DESIGN GUIDANCE FOR OPTIMUM DIMENSIONS OF SINGLE PANEL SOLID SLABS

Civil Engineering Department, Faculty of Engineering at El-Mataria,

Helwan University, Cairo, Egypt

Standard codes of practice give minimum and maximum limits for concrete and steel reinforcement

dimensions in order to satisfy serviceability and ultimate limits. However, there exist optimum

dimensions for concrete and steel reinforcement that not only satisfy the code provisions but also they

give minimum cost of a structure. The main aim of this research is to provide the design engineer with

guidance in the form of tables and simple equations to calculate the optimum slab thickness and

corresponding steel reinforcement ratio for square simply supported solid slabs. A computer program

using FORTRAN language is developed and devoted for design of proposed slabs according to

BS8110 Standard code of practice. The influence of span length, bar diameter and bar spacing on slab

thickness and area of steel reinforcement is investigated. Slab thickness determined from the span /

effective depth ratio given in the code is found to represent adequately the optimum thickness. Using

the optimization technique, the cost of concrete can be decreased to more than 10% whilst that in steel

may be reduced to 75%.