NONLINEAR ANALYSIS OF WITH AND WITHOUT STIFFENERS OF HOLLOW AND CONCRETE FILLED STEEL TUBE COLUMN BY USING ABAQUS 6.10-1

Abstract

The concrete filled steel tube(CFST) column has got many advantages compared with the reinforced concrete member. Concrete filled steel tube are frequently used for piers, deep foundation, caissons and columns etc because of their high compressive strength and stiffness. Analytical Study of Hollow Steel Tube With concrete filled of different grades and without and with steel stiffeners (one stiffener and two stiffener) under monotonic loading is presented in this Paper. The nonlinear behavior of the columns is observed by using finite element software ABAQUS 6.10-1.the results from non linear finite element analyses is obtained and is verified with experimental tests, Eurocode Part-4 and ACI-318(2005).It was found that the non linear finite element simulations are in a good agreement with the codes of practice and experimental results. this study has carried out to examine the influence of several parameters such as thickness of tube(3mm and 4mm) and stiffener configurations(i,e At 1/3 times of height and 1/2 times of height), frequency , time period and also to find Ultimate load carrying capacity of hollow and composite column on the compressive response under axial load. The hollow and composite columns are extensively developed by considering different configuration of steel stiffeners. The main variables are: (1) number of stiffeners (2) arrangement stiffeners (3) stiffener spacing (4) thickness of steel tube (5) compressive strength of concrete(20MPa, 25MPa, 30MPa) .Effects of above variables mention on the behavior of columns is assessed. Failure modes and deformed shape of the columns is also illustrated. From this study it is concluded that, the developed finite element model gives closer perfection and depicts the non linear behavior well with 5-10% error. Also the non linear behavior is examine when only steel tube is loaded , only concrete is loaded and when both is loaded and the combination of loading on both steel tube and infill concrete gave higher load carrying capacity. The analytical results are well validated with previous researchers too.