通过4根短柱(1根RC方柱和3根钢管自密实混凝土加固柱)的偏心受压试验,研究外套钢管自密实混凝土加固法对RC方柱承载力和延性性能的影响,结果表明加固后RC柱的承载力与延性得到大幅提高,且加固柱的承载力随偏心距的增大而减小。为进一步研究钢管壁厚和后浇混凝土强度对加固效果的影响,采用了通用有限元软件ANSYS对加固偏压柱的受力全过程进行了计算分析。经验证,计算所得试件的荷载-变形曲线与试验结果吻合良好。在此基础上对加固柱进行参数分析研究,研究结果表明:偏心距对加固偏压柱的承载力影响最为明显,其次是钢管壁厚,自密实混凝土强度的影响较小。
One reinforced concrete column and three retrofitting columns subjected to eccentric loading have been presented.The experimental results shows that the use of self- compacting concrete filled steel tubes is interesting since the ductility and the bearing capacity of the RC columns are greatly improved,and the ultimate bearing capacity is decreased with the increase of the eccentricity.In order to further investigate the effect of the thickness of the steel tubes and the concrete strength on the eccentric loading behavior of the strengthened columns,a finite element(ANSYS) analysis is employed to analyze the loading process of the retrofitting columns subjected to eccentric loading.It is found that the calculations of load- deformation curves agree well with the experimental results.On this basis,the influence of some parameters including the thickness of the steel tube the concrete strength and the eccentricity on the ultimate bearing capacity of the retrofitting columns is analyzed.The study shows that the influence of the eccentricity is obvious,the thickness of the steel tube is less and the concrete strength is the least.