In-Situ Construction Materials Testing

At Perry Testing, we use a Dynamic Core Penetrometer (or DCP) to obtain an indicative CBR value without the need for expensive downtime such as plant and operator costs.

Generally applied to the ground via specially created trial pits or core holes, DCP testing is carried out by dropping a weight from a known distance onto the cone. The resultant movement measured can then be read directly from the instrument.

DCP testing is typically used to measure road and pavement condition and stiffness. That said, we can also use the dynamic cone penetrometer to measure the strength of in-situ soils as well as to determine both the thickness and location of underlying soil layers.

Hand shear vane testing involves the application of an instrument in order to determine the undrained shear strength of cohesive soils.

The result can be given in Kn/M² or it can be given as a vane shear strength using the calculation given in British Standard BS 1377. Either of these results can be provided instantly on site by our knowledgeable engineers.

Carried out in accordance with British Standard BS 1377, incremental plate load testing is an extremely popular method of…

• Proving pile mats
• Proving crane mats prior to the arrival of plant on site
• Proving concrete slabs prior to the arrival or design of heavy plant

Our specialist engineers will apply a counterweight (known as ‘kentledge’) to the surface with the weight being applied varying according to the loads that need to be simulated. The appropriate load will then be applied to the plate with any distortions being meticulously documented.

CBR testing (or California Bearing Ratio testing) can be used to evaluate the load-bearing potential of roads, pavements, and driveways, amongst other surfaces. It can prove particularly useful during situations involving a potential change in the use of a surface, such as the need to accommodate higher traffic volumes or heavier loads, or when gauging the quantities of materials needed for prospective road construction projects.

Experts in our field, Perry Testing offers a comprehensive sand replacement density testing service, designed to measure the in-situ density of natural soils or imported materials using sand pouring cylinders.

The in-situ density is normally used for highway or pavement design purposes, providing designers and engineers with the relevant ‘degree of compaction’ (required for highway and site specifications). This allows our clients to be confident in the compaction of the material before proceeding with final layers.

Sand replacement density testing is fully described in British Standard BS 1377: Soils for Civil Engineering Purposes: Part 9 and is both an efficient and accurate way of accessing the density of most materials.

It is worth noting that, unlike other methods, with SRD testing there is no need for time consuming and expensive calibration of equipment for every site and material type.

Core cutter density testing is used for almost the same purpose as SRD testing (covered above). This time, however, it is used solely for cohesive materials (e.g. clay). As with the former method, this is an extremely effective way of both quickly and accurately checking compaction on site.

Once collected, the samples can then be used for further tests such as triaxial or permeability assessments.

Not all testing is carried out there and then on site. Many of the tests we most commonly carry out involve a physical sample being taken on site, with that sample then being transported to one of our UKAS-accredited partner laboratories for in-depth analysis.

For more information on these services, visit our laboratory testing services page. Alternatively, why not get in touch?