Horizontal Shear

Interface shear reinforcement shall be considered across a given plane at an interface between dissimilar materials or an interface between two concretes cast at different times (precast and deck), as per LRFD Art. 5.8.4.

Based on the PCI Design Handbook (References), the horizontal factored shear force per unit area of interface is calculated as follows:

V u h = \frac{V u}{d v b v}

where:

V_u = Factored vertical shear force at specified section (total)

d_v = Distance between resultants of tensile and compressive forces

bv = Interface width

Cohesion factors and friction factors considered internally in Precast/Prestressed Girder are as per LRFD Art. 5.8.4.3:

Surface intentionally roughened, c = 0.28, m = 1.0, K₁ - 0.3, K₂ = 1.8
Surface not intentionally roughened, c = 0.24, m = 1.0, K₁ = 0.25, K₂ = 1.5

Horizontal shear reinforcement may be provided in the form of single bars, multiple leg stirrups, or vertical legs of welded wire reinforcement. The minimum horizontal shear reinforcement is as specified in Eq. 5.8.4.1-4 and 5.8.4.1-5.