Axial Capacity Prediction of Concrete-Filled Steel Tubular Short Members Using Multiple Linear Regression and Artificial Neural Network

The estimation of the ultimate capacity of rectangular or circular shaped steel tubular members filled with concrete, such as columns, beams, and beam-column connections, requires a detailed structural study to be carried out. Therefore, identify the concrete strength the member subjected to axial-load only. Using the Levenberg-Marquardt artificial neural network, this paper investigates the concrete-filled steel tubular (CFT) members axial strength. 201 experimental specimens were collected from the literature to obtain the best results, and a wide range of geometric and material properties of CFT members were included. The proposed design and specimens illustrate the practicality and effectiveness of the chosen CFT column approach to classify real structural results.

Axial Compression Behaviour of Concrete-Filled Double-Layer Steel Tubular Column

<p>Nowadays, height of supertall buildings with height over 300 meters have been successively renewed in the world. To improve the global stability of the supertall building, mega-columns with excellent seismic, wind-resistance and axial compressive performance are recommended to be set in its perimeter. Concrete-filled double-layer steel tubular column (CFDLT column) transforming from the concrete-filled double-skin steel tubular column (CFDST column) by filling the hollow part of cross-section with concrete was proposed by the author. In this study, axial compression tests of CFDLT column, CFDST column and conventional concrete-filled steel tubular column (CFT column) specimens were carried out to investigate the axial compression behaviour of them. The experimental results showed that the CFDLT column specimen exhibits higher axial compressive strength and larger energy dissipation capacity than the CFDST column and the conventional CFT column specimens. It was found that the axial stiffness of CFDLT column degrades slower than that of the conventional CFT column right after the peak load. And, it is expected that the CFDLT column can be used as a mega-column in the tomorrow’s supertall buildings.</p>

Numerical study on multi-cell CFT column under lateral force in different direction

<p>To meet the demand of structural performance of the tomorrow’s supertall buildings, multi-cell CFT column with double-layer circular steel tubes was proposed. In this study, numerical studies on the multi-cell CFT column with double-layer circular steel tubes under lateral force in two different directions are carried out to investigate the effect of loading direction on the inelastic behavior of this kind of column. The results show that there are no significant differences in the initial flexural stiffness and flexural strengths of the proposed multi-cell CFT column with double-layer circular steel tubes between the two different loading directions.</p>