Reinforcement ~ generally in the form of steel bars which are used
to provide the tensile strength which plain concrete lacks. The
number, diameter, spacing, shape and type of bars to be used have
to be designed; a basic guide is shown on pages 501 and 502.
Reinforcement is placed as near to the outside as practicable, with
sufficient cover of concrete over the reinforcement to protect the
steel bars from corrosion and to provide a degree of fire
resistance. Slabs which are square in plan are considered to
be spanning in two directions and therefore main reinforcing bars are
used both ways whereas slabs which are rectangular in plan
are considered to span across the shortest distance and main bars are
used in this direction only with smaller diameter distribution bars placed
at right angles forming a mat or grid.
Simply Supported RC Slabs