FALL 2013

 

Numerical and Experimental Analysis of Tall Buildings

by

Bushra Marium Islam

 

Numerical and experimental analyses are performed on tall buildings under lateral loading. Static lateral loading is used to observe the deflection of tall buildings; 60- and 90-storied tube and diagrid systems (scale 1:120) for the entire work. Basic models of these two systems are observed to see how tall buildings deflect under lateral static loading. ETABS is used for the numerical analysis and six tall building models (four 60-storied, two 90-storied) are constructed for lab experiments. The loading arrangements are also constructed and all tall building models are experimented with the loading arrangement. There are several parametric studies done by ETABS to stimulate the experimental results to observe how the interior columns effect deflections of tall buildings. The results for numerical and experimental analysis are compared under different conditions, for two different structural systems (tube and diagrid) and also for deflection at different heights.

Except in a few cases, the numerical results do not match the experimental results too well in general, the worst scenarios being for the 90-storied structures. The basic diagrid system performs better compared to the basic framed tube system studied here. The parametric studies show that the interior columns do not increase the structural stiffness (of the tube or diagrid system) significantly.

The set up of structural models and lateral static load arrangement in the lab prove to be a challenge due to the complexity of the structures as well as the support system. The various efforts attempted in this work can be of help for future research on tall buildings.