Ashok K. Ahuja

Influence of Cross-Sectional Shapes on Wind Loads on Tall Buildings

Present paper describes the details of the experimental study carried out on the models of tall buildings with varying cross-sectional shapes under both standalone condition as well as interference condition. Two cross-sectional shapes namely square and triangular are considered. Both force and pressure measurements are made on the models. Rigid models of tall buildings are made of timber for force measurement and of Perspex sheet for pressure measurement. The models are tested in an open circuit boundary layer wind tunnel. Twisting moment developed due to wind is measured in addition to base shear and base moment in along-wind direction as well as across-wind direction. Effect of wind incidence angle on wind loads is studied in case of isolated condition. In case of interference condition, effect of distance between object building and interfering building on wind loads is studied.

Computational study on performance of circular concrete filled steel tubular columns

The structural behaviour of circular concrete filled steel tubular (CFST) columns with different geometries and filled with different grades of concrete, have been investigated analytically using the numerical results of three dimensional non-linear finite element model, which has been developed using commercial finite element code ANSYS. The steel tubes were having different lengths, diameters, and thicknesses, while the concrete cores were having different compressive strength. The study is focused on the parameters that include: steel tube thickness (t), outer diameter of steel tube (D), ratio of D/t and grade of concrete core. Effects of these parameters on the axial load carrying capacity and corresponding strain have been investigated. To comment on the performance, two parameter; confinement index and concrete enhancement factor are formulated, presented, and discussed.