂缝分布规律和平均裂缝间距计算方法。采用通用有限元软件ANSYS对无粘结CFRP筋部分预应力混凝土梁在外荷载作用下的受力性能进行了非线性有限元分析,对建模方法、单元选取、材料本构关系的定义、求解方法等进行了说明。主要分析的内容有梁的极限承载力、梁的挠度、梁的正应力与应变、CFRP筋的应力变化。并将计算结果与试验结果进行对比,吻合情况良好,从而验证了试验结果的正确性。更多还原

【Abstract】 Carbon Fiber reinforcement polymer tendon(FRP tendon) has many advantages such as corrosive resistance,high strength and lightweight.It can replace steel bar in concrete structure, which can avoid deterioration of bearing capacity and durability due to corrosion of steel bar and reduce the maintenance cost.4 unbonded partially prestressed CFRP reinforced concrete simple beams are designed, which are reinforced with CFRP unbonded tendons and a certain number of non-prestressed reinforcements.The flexural performance of this kind of beam is investigated.On the basis of analysis on test data,the calculation formula of stress increment of CFRP tendon in the beam during serviceability and ultimate limit state.The calculation formula of short-term stiffness of the beam is presented under characteristic combination of load based on test curve of loaddeflection and the twi-line theory.At the same time,the law of distribution of crack and the calculation method of the average spacing of crack are explored.Nonlinear finite element analysis on the mechanical performance of unbonded partially prestressed CFRP reinforced concrete simple beam under load is made by using ANSYS Software.The modeling method,the unit,constitutive relation of material and solving methods are illustrated.The ultimate bearing capacity of beams,the deflection of beam,the normal stress and strain of beam and the stress variation of CFRP tendons are analyzed.The calculated results and the test results are compared and they are in good agreement,which verifies that the test result is correct.更多还原