ANALYSIS OF SHEAR RELIABILITY OF REINFORCED CONCRETE BEAMS STRENGTHENED WITH SNSM CFRP UNDER THE ACTION OF ENVIRONMENTAL EFFECTS
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摘要: 为了评估环境作用对侧面内嵌碳纤维增强复材(CFRP)加固钢筋混凝土梁抗剪可靠度的影响,在考虑环境作用的情况下建立了加固梁极限状态抗剪承载力功能函数时变模型;基于当量正态化法(JC法)计算不同恒载标准值与活载标准值比值下混凝土梁加固前后的时变抗剪可靠度,继而评估加固梁的服役年限。结果表明:混凝土梁抗剪可靠度随服役时间在早期呈现缓慢下降,而后期呈线性快速下降的趋势;加固梁相比未加固梁,可靠度有一定程度的提高。抗剪梁在达到80%的服役基准期之后,采用侧面内嵌CFRP技术进行加固,可以延长梁体的抗剪服役寿命,约为服役基准期的8%。Abstract: In order to evaluate the impact of environmental effects on the shearing reliability of reinforced concrete (RC) beams strengthened with side near surface mounted (SNSM) carbon fiber-reinforced polymer (CFRP), the time-varying function model of the shear bearing capacity of the strengthened beams considering environmental impacts was established. Then, based on the JC method, the time-varying shear reliability of RC beams with different ratios of standard values of dead load and live load before and after reinforcement was calculated, and then the service life of the strengthened one was evaluated. The results showed that the shear reliability of RC beams decreased slowly with the increase of service time in the early stage, and decreased rapidly and linearly in the later stage. Compared with unstrengthened beams, the reliability of strengthened beams had been improved to a certain extent. When the RC beams were serviced 80% of the base period, its shear reliability could continue to be serviced about 8% of the base period after strengthened with SNSM CFRP technique.
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