CIVILKITSengineering toolsRun the check
CivilKits/Calculators/Structural/Design/Hong Kong Code/One-way RC slab

structural / design / Hong Kong concrete

Hong Kong RC one-way slab flexure and shear.

Check a one-metre strip of a solid one-way slab using practical bar diameter and spacing inputs, with flexural resistance, minimum steel, spacing, and a concrete-only one-way shear screen.

Current code basis declared

Code of Practice for Structural Use of Concrete 2013 (2020 Edition), with Buildings Department amendments through April 2024. This is a bounded design screen, not a complete slab design.

implemented HK concrete subset

Design the strip, then vary the slab depth and bars.

The screen represents a one-metre-wide, singly reinforced strip. Principal and secondary reinforcement are entered in the same language used on drawings: bar diameter and spacing. The calculation converts that arrangement into area per metre before checking resistance and detailing limits.

Flexural equations

PROVIDED STEELAs,prov = (πφ2/4)(1000/s)
RESISTANCET = 0.87fyAs  ·  x = T/(0.405fcub)  ·  z = min(d - 0.45x, 0.95d)  ·  MR = 0.87fyAsz

Here b = 1000 mm. The screen also applies the declared minimum reinforcement and secondary-steel rules, checks the principal and secondary spacing limits, and reports neutral-axis depth.

Concrete-only shear

For the supplied VEd, the calculator reports the applied shear stress v = VEd/(bd) against the implemented concrete shear capacity and maximum stress screen. No links or shear reinforcement are designed by this page.

Assumptions and limits

  • One-way solid slab strip, one metre wide, with fcu in the bounded 20-45 MPa range and 500 MPa reinforcement.
  • Principal and secondary reinforcement are diameter/spacing arrangements; effective depth d is supplied for the selected layer.
  • Current basis: HK Concrete Code 2013 (2020 Edition), with amendments through April 2024; confirm the project edition and interpretation.
  • No two-way action, punching shear, torsion, concentrated-load distribution, support detailing, anchorage, laps, crack-width calculation, deflection, fire, durability, or shear reinforcement design.