How Does A Plate Load Test Work?

Plate bearing tests are normally carried out at foundation level, either on the surface or in a shallow pit. Plates of varying sizes up to 600mm diameter are available.

A counterweight or kentledge often in the form of a mechanical excavator is used to apply an increasing load upon a specified diameter circular plate to induce settlement. The vertical deformation is recorded by settlement gauges.  The test load is increased gradually until the plate starts to settle at a rapid rate.

The total value of load on the plate divided by the area of the steel plate gives the value of the ultimate bearing capacity of soil. A factor of safety is applied to give the safe bearing capacity of soil. Ultimate bearing strength of the soil may be determined from plate load test data. It is also possible to calculate an equivalent CBR value by using the modulus of sub grade reaction. The plate bearing test is normally carried out at foundation level. This can be either on the surface or in a shallow pit.

How Can EMS Geotech Help?

EMS Geotech’s experienced engineers provide Plate Load testing in accordance with BS 1377-9:1990. Our engineers will advise on the plate diameter required to match the anticipated design load and reaction load required (i.e. size of excavator) to be made available for us on site.

EMS Geotech will typically complete 10-15 tests in a day subject to site conditions and can provide you with the results the following day. Please contact us to discuss your site investigation requirements or book at test.