Bearing Load Calculator Formula
Understand the math behind the bearing load calculator. Each variable explained with a worked example.
Formulas Used
Bearing Pressure
bearing_pressure = f_n / bearing_areaVariables
| Variable | Description | Default |
|---|---|---|
force | Applied Force (F)(kN) | 80 |
bearing_area | Bearing Contact Area (A)(mm^2) | 4000 |
f_n | Derived value= force * 1000 | calculated |
How It Works
Bearing Pressure
Bearing pressure is the compressive contact stress between two surfaces, such as a beam sitting on a support plate.
Formula
sigma_b = F / A_bearing
where F is the applied force and A_bearing is the contact area. This must not exceed the allowable bearing stress of the weaker material. For steel on concrete, allowable bearing is typically 0.85 f'c (concrete strength) multiplied by area modification factors.
Worked Example
An 80 kN beam reaction on a 100 mm x 40 mm bearing plate.
force = 80bearing_area = 4000
- 01Bearing area = 100 x 40 = 4000 mm^2
- 02F = 80 kN = 80,000 N
- 03sigma_b = 80,000 / 4,000 = 20 MPa
Ready to run the numbers?
Open Bearing Load Calculator