Two-Way Shear Strength.
Two-Way shear strength of two-way members is calculated automatically
İnternational Design Codes
ACI 318-19 : Two-Way Shear Strength
TSC 2018 : Punching Shear Stress at Critical Section (7.11.8)
Notation in ACI 318-19
Av = area of shear reinforcement within spacing s, in.2
bo = perimeter of critical section for two-way shear in slabs and footings, in.
d = distance from extreme compression fiber to centroid of longitudinal tension reinforcement, in.
db = nominal diameter of bar, wire, or prestressing strand, in.
fc ' = specified compressive strength of concrete, psi
√fc‘ = square root of specified compressive strength of concrete, psi
fyt = specified yield strength of transverse reinforcement, psi
vc = stress corresponding to nominal two-way shear strength provided by concrete, psi
vn = equivalent concrete stress corresponding to nominal two-way shear strength of slab or footing, psi
vs = equivalent concrete stress corresponding to nominal two-way shear strength provided by reinforcement, psi
vu = maximum factored two-way shear stress calculated around the perimeter of a given critical section, psi
αs = constant used to calculate Vc in slabs and footings
β = ratio of long to short dimensions; clear spans for two-way slabs, sides of column, concentrated load or reaction area; or sides of a footing
ϕ = strength reduction factor
λ = modification factor to reflect the reduced mechanical properties of lightweight concrete relative to normalweight concrete of the same compressive strength
λs = factor used to modify shear strength based on the effects of member depth, commonly reffered to as the size effect factor
Nominal shear strength of the two-way members with and without shear reinforcement is calculated by using Codes.
Critical Sections for Two-way Members