Differential Settlement in Various Tubular Structural Systems

Abstract

Tubular structural system is a 3 dimensional space structure comprises of 3, 4 or possibly more frames, braced frames or shear walls joined at or near their edges to form a vertical tube like structural system which is capable of resisting lateral forces in any direction by cantilevering from the foundation. Tubular tall building structures have started becoming an integral part of the building scenario in developed countries. They provide various advantages over a conventional tall building in terms of flexibility of interior spacing, better utilization of material and hence lesser cost of construction. Therefore studies on various parameters that influence the serviceability of such structure is beneficial in the long run. One such parameter is the differential settlement of tubular structures is studied under this work. This research work will shed some light on the influence of differential settlement on the tubular structures. The differential settlement that would occur on four separate G+60 tubular tall structures under different framed conditions is determined using a structural analysis and design software and thereby observed that there was a gradual increase from zero at the base of structure in fixed supports whereas in spring supports there was a settlement at the base of structure. From the analysis of different tube structures like framed tube, braced tube, bundled tube and tube in tube structures, it was observed that there was a certain percentage increase in the settlement of top storey with spring support when compared to that of fixed support. Compared to other tube structures, the framed tube structure exhibited a better performance in settlement under both the support conditions.