CFRP-钢管混凝土加固RC短柱偏压性能试验

Experimental study on eccentric compression performance of RC short columns reinforced with concrete filled CFRP-steel tube

通过8根碳纤维增强复合材料（CFRP）-圆钢管自密实混凝土复合加固和4根圆钢管自密实混凝土加固钢筋混凝土（RC）方形短柱的受压试验,研究了复合加固RC短柱偏压受力性能,分析了偏心距和CFRP层数对复合加固RC短柱的破坏形态、承载力、刚度和延性的影响.复合加固RC短柱的破坏形态包括端部混凝土的压碎、受压区钢管屈曲和CFRP断裂.加固试件表现出延性破坏特征,达到极限承载力后,仍具有一定的承载和变形能力.随着偏心距的增大,加固试件变形增大;偏心距为20,40和60 mm的试件极限承载力平均降低幅度分别约为25%,37%和42%.随着CFRP层数的增加,加固试件变形减小,延性降低;CFRP层数为1和2的试件极限承载力平均提高幅度分别约为16.2%和39.8%.

Based on the compressive tests of eight reinforced concrete（RC） square short columns reinforced with self-compacting concrete filled circular carbon fiber reinforced polymer（CFRP）-steel tube and four RC square short columns reinforced with self-compacting concrete filled circular steel tube,the behavior under eccentrically compressive loading,and the influence of the eccentricity and the number of layers of CFRP on the failure mode,bearing capacity,stiffness and ductility of the reinforced columns were discussed.The failure modes of the reinforced columns involve the concrete crush at the end of the specimens,the buckling of the steel tube and the fracture of CFRP at the compressive region.The column specimens exhibite a ductile failure.After the ultimate load,there is a certain post-load and deformation capacity.The increase of the eccentricity could increase the deformation of the specimens; as the eccentricity is 20,40 and 60 mm respectively,the ultimate load of the specimens decreases by 25%,37% and 42%averagely.The increase of the number of layers of CFRP could decrease the deformation and ductility of the specimens; as the number of layers of CFRP is 1 and 2 layers respectively,the ultimate load of the specimens increases by 16.2% and 39.8% averagely.