Dynamic Cone Penetrometer for Foundation Design 1

[mitchelon]

Have any of you, with experience working in a geotechnical testing agency, developed correlations for the soils in your area between the DCP and soil properties or between DCP and any other penetration test (i.e. SPT)? I always thought of the DCP as a method for pavement analysis/design and for verification of soil conditions during construction (which will need correlations with another method), until a geotech testing agency sent me a set of DCP tests, which were used in the design of several spread footings. He did not provide any data to support his bearing capacity calculations. They claim to have developed their own correlations for the area. He did not specify with what method was the test correlated. Just wondering what your experience with this method for foundation design has been?

 

[BigH]

Mitchelon. I suggest that you do a search of the various forums at the site; dynamic cone penetration test, correlations thereto, etc. have been extensively discussed in a number of threads - some fairly recent. You have used DCP - but haven't defined the "nature" of your DCP. As you will find in other threads, for some, it is the TRRL miniature DCP that is used for estimated CBR of roadway foundation subgrades. There is Sower's DCP explained in his book (1.5 inch dia cone I believe). I used, what is extensively used in Canada (and correlations are/were given in the Cdn Fdn Engr Manual) which is a 2 inch 60deg apex cone attached to A-rods driven with a 140 pound hammer dropping 30 inches. There are other dynamic cones also out there - many regional, many of other countries.
thread256-63347
thread256-41671
thread274-156395

 

[mitchelon]

BigH, thanks. I will check those other threads.

The DCP in question is a 1-3/8"diam rod with a 45deg cone point and a 15 lb steel ring weight falling 20" on an E-rod slided drive.