Punching shear resistance of a slab without shear reinforcement, v_Rd,c

The punching shear resistance of a slab should be assessed for the basic control section (see Figure 6.12). The design punching shear resistance [MPa] may be calculated as follows:

where:

f_ck

is the characteristic compressive strength of concrete, see Table 3.1

k

= 1 + √200/d   ≤ 2,0
where d is the effective depth, in [mm]

ρ_l

= (ρ_ly⋅ρ_lz)^1/2   ≤ 2%
ρ_ly, ρ_lz are longitudinal reinforcement ratios in y- and z- directions respectively. Their values should be calculated as mean values taking into account a slab width equal to to column width plus 3d each side

σ_cp

= (σ_cy + σ_cz)/2,
where σ_cy, σ_cz are the normal concrete stresses in the critical section in y- and z- directions (in [MPa], positive if compression):
σ_cy = N_Ed,y / A_cy and σ_cy = N_Ed,z / A_cz
  N_Ed,y, N_Ed,y are the longitudinal forces across the full bay for internal columns and the longitudinal force across the control section for edge columns. The force may be from a load or prestressing action.
  A_cy, A_cz are the areas of concrete according to the definition of N_Ed,y, N_Ed,y respectively

C_Rd,c

is a Nationally Determined Parameter, see § 6.4.4 (1)

v_min

is a Nationally Determined Parameter, see § 6.4.4 (1), or (6.3N) for the calculation of v_min following the Eurocode recommendation

k₁

is a Nationally Determined Parameter, see § 6.4.4 (1).