CBR Testing 

In-Situ and Laboratory CBR Testing throughout London and the rest of the UK.

As part of our comprehensive range of site testing services, IBEX Consulting Engineers (CE) Limited undertake professional in-situ and laboratory CBR testing in London as well as across the UK. To precisely evaluate the subgrade ground strength for your construction project, it is essential to work with our highly experienced chartered engineers who offer fast and accurate results.

IBEX CE work in partnership with a specialist UKAS accredited laboratory and complete in-situ CBR tests following BS1377 regulations. We are committed to guaranteeing a high quality of work across all projects. With over 18 years of experience in the industry, we are equipped with specialist expertise and premium equipment to provide accurate and reliable results.

Feel free to contact our team today, we’d love to get to know the details of your project. We can offer further information regarding CBR Testing London or provide a free quotation for your specifications.

About CBR Testing


The California Bearing Ratio test is an empirical measurement of the strength of subgrade materials within the ground. The CBR test can be completed independently or as part of a comprehensive geotechnical site inspection. The results provide an indicative insight into the strength and durability of the soil or rock that will lay beneath a proposed construction project.


CBR testing

Developed by the California Department of Highways, the test is used globally to determine the thickness of materials that should be implemented in the construction of roads and pavements. Using a thoroughly tested and standardised method of measurement, CBR tests determine the strength of materials underneath the surface of the ground. This offers invaluable information to account for the predicted traffic levels and typical ground movement for the planning and construction of roads, pavements or foundations.

It is worth noting that CBR tests are only conducted on particle measurements of up to 20mm. Any material larger than 20mm requires a plate load bearing test. Whilst many consider these tests to be very similar, and even use the terms interchangeably, there are some clear differences in the testing procedure and results that they provide. To learn more, check out our article on the differences between CBR and plate bearing tests 

In-situ CBR test


IBEX CE are able to attend sites across London and the UK to perform in-situ CBR testing. The test is performed by penetrating a plunger into the sample section of the ground at a consistent rate. A measurement of the pressure required to complete this action is taken. The figure is divided by the same measurement of pressure required to penetrate a standard sample of crushed rock material. The calculation will reveal CBR level for that sample. The higher the CBR reading, the harder the ground is calculated to be. Typical construction projects often require an optimal CBR result of around 80-100%.


Laboratory CBR testing


We are also equipped to perform laboratory CBR testing in London from samples across the country. Whilst the procedure is similar to in-situ testing, there is also some additional preparation during the procedure. The collected material is loosened before adding moisture. This mixture is then compacted into a cylindrical mould before following a similar procedure of using a plunger to penetrate the sample at a consistent rate. Again, the results are divided by the pressure required to penetrate the standardised crushed rock to provide the CBR result. Working in collaboration with advanced laboratory technicians allows us expedite accurate results.

Nationwide CBR testing

If you are searching for geotechnical engineers with proficient expertise in the completion of CBR tests and various ground investigation services, look no further than IBEX CE Ltd. We’ll implement high-quality testing equipment and expertise to guarantee fast and accurate readings for your use.

We are consistently dedicated to supplying cost-effective CBR testing for all of our clients. From our head office in Surrey, we offer laboratory testing and in-situ CBR tests within the City of London and throughout the Greater London boroughs, as well as across the rest of the UK.

If you require laboratory or in-situ CBR testing in London and across the UK, or any other geotechnical services, contact IBEX CE Ltd today for a no-obligation quote.

Contact Us

'Geotechnical and Environmental Specialists'

Abbey House, 25 Clarendon Road, Redhill, Surrey, RH1 1QZ

01737 452622 (ext.2622)