Calculate bearing capacity from plate bearing test result

A Plate load test is a field test which is used to determine the bearing capacity and settlement of soil.

The calculation of bearing capacity is perfomed using the following steps.

  1. Plotting the load settlement curve
  2. Assessing the failure point on load settlement curve
  3. Calculation of safe bearing capacity
  4. Determining settlement of proposed footing

Calculation of the ultimate resistance of soil (R) using the formula

R = Ultimate resistance of soil in kg

d = Average depth of impression in cm

w = Weight of soil ball in kg

h = Height of fail of soil ball in cm

A = cross sectional area


Therefore the resistance of soil is R/A in kg/cm squared

Safe bearing capacity is R/(A * FOS)

FOS is the Factor of Safety

The FOS will be between 2 to 3 depending on the type of structure and the site conditions.