13.1.1 Maximum and minimum reinforcement
(1) The minimum reinforcement to ensure ductility of members as specified in subclause 5.3.2 to control
cracking (neglecting the prestressing force in prestressed members) shall be calculated using the mean axial
tensile strength of the concrete, fctm, from tables 9 and 10 and taking the stress in the steel, ss, to be equal to fyk.
(2) In prestressed member sections containing two or more bonded tendons, the tendons may be counted
towards the minimum reinforcement (see item (1) above) if these are located at a distance equal to not more than
0,2 h *) or 250 mm (whichever is less) from the reinforcement. The calculations shall assume a stress in the
prestressing steel not greater than fyk.
(3) The minimum reinforcement shall be evenly distributed over the width and proportionately over the depth
of the tension zone. To improve ductility (irrespective of the provisions to accommodate tension), the bottom
minimum span reinforcement shall be continuous between and above the supports. Tendons and reinforcement
continued upwards shall not be taken into account. Above internal supports, a top minimum reinforcement shall
be provided that extends over a length of at least a quarter of each of the two adjacent spans. The top minimum
reinforcement shall be continued over the full length of cantilevers. The reinforcement shall be anchored at the
end support and at the internal support over a length not less than that specified in item (8) of subclause 13.2.2;
joints shall be designed to withstand the full tensile force.
(4) The proportional area of reinforcement in any cross section (including at lap joints) shall be equal to not
more than 0,08 Ac.
(5) Where the x/d ratio in densely reinforced T-beams is greater than specified in item (3) of subclause 8.2, the
minimum reinforcement should consist of links with a diameter not less than 10 mm and taking the maximum
spacing, s max, from line 3 of table 31, unless confinement of the flexural compression zone is achieved by other
means.