【摘要】 为研究纤维增强复合材料(Fiber Reinforced Polymer, FRP)-超高性能混凝土(Ultra-High Performance Concrete, UHPC)组合梁的受剪性能，通过四点弯曲试验和精细化有限元分析对带FRP剪力键(FRP Shear Key, FSK)的FRP-UHPC组合梁进行研究.分别采用混凝土塑性损伤模型和Puck失效准则来模拟混凝土和FRP型材的损伤演化，并采用双线性内聚力模型来模拟组合界面的力学行为.有限元结果与试验结果进行对比表明二者吻合较好.基于已验证的模型开展参数化分析，重点研究混凝土板强度、高度和宽度，FRP腹板抗剪强度、剪切模量、高度和厚度，以及FSK间距等对带FSK的FRP-UHPC组合梁受剪性能的影响.研究结果表明，组合界面间布置FSK处的局部滑移远小于未布置FSK处的局部滑移，且最大局部滑移小于4mm,验证了FSK具有良好的界面抗剪作用；增大混凝土板强度和截面尺寸均能提高组合梁的抗剪刚度和承载力.与普通混凝土板相比，UHPC板可有效抑制界面滑移；提高FRP腹板的抗剪强度和厚度可提高组合梁的抗剪承载力和变形，且破坏模式由剪切破坏向弯曲破坏转变；减小FSK间距可有效提高界面间的抗剪性能，增强组合梁的组合效应，提高承载力和变形.更多还原

【Abstract】 To study the shear performance of Fiber-Reinforced Polymer(FRP)-Ultra High Performance Concrete(UHPC) composite beams, the FRP-UHPC composite beams with FRP shear keys(FSKs) were investigated through four-point bending tests and refined Finite Element(FE) analysis.The concrete damaged plasticity model and the Puck failure criterion were used to simulate the progressive damage of concrete and FRP profiles, respectively.The mechanical behavior of the interface was simulated using a bi-linear cohesive zone model.The comparison between the FE analysis and experimental results demonstrates a good agreement.Based on the validated model, a parametric analysis was conducted on the shear performance of FRP-UHPC composite beam with FSKs, focusing on the effect of parameters such as concrete slab strength, height and width, FRP web shear strength, shear modulus, height and thickness, and FSK spacing.The results indicate that the local slip of the composite interface with FSK is much smaller than that of without FSK,and the maximum local slip is less than 4mm, which verifies that FSK has good interfacial shear resistance.Increasing the strength and section size of the concrete slab can improve the shear stiffness and the shear capacity of the composite beam.Besides, the use of UHPC for concrete slabs can also effectively inhibit interface slip.Increasing the shear strength and thickness of FRP web can improve the shear strength and deformation, the failure mode changes from shear failure to bending failure.The reduction of FSK spacing can effectively enhance the shear performance of the interface, thereby improving the combined effect of the composite beam and increasing its bearing capacity and deformation.更多还原