DCP (Dynamic Cone Penetration) Testing is a simple, reliable and cost-effective method to evaluate the in-situ stiffness profile of soil to a depth of about three feet. Its extreme portability, minimal disturbance of the subgrade, and ability to produce a continuous depth profile make it an ideal system for testing the mechanical properties of a pavement system during any stage of construction.
The following simple equation is traditionally used to express the stiffness of a material from DCP test values:
PR = Depth of Penetration / Number of Blows
If you are new to DCP testing, you may be wondering whether the PR value can be used to calculate to other, more familiar geotechnical parameters, and whether DCP test results correlate well with those from other testing systems. Much has been researched and written on this subject, and the short answer is yes—DCP testing can easily and repeatably measure the same parameters as other in-situ and lab-based soil testing methods.
For example, the California Bearing Ratio (CBR) test is another penetration test commonly used to measure the load bearing capacity of road beds. Perhaps you want to know the CBR values for a test site, but you have opted for a DCP system instead, due to its simplicity and lower cost. No problem! PR values can be converted to CBR values by applying a simple equation. This widely used conversion was developed by the U.S. Army Corps of Engineers and is used by many state DOTs and federal agencies:
Log (CBR) = 2.465 - 1.12 Log (PR)
This calculation and many others can be performed automatically by a state-of-the-art DCP setup. The Vertek SmartDCP kit can be operated and transported by a single user by hand, and provides instantaneous data collection and graphing capabilities via smartphone app. Data can be plotted in the field or emailed to your computer for further analysis. We also offer fully automated, trailer-mounted DCP systems with built-in drilling capability: these are ideal for testing subgrades beneath pavement and concrete.
In short, DCP is a highly versatile testing tool that can be scaled and customized for your application, allowing you to achieve the same functionality as other testing systems for a fraction of cost and labor. To learn more about DCP and the other geotechnical services we offer, check out our website and our catalog.