Background Knowledge - Strengthening Design of Reinforced Concrete with FRP - page 24

ρ w = 2%

2.50

V c (max) = 3.5
f c b w d √

2.40

ρ w = 1%

2.30

V c

2.20

√ f c b w d

ρ w = 0.5%

2.10

Eq. (2-27)

2.00

f c = 3000 psi
f c = 5000 psi

1.90

0 0.25 0.50

V u d / M u

0.75 1.00

FIGURE 2.14 Concrete shear strength for shear and flexure only. (Courtesy of Portland
Cement Association [2013].)

* Based on a 6" × 12" beams with d = 10.8"

Eq. (2-32)

6

5

V c
f c b w d

Range of values *
obtained by

√

4

Eqs. (2-30) and (2-31)

3

2

Eq. (2-33)

Eq. (2-29)

f c = 5000, ρw = 0.005,
a / d = 5

1

Compression Tension

1000 750 500 250

N u
A g

0 -250 -500

(psi)

FIGURE 2.15 Concrete shear strength for shear, flexure, and axial force. (Courtesy of
Portland Cement Association [2013].)