Pub. Date | : Jul, 2020 |
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Product Name | : The IUP Journal of Structural Engineering |
Product Type | : Article |
Product Code | : IJSE30720 |
Author Name | : Pavan Gudi, Sujay Deshpande, Sachin R Kulkarni, K P Thejaswi |
Availability | : YES |
Subject/Domain | : Science and Technology |
Download Format | : PDF Format |
No. of Pages | : 14 |
Concrete Filled Steel Tubes (CFST) consist of concrete filled inside the hollow steel tubes. The steel section acts as external reinforcement to concrete, thereby strengthening the section by increasing its resistance to shear, bending and torsion. The parameters such as material properties, geometry such as slenderness, D/t ratio, loading, boundary conditions and the degree of concrete confinement decide the performance of the CFST. As the load on a CFST column gradually increases, concrete and steel undergo changes in the lateral expansion. At lower strains, steel expands at a faster rate than concrete. At higher loads, steel transfers its longitudinal load to concrete and the expansion of concrete exceeds the expansion of steel due to change of stress from uniaxial to biaxial. The radial pressure induces hoop tension in the tube changing the state of stress from uniaxial to biaxial in the steel tube and from uniaxial to triaxial in concrete. A nonlinear Finite Element (FE) model is developed using the FE software package ANSYS to determine the ultimate load and axial deformation for circular, square and rectangular sections for different grades of infilled concrete.
Concrete Filled Steel Tube (CFST) is a composite material which is being increasingly used nowadays in the construction of buildings. CFST columns can provide excellent seismo-resistant structural properties such as high strength, high ductility and large energy absorption capacity. CFST structures are one of the modifications to combined load-bearing structures known as composite structures. In addition to the enhancement in structural properties, a considerable amount of construction time can be reduced due to the prevention of a permanent formwork. The orientation of the steel and concrete in the cross-section optimizes the strength and stiffness of the section. The steel lies at the outer perimeter where it performs most effectively in tension and in resisting bending. Also, the stiffness of the CFST is greatly enhanced because of the steel which has a greater modulus of elasticity than concrete and is situated farthest from the centroid, wherein it makes the greatest contribution to the moment of inertia.
Composite structures, Concrete Filled Steel Tubes (CFST), Axial Compression, Finite Element Analysis