How Ast provided for footing is calculated?


Applies To
Product(s):STAAD Advanced Concrete Design
Version(s):Connect Edition
Environment:
Area:Concrete Design
Subarea:Footing Design
Original Author:Suvadeep Acharjee, Bentley Technical Support Group

As per design, required reinforcement is 1478/1528 sqmm along L/B direction. Provided reinforcement is T12@175 mm which amounts to 1453 sqmm only for 2.25 m width of footing, whereas the calculation report shows Ast provided as 1583sqmm. Please clarify.

Width = 2250 mm Ast required = 1478 sqmm Reinforcement provided = T12@175 mm In RCDC the number of bars required are calculated and spacing is calculated. While presenting the spacing rounded to 5 mm. In this example, number of bars as per spacing would be calculated as below – (2250 / 175 = 12.86 which is 13 spaces). Hence number of bars would be 14. Thus actual Ast-provided would be (14x113.097 = 1584) 1584 sqmm which is more than required.