Shear Friction Capacity (Interface Shear)

This calculation determines the shear friction capacity of concrete at a crack or joint

Code:
US flagACI 318
ϕ_v

Resistance factor for shear

Constraints
min: 0step: 0.01
f_c(psi)

Specified concrete strength

Constraints
min: 0step: 100
f_y(ksi)

Specified reinforcing steel yield strength

Constraints
min: 0step: 1
λ

Concrete density modification factor; 1.0 for normal density concrete

Constraints
min: 0step: 0.01
A_vf(in²)

Area of reinforcing crossing the shear plane

Constraints
min: 0step: 0.01
N(kip)

Axial load; compression positive

Constraints
step: 1
t_s(in)

Slab / member thickness

Constraints
min: 0step: 1
b(in)

Effective width of cross section

Constraints
min: 0step: 1
surfaceType

The type of surface at the interface. If no surface prep has been performed, choose plain. Intentionally roughened surface requires hardened concrete to be cleaned and mechanically roughened to an amplitude of at least 1/4 inch (5 mm). Steel surface requires headed studs. It is not intended for smooth steel-on-concrete joints.

Shear friction in concrete

Calculation Steps:

    Coefficient of friction
    • Surface type = Intentionally roughened
    • μ = 1
    Reinforcing ratio and normal stress
    • p_v

      Reinforcing ratio

    • σ

      Normal stress on the interface

      ksi
    Max permissible shear
    • ϕv_nmax

      Maximum permissible shear stress per ACI 318-19 Cl. 22.9.4.4

      ksi
    • ϕV_nmax

      Maximum permissible shear force

      kip
    Shear friction capacity
    • ϕv_n

      Shear friction stress capacity per ACI 318-19 Cl. 22.9.4.2

      ksi
    • ϕV_n

      Shear friction capacity

      kip
    User Notes: