竖向荷载作用下碳纤维布加固损伤框架试验研究

为了分析碳纤维布加固对损伤钢筋混凝土框架结构的受力性能的影响,按1:3缩尺模型设计了用碳纤维布加固的损伤钢筋混凝土框架结构的试验试件,进行竖向荷载作用下的试验研究分析。试验结果表明,对损伤混凝土结构较大裂缝进行灌胶密闭和粘贴间距较小的U型箍能够有效抑制已有裂缝开展;梁底粘贴碳纤维布在粘结锚固满足的情况下,不仅能够有效延缓钢筋的屈服,而且可以大幅度提高梁的极限抗弯承载力。碳纤维布加固后的梁的拉力由钢筋和碳纤维布共同承担,钢筋屈服后碳纤维布的作用明显增大,承担其主要拉力,为防止碳纤维布突然拉断,需考虑其有效利用率问题。

Experimental investigation of damaged frame strengthened with CFRP under vertical load

In order to study how the strengthening method affects its performance,the test model of damaged RC frame structures strengthened with CFRP were designed with the scale 1:3;and experimental investigation under the vertical load would be carried out in this paper.Based on the test results,the original cracks were restrained by means of filling the structural adhesion into the crack of damaged concrete structure and plastering the close-spaced "U" shape CFRP stirrup.On condition of better bond,CFRP cannot only postpone steel bar yielding,but increase the ultimate flexural capacity greatly.Both CFRP and steer bar take on loads together,and CFRP assumed the loads more and more after the steel bars yield.Above all,the load is taken on mainly by CFRP when the steel bar drawn on ultimate strength,but the whole strength of CFRP cannot be fulfilled.