Concrete Shear Strength Vc

V_{c} = 2 λ f_{c}^{'} b_{w} d (ma t h r m p s i) V_{c} = 0.17 λ f_{c}^{'} b_{w} d (ma t h r m M P a)

ACI simplified Vc for beams. φVc with φ=0.75. If Vu > φVc, add stirrups. Av fyt d / s vs Vu − φVc. Units: √f'c with f'c in psi or MPa matching the formula.

$V_{c}$: Concrete shear strength
$b_{w}$: Web width
$d$: Effective depth

Step-by-step solved example

f'c=4000 psi, bw=12 in, d=20 in, λ=1. Vc?

Concrete shear Vc on a beam web b×d.

1. √f'c
√4000=63.25.
2. Vc
Vc=2×63.25×12×20=30 360 lb = 30.4 kip.
$V_{c} = 30.4 kip$

Answer: 30.4 kip

10 practice questions

0/10 correct

1.φ for shear in ACI is

2.If Vu ≤ φVc/2, stirrups

3.λ for normalweight is

4.Vs = Av fyt d / s. To cut s in half

5.Vu is from

6.bw for a rectangular beam is

7.The 2√f'c form uses f'c in

8.Maximum Vs is limited to

9.d is to the

10.One-way slab shear uses