CFRP加固钢筋混凝土梁受剪承载能力实用计算方法

在综合国内外粘贴碳纤维布加固钢筋混凝土梁受剪承载能力计算理论的基础上,重点分析了基于Khalifa(2000)有效应变修正模型及Schnerch(2001)有效应变模型的抗剪加固计算理论,通过比较粘贴碳纤维布抗剪加固梁试验值与理论值的吻合程度,指出了Khalifa(2000)有效应变修正模型的不足。最后,根据我国《混凝土结构设计规范》(GBJ50010-2002)和《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTJ023-85)及(JJGD62-2004),建立了基于Schnerch有效应变模型的抗剪加固梁受剪承载力计算方法,通过与试验值对比,所提抗剪加固公式的计算结果是安全可靠的,可用于实际结构的抗剪加固设计。

SHEAR DESIGN METHODOLOGY FOR RC BEAMS STRENGTHENED IN SHEAR WITH CFRP

This paper is concerned with the development of a simple design model for the calculation of the fiber reinforced polymer contribution to the shear capacity of FRP-strengthened RC beams.Existing design proposals for computing the shear capacity of RC beams strengthened in shear with CFRP are briefly reviewed,and their deficiencies highlighted.A new simple shear design model is then developed based on the modified effective average CFRP stress model presented by Khalifa(2000)and the effective strain model presented by Schnerch(2001).Two models are validated against experimental data.The results indicate that Khalifa(2000)effective strain model fails to calculate the shear capacity of strengthened beams with more than two CFRP plies.Finally,according to the specifications for concrete structures(GBJ50010-2002)and the specifications for highway bridges and culverts(JTJ023-85)and(JTG D62-2004),a simple design approach for computing the shear capacity is presented.Test results are used to validate the present shear design approach,and the results show that the proposed design approach is conservative and acceptable.