锈蚀钢筋混凝土梁的斜截面抗剪承载能力

Shear Carrying Capacity of Corroded Reinforced Concrete Beams

考虑钢筋锈蚀对受力钢筋截面面积和力学性能、钢筋与混凝土间粘结强度以及混凝土保护层厚度的影响,基于“拉、剪临界破坏”的概念和“梁-拱”共同作用的混凝土抗剪抵抗机制,建立了锈蚀无腹筋(主要指箍筋)梁的抗剪承载力公式;考虑梁中纵筋和(或)箍筋锈蚀的影响,基于箍筋与混凝土抗剪作用相互影响的机制,采用相应于有腹筋梁的无腹筋梁对抗剪强度的贡献与箍筋对抗剪强度的贡献相加的模式,建立了锈蚀有腹筋梁的抗剪强度公式.并且,对所建立的锈蚀钢筋混凝土梁的抗剪承载力的理论预测进行了试验验证.

Considering the influence of corrosion of reinforcing bar on the cross-section and mechanical properties of the reinforcing bar, the bond strength between steel and concrete as well as the reduction of the effective depth of the compressive concrete, shear carrying capacity of corroded reinforced concrete （RC） beams without web reinforcement （here the web reinforcement is mainly stirrup） was proposed on the basis of the concept of the critical tensile-shear failure stress state of plain concrete and the combined shear resistance of beam action and arch action. Then, considering the influence of corrosion of longitudinal steel and （or） stirrups, the superposition of the concrete shear resisting mechanism of the corresponding RC beam without web reinforcement and stirrup capacity was adopted on the basis of the interaction of concrete shear resisting mechanism and stirrup action; and the shear strength of corroded RC beams with web reinforcement was proposed. Finally, the proposed shear carrying capacities of corroded RC beams were compared with the corresponding test results.