加载方式对钢管自密实混凝土加固RC圆柱受力性能影响的研究

将实际工程中钢管自密实混凝土加固柱的加载方式归纳成非对称加载、全截面加载、荷载仅施加于混凝土等3种。进行这3种加载方式对钢管自密实混凝土加固RC圆柱受力性能影响的试验研究,并采用ABAQUS有限元软件对加固柱的荷载-变形曲线进行数值仿真分析,计算结果与试验结果吻合良好。通过ABAQUS有限元软件分析在后浇自密实混凝土强度、钢管壁厚以及钢管屈服强度不同参数影响下,3种加载方式对加固柱受力性能的影响。结果表明:非对称加载和荷载仅施加于混凝土上时,钢管后期横向应力远大于全截面加载方式,套箍作用更明显;增大钢管壁厚和钢管屈服强度能改善加固柱延性,但对全截面加载方式延性改善最为明显;加载方式主要影响试件的套箍作用、刚度以及延性,对承载力提升不明显。

Research on influence of loading method on behavior of cricular RC columns strengthened with self-compacting concrete filled steel tubes under axial loads

The experimental research has been made to study the behavior of specimens under different loading conditions,which include the steel tube and core concrete to be simultaneously loaded,only the core concrete to be loaded,one end of the steel tube and core concrete to be simultaneously loaded,and another one end of the core concrete to be loaded.At the same time,the finite element method is used to analyze the behavior of three kinds of loading methods to strengthen the specimen for stress analysis.The effects of the parameters of the strength of the poured concrete,the thickness of the steel pipe,the yield strength of the steel.The results show that the specimens loaded with core concrete can exert a hoop effect on the steel tube of initial coat,and still provide stable lateral restraint force after yielding and concrete crushing.For the three loading conditions,the bearing capacity of speciments are basically the same,but it should be higher than the simple superposition of the bearing capacity of steel and concrete.The loading method mainly affects the hoop function,stiffness and ductility of the specimens.