COMPUTER AIDED DESIGN OF WAFFLE SLAB FLOOR SYSTEM

Abstract

Structural floor systems such as slab-beam, Plate, Flat slab, waffle slab and grid floor are used to provide level surface over varying shapes and sizes of floor plans. It is pertinent to select a floor system structurally most suitable over a given floor Waffle slab appears to be advantageous for floor plans square in shape in the span range of 6 to 8 m. This aspect has been studied in depth with regard to analysis and desing of waffle slab floor system. Waffle slab structurally can be treated as system of interconnected webs topped by a thin slab. Webs are closely spaced and small in cross-section so that the entire floor may still be categorized as a slab with wffers located in a certain visually attractive pattern. In this forms, waffle slab can be anslysed as a grid floor under transverse loading. The floor may be just placed over a system of load bearing walls and hence providing simple support conditions or framed into a system of RC columns through edge beams in which case floor moments get substantially relocated between mid-span and edge beams. There is also a trade off between the web spacing and web cross-sectional sizes. These aspects have been investigated in depth to finally arrive at the structurally most efficient web size and spacing fop diferent floor plans. The analysis has been done using a computer programme bassed on stiffness method. The design has also been done a computer programme spacially developed for this purpose. The relevant conclusions arrived at are discussed and reported in the dissertation.