A Review on Bundled-Tube as Structural System in Tall Buildings

The demand of tall buildings has increased over the past one or two decades. Reasons behind the sudden demand is the popularity of tall buildings, tourism, economy of the country, infrastructure boost, science and technological knowledge, etc. Another reason for increase in tall buildings is the availability of land and population emigration of rural to urban. The main issues of tall buildings are shear-lag effect with increase in height, aerodynamic wind effects, seismic hazard, public hesitation. Due to increased shear-lag in tubular tall buildings with increased height, there is a shift in the structural system to more advanced systems like diagrid, buttressed core, outrigger, Mega-tube, etc. In India still some of the buildings are constructed with shear-wall frame system or central core wall system are used. For this purpose, the review paper focuses on the tubed-type system that could possibly replace the traditional shear-wall system for tall buildings in India. Various key issues have been identified in the papers and are mentioned in the review for the tubed type system. The review on the topic creates a sea of opportunities for Indian construction industry, which have been heavily relied on shear-wall type system for buildings. The very thick shear walls (of the order of 450mm to 600mm), length of the order 1.5 to 2m, concrete grade of M40 to M70 becomes uneconomical after certain height of the structure. Emphasis should be to create stable structures with not just focus on material and thickness of members, but also the structural system.