碳纤维增强复合布加固混凝土圆柱受压承载力试验与数值模拟

Experimental and numerical simulation of load bearing capacity of concrete columns strengthened with CFRP sheets

[目的]对不同层数碳纤维增强复合(CFRP)布加固混凝土圆柱进行轴心抗压试验的破坏分析以筛选出最优层数,并在此基础上对混凝土强度及长细比参数作进一步分析.[方法]采用万能试验机对不同层数CFRP布加固混凝土圆柱试件进行轴压试验,同时利用ABAQUS非线性有限元软件进行模拟验证及参数分析.[结果]轴压试验结果的极限承载力及荷载-位移曲线表明,CFRP布加固混凝土圆柱对于提升混凝土的抗压承载力具有明显效果,同时对于C30混凝土而言,两层CFRP布的加固效果最优.有限元模拟结果得出随着混凝土强度的提升,CFRP布的加固效率降低;当长细比大于2∶1时,CFRP布加固混凝土圆柱对于偏心受压时极限承载力的提升较小.[结论]本文通过对不同层数CFRP布加固混凝土圆柱试件进行轴压试验分析,筛选出了最优加固层数.同时提出了相应的有限元模型,其与试验结果吻合良好.基于有限元模型对混凝土强度及试件长细比参数进行充分分析,为CFRP布加固混凝土圆柱在实际工程应用中提供了参考依据.

[Objective]The destructive analysis of concrete columns strengthened with different layers of CFRP through axial compression tests is carried out to select the optimal number of layers,and based on this,further analysis is conducted on the parameters of concrete strength and slenderness ratio.[Methods]The universal testing machine is used to conduct axial compression tests on concrete column specimens strengthened with different layers of CFRP,while the commercial finite element software,ABAQUS,was used for simulation verification and parameter analysis.[Results]The results of the axial compression tests,including the ultimate load bearing capacity and load-displacement curve,indicate that the CFRP sheets has significant effect on improving the compressive capacity of concrete,especially for C30 concrete with the two layers reinforcement.The finite element simulation results show that the strengthening efficiency of CFRP sheet decreases with the increase of concrete strength;when the slenderness ratio is more than 2∶1,the CFRP sheets have little effect on the ultimate load bearing capacity of CFRP reinforced concrete columns when subjected to eccentric loading.[Conclusions]Through the analysis of axial compression tests on concrete column specimens strengthened with different layers of CFRP,this paper has identified the optimal number of reinforcement layers.At the same time,corresponding finite element models have been proposed,which show good agreement with the experimental results.Based on the finite element models,a comprehensive analysis of concrete strength and specimen slenderness ratio parameters has been conducted,providing a reference basis for the practical engineering application of CFRP-reinforced concrete columns.