Design parameters for horizontal bars (concrete wall: ACI 318)
For some of the horizontal bar parameters, additional user defined limits can be applied - where this is the case minimum and maximum values are specified in Design Options > Wall > Reinforcement Layout
Minimum and Maximum Reinforcement Area
The code provisions which control the horizontal reinforcement area are,
- Limiting minimum ratio of horizontal reinforcement area to gross concrete area, rh,lim,min
- Limiting maximum ratio of horizontal reinforcement area to gross concrete area, rh,lim,max
The controlling values are:
IF dbv ≤ No. 5 (No. 16) with fy ≥ 60,000 psi (420 MPa) OR WWR ≤ W31 or D31
THEN ρh,lim,min = 0.002 ELSE 0.0025 for all other deformed bars
Total minimum area of horizontal reinforcement, As,min = ρh,lim,min*Acg
Total maximum area of vertical reinforcement, As,max = ρh,lim,max*Acg = 0.08*Acg
where Acg= Gross area of the concrete wall.
You can select a minimum ratio which will be the start point for the design in Design Options > Wall > Reinforcement Layout.
Minimum and Maximum Horizontal Bar Spacing
This is identical in principle to min vertical bar spacing.
Minimum and Maximum Confinement Bar Spacing
There are Code provisions that control the maximum spacing:
The recommended values are,
Limiting maximum transverse spacing, sw,lim,max = min (16*dbv , 48*dbw , hw)