Concrete Shear Friction Calculator
Shear transfer across a concrete interface by shear friction. For one of four interface conditions the tool finds the reinforcement needed across the slip plane for the factored shear and axial force, and checks the interface shear stress against its upper limit.
By Arun Kishore, P.Eng. Updated
Open calculatoropens in a new tabInputs and outputs
| Inputs | Total rebar area crossing the slip plane, Avf (mm²) |
|---|---|
| Area of the slip plane, Acv (mm²) | |
| Factored shear Vf and factored axial force Nf (kN), tension negative | |
| Rebar yield strength fy and concrete strength f'c (MPa) | |
| Angle between rebar and slip plane, α (deg) | |
| Concrete density: normal, semi-low or low | |
| Interface: cast against clean hardened concrete (not roughened, or roughened at least 5 mm), cast monolithically, or anchored to as-rolled steel | |
| Outputs | Cohesion c and friction coefficient μ for the chosen interface |
| Minimum required rebar area, and utilization | |
| Shear stress on the interface, and utilization against 0.25 φc f'c |
Worked example
Worked example coming soon.
Limitations and assumptions
- Cohesion and friction are fixed per interface case: c = 0.25, 0.5, 1.0 or 0 MPa with μ = 0.6, 1.0, 1.4 or 0.6.
- λ = 1.0, 0.85 or 0.75 by concrete density, and φc = 0.65.
- The app does not cite a code clause. Check the calculation against your governing code edition.
These calculators are aids, not a substitute for engineering judgment. Check results independently and against the governing code edition before relying on them.