• Maximum spacing, s, of deformed longitudinal reinforcement is controlled automatically.

  • The minimum specified concrete cover for nonprestressed cast-in-place slabs is determined automatically according to Table 20.5.1.3.1.


Flexural reinforcement spacing

Concrete cover for reinforcement is determined according to 20.5.1. The minimum specified concrete cover for nonprestressed cast-in-place slabs is determined according to Table 20.5.1.3.1.

Development lengths of deformed reinforcement is determined according to 25.4. Detailed information: Development of Reinforcement.

Splices of deformed reinforcement is determined according to 25.5 Detailed information: Splices. Minimum spacing of reinforcement s, is determined according to 25.2. Detailed information: Minimum Spacing of Reinforcement.

Maximum spacing, s, of deformed longitudinal reinforcement is the lesser of 2h and 18 in. at critical sections and the lesser of 3h and 18 in. at other sections.

Corner restraint in slabs

At exterior corners slabs edge walls or where one or more edge beams have a value of αf greater than 1.0, reinforcement at top and bottom of slab are designed to resist Mu per unit width due to corner effects equal to the maximum positive Mu per unit width in the slab panel.

Factored moment due to corner effects, Mu, is supposed to be about an axis perpendicular to the diagonal from the corner in the top of the slab and about an axis parallel to the diagonal from the corner in the bottom of the slab.

Flexural reinforcement in nonprestressed slabs

If a slab is supported on columns, walls and spandrel beams, reinforcement anchorage’s to a discontinuous edge provide the rules below:

  • Positive moment reinforcement extends to the edge of slab and have embedment, straight or hooked, at least 6 in. into spandrel beams, columns, or walls

  • Negative moment reinforcement is bent, hooked, or otherwise anchored into spandrel beams, columns, or walls, and is developed at the face of support

Where a slab is not supported by a spandrel beam or wall at a discontinuous edge, or where a slab cantilevers beyond the support, anchorage of reinforcement is permitted within the slab.

Shear reinforcement -stirrups

Single-leg, simple-U, multiple-U, and closed stirrups are used as shear reinforcement. Stirrup anchorage and geometry is determined with 25.7.1. Detailed information: Stirrups.
If stirrups are provided, location and spacing is determined with Table 8.7.6.3.

The shear reinforcement engage longitudinal reinforcement at both the top and bottom of the slab, as shown for typical details in Fig. R8.7.6(a) to (c).