Services / Plate Bearing Tests

Plate bearing tests offer a cost-effective, reliable, rapid assessment of ground strength.


The tests are particularly suited to determining the strength of ground for temporary structures such as crane pads, as well as spread foundations for building slabs, wind turbines, electrical sub stations etc.

  • Crane Pads – A Plate Bearing Test will mimic the load of your crane outrigger, establishing the suitability of the crane pad prior to arrival of the crane. This provides reassurance to the constructor of the pad, demonstrates safety for the crane operators, and provides certification for insurers.
  • Building Foundations – Plate Bearing Tests can be used to establish / confirm the strength of the ground for raft or spread foundations. The testing can provide reassurance if assumptions have been made about ground bearing pressure.
  • Wind Turbines – Most suppliers of small or medium sized turbines will supply a standard foundation design for use with that turbine. A Plate Bearing Test will confirm the strength of the ground, and will therefore confirm the suitability of the standard foundation design. This avoids the need for costly bespoke foundation design work on most sites.
  • Roads / Hardstanding – Plate tests (in particular the 150 mm diameter plate) can be used to simulate the static load of a vehicle. Larger plates can be used to calculate an equivalent California Bearing Ratio (CBR) value.
  • Tanks, Bio-digesters & Rigid Structures – The Plate Bearing Test is particularly useful when constructing tanks, bio-digesters or other rigid structures where cracking caused by movement cannot be tolerated. The test can be used to calculate the modulus of subgrade reaction (springiness) of the soil beneath the tank, to allow suitable remedial measures to be designed.

How It Works

Our plate test site teams have access to a full suite of plates:

  • 150 mm plate – Suitable for concrete / bound hardstanding or for modelling point loads.
  • 300 mm plate – For clayey / fine grained soils.
  • 450 mm plate – For coarse grained soils and for modelling spread loads.
  • 600 mm plate* – For very coarse grained soils and for modelling spread loads.

*600 mm diameter plate is only carried as required. It requires a two-man crew due to its weight.

Our plate test site teams carry equipment suitable for testing up to 400 kN/m2 or 40 tonnes / m2 on a 450 mm diameter plate. Higher loads can be tested with additional notice.

Accuracy is essential! - Geotest always use a fully calibrated load cell to monitor pressure on the plate. This is far superior to a calibrated pressure system which can vary significantly over time.