DESIGN OF REINFORCED CONCRETE CIRCULAR SLABS BY TWO-WAY ISOTROPIC STRAIGHT JOISTS

This research introduces a new simple, efficient, and practical procedure to design the reinforced concrete (RC) circular slabs which have large diameters. The principal idea of this paper concerns to use the isotropic perpendicular RC straight joists to resist the external load. The yield-line theory was adapted to analysis the circular waffle slabs. The steps of design were according to the ACI Code provisions. Fixed and simply supported circular slabs were presented. Closed form equations have been driven by author for the purposes of analysis and design this type of slabs by the present procedure. Uniformly distributed load was considered, that represent almost practical cases. Useful illustration example is presented in this study according to the available materials in Iraq to facilitate the job of designers. The good performance of RC circular slab which design by the present procedure proved clearly the efficiency of this technique