Research On Static Behavior Of T-shaped Concrete-filled Steel Tube Compound Columns

With the fast development of economy, the massive high-rise residential buildings has been constructed, bottom column of the high-rise residential buildings are subjected to great axial-compression. As the restriction of axial compression ratio, if we still adopt reinforced concrete special-shaped column, the section dimension of it will very big. It not only has negative impact on using, but also lead to the phenomenon of short-column that doesn't contribute to the earthquake-resistance of construction, reinforced concrete special-shaped column has dose not meet the requirements. This paper brings forward a new type of composite column based on reinforced concrete special-shaped column,concrete filled steel tube,Concrete-filled steel tube compound .This composite column has merits of that three types ofcolumn, that make concrete special-shaped column used widely, it has importanct significance.This subject study team makes an experimental work for three T-shaped concrete-filled steel tube compound columns with different diameter of steel tube subjected to axial-compression, to research the different diameter of steel tube have influence on mechanical properties of T-shaped concrete-filled steel the compound columns subjected to axial-compression. This paper introduces the courses of samples making and loading and describes the phenomenon,failure mechanism,resules that of test detailedly. This subject study team as well as simulates three T-shaped concrete-filled steel tube compound columns with different diameter of steel tube subjected to axial-compression by ANSYS and gained the limited load-bearing capacity,load-longitudinal displacement curves,stress and strain nephogram of inner and outer concrete of steel tube. Contrast limited load-bearing capacity of teste to simulate. This paper simulates T-shaped concrete-filled steel tube compound columns subjected to axial-compression, when slenderness ratioλ=2,3,4,5,6,7,8,9,10,and thickness of steel tube t=2mm,3mm,4mm,5mm. This paper also simulates T-shaped concrete-filled steel tube compound columns subjected to unilateral eccentric compression and bidirectional eccentric compression when eccentricity is 10mm,20mm,30mm,40mm,to research slenderness ratio,thickness of steel tube have influence on mechanical properties of T-shaped concrete-filled steel the compound columns subjected to axial-compression and eccentricity have influence on mechanical properties of it subjected to eccentric compression. It gained the limited load-bearing capacity,load-longitudinal displacement curves,load-longitudinal strain curves and load-circular strain curves of inner and outer concrete and analysed them detailedly.This subject study team adopts experiment and finite element simulation validate that it is feasible and credibility to simulate the limited load-bearing capacity of the T-shaped concrete-filled steel tube compound columns by finite element software; The bigger diameters of steel tube, the bigger limited load-bearing capacity of specimens; in the scope of research, It is found that limited load-bearing capacity of the T-shaped concrete-filled steel tube compound columns doesn't present any corresponding relationship with slenderness ratio,but limited displacement are increasing along with the slenderness ratio; the thickness of steel tube have not influence on lmited displacement of it subjected to axial-compression,however,the more the thickness of steel tube,the more limited load-bearing capacity; the limited load-bearing capacity and the lmited displacement of T-shaped concrete-filled steel compound columns subjected to eccentric compression are falling along with eccentricity are increasing, however, transverse flexibility are increasing.