Eriksson Pile uses the a simplified shear method as described in PCI BDM 20.9.3.4. This method designs the pile as a traditional reinforced concrete section and includes the shear strength of the concrete and the shear strength of the transverse reinforcement for load cases that result in pile compression. For load cases in tension it is recommended to neglect shear strength of the concrete and reinforce to resist all shear assigned to the pile. In addition to this the values for β, θ, and λ are assumed to be 2.0, 45°, and 1 respectively which should result in a conservative design.
Shear Design
where:
Vn = nominal shear resistance
Vc = nominal shear resistance of the concrete
Vs = nominal shear resistance of the spiral
Vp = component of prestressing force in the direction of the shear force
f’c = concrete strength
bv = effective web width taken as the minimum web width within the depth dv (LRFD Art. 5.7.2.8)
dv = effective shear depth (LRFD Art. 5.7.2.8)
h = pile width
λ = concrete density modification factor
Av = area of transverse reinforcement
fy = transverse yield strength
s = spacing of transverse reinforcement measured in a direction parallel to the longitudinal reinforcement