Experimental Study And Finite Element Analysis Of L-shaped Concrete-filled Composite Steel Tubular Columns

Special-shaped concrete-filled steel tubular columns not only have the merits of concrete-filled steel tubular columns, but also can avoid the appearance of edge angles in the room, are benefit for the layout of building and increasing the utilization area of building, because of this, the special-shaped concrete-filled steel tubular columns have good application prospects and more and more scholars are attracted all around the world. The experimental study and non-linear finite element analysis on the earthquake resistant capability of L-shaped concrete-filled composite steel tubular columns considering the influencing factors of cross-section type, thickness of steel tube, ratio of axial compression stress to strength, concrete strength, have been finished. According the analysis we can get the following conclusions:1. When the thickness of steel tube increase the bearing capacity of specimens increase, but cross-section type, ratio of axial compression stress to strength, concrete strength do not have palpable effect to bearing capacity.2. When the thickness of steel tube increase the stiffness and bearing capacity of specimens which have same cross-section type increase. The stiffness and bearing capacity of the specimens with same thickness of steel tube are nearly same, but the effect of cross-section type, ratio of axial compression stress to strength, concrete strength to bearing capacity do not have palpable rule.3. The shapes of hysteresis curves of all specimens are full and fusiform, the displacement ductility factors are greater than 2.36, the equivalent viscous damping factors are greater than 0.17, so the specimens have good earthquake resistant capability.4. The skeleton curves got by calculated results of finite element are consistent with the one got by experimental results basically. The specimens'general stiffness, largest bearing capacity and the trend of stiffness change got by calculated results and experimental results are basically the same, but the skeleton curves got by experimental results have falling stage, the one got by experimental results do not have.5. The calculated results and experimental results are compared. The results indicate that the calculated results of finite element are consistent with the experimental results basically. This also shows that the constitutive models of steel and concrete, the finite element model, the solving method, the setting of parameters and so on are reasonable and the calculated results of finite element are reliable.