Studies on Reinforced Concrete Inverted Umbrella Hyperbolic Paraboloid Shells

Abstract

Hyperbolic paraboloid shell roofs have been extensively used in construction because of impressive appearance and economy in cost. For wide spans, the cost of form work is generally high. By reusing this form work we can reduce the cost of construction. These shells require special care in laying reinforcement, concrete pouring and compaction and hence the labour required for this type of construction is highly skilled. In this study, the design of inverted umbrella type hyperbolic paraboloid shells have been done using IS 2210 - 1988 code and IS 456-2000 code. Concrete of grade M30 and Steel of grade Fe500 are used throughout the investigation. The central dip is taken as variable and it will be taken as a/3, a/4 and a/5. In this study, 21 inverted umbrella type reinforced concrete hyperbolic paraboloid shells have been designed and the estimation of cost has been done. The effect of central dip on the cost per sq.m covered investigated for the inverted umbrella shells.