高强钢绞线网加固RC梁抗弯性能的数值分析

摘要

以河北沧州某大桥加固工程为背景,在高强不锈钢绞线网-渗透性聚合物砂浆加固的T形钢筋混凝土梁抗弯试验研究基础上,采用有限元程序对其进行数值分析,研究混凝土强度、原梁纵筋配筋率、钢绞线用量、二次受力等因素对加固性能的影响.分析结果表明:加固构件屈服承载力、极限承载力和屈服挠度随混凝土强度、原梁纵筋配筋率、高强钢绞线用量的提高而有所增长,但极限挠度有所降低,构件延性变差;二次受力加固构件以首次受荷发生屈服为界限,未屈服构件受持载程度影响不大,而屈服构件随持载程度增大,力学性能得到较大提升;加固构件最终破坏的模式受纵筋配筋率、钢绞线用量、混凝土强度等因素的影响而有所区别.%Based on the tests conducted to investigate the fiexural behavior of strengthened reinforced concrete (RC) T-beams with stainless steel wire mesh and permeability polymer mortar which took the reconstruction project of a bridge in Cangzhou, Hebei Province as the project background, the finite element program was used to analyze the flexural performance of strengthened T-beams. The influences of concrete strength, longitudinal reinforcement ratio, amount of stainless steel wire and secondary loads on the flexural performance were discussed. The analytical results show that with the increase of the concrete strength, longitudinal reinforcement ratio and amount of high strength stainless steel wire, yield capacity, ultimate capacity and yield deflection are improved, but the ultimate deflection decreases and the ductility of members wanes. The performance of the strengthened members under secondary load is bounded by which can yield under first load or not. If it could not yield before strengthening, the influence of the magnitude of the first load on the performance of the strengthened members is negligible, otherwise, the performance of the strengthened members is promoted greatly with the increase of the magnitude of the first load. The final failure modes of the strengthened members are affected by the longitudinal reinforcement ratio, the amount of stainless steel wire, concrete strength and so on.