Wang Bu, Wu Xianhui, Liu Qi, Wu Yueyue, Huang Fei, Xu Linfeng, Wu Xing, Deng Yuanxin
School of Civil Engineering, Chang'an University, Xi'an 710064, China.
Dongying Transportation Development Group, Dongying 257091, China.
Polymers (Basel). 2022 Mar 26;14(7):1347. doi: 10.3390/polym14071347.
To develop feasible carbon fiber reinforced polymer (CFRP) retrofit schemes for the shear strengthening of real three-dimensional reinforced concrete (RC) beam-column joints, a series of parameters in relation to the contributions of the CFRP sheets externally bonded to joint panels was numerically investigated in this study. The parameters include CFRP reinforcement ratio, CFRP layout, transverse beam-to-joint panel width ratio, transverse beam-to-joint panel height ratio, location of transverse beam, and number of transverse beams. Strengthening efficiency, a new dimensionless index, was introduced to evaluate the residual effect of a CFRP-strengthening system weakened by the presence of transverse beams in comparison with the increase in joint shear capacity in relation to the one-way counterpart. The results obtained from 44 nonlinear finite element models, which were calibrated against experimental observations, confirmed the effectiveness of the CFRP strengthening technique with regard to the relatively wide ranges of the parameters. The significant differences among the roles of the parameters were revealed, and the reasons behind the differences were analyzed. Furthermore, the shear mechanism of the CFRP-retrofitted joint panels was discussed with the proposed strut-and-tie model.
为了开发用于实际三维钢筋混凝土（RC）梁柱节点抗剪加固的可行碳纤维增强聚合物（CFRP）加固方案，本研究对与外部粘贴在节点面板上的CFRP片材贡献相关的一系列参数进行了数值研究。这些参数包括CFRP配筋率、CFRP布置方式、横梁与节点面板宽度比、横梁与节点面板高度比、横梁位置以及横梁数量。引入了加固效率这一新的无量纲指标，以评估与单向对应情况相比，由于横梁的存在而削弱的CFRP加固系统的残余效应与节点抗剪承载力增加之间的关系。通过44个非线性有限元模型（这些模型已根据实验观测进行校准）得到的结果，证实了CFRP加固技术在相对较宽的参数范围内的有效性。揭示了各参数作用之间的显著差异，并分析了差异背后的原因。此外，利用提出的拉压杆模型讨论了CFRP加固节点面板的抗剪机理。
