Anyone that uses the CPT acknowledges that when dealing with data interpretation Dr. Robertson's published research is always the basis for such a task. Since first published, the non-normalized SBT chart is used by many users to retrieve information about soil type behavior, although the successor SBTn chart (normalized SBT) is known to be more reliable.

Dr. Robertson constantly listens to CPT users so he decided to update the original 1986 chart so that it will be more directly comparable to the normalized one. The obvious advantage of the SBT chart is that it can be used real time. The chart is formed using raw CPT data, cone resistance qc and friction ratio Rf. These 2 variables do not depend on previous knowledge of soil unit weight and ground water conditions that are not available during the CPT. By post processing CPT data one may review the SBTn chart and retrieve information on how confinement pressures alter the interpreted profile.

One more time we are extremely honored that Dr. Robertson revealed to us the updated plot so that we can update the software and test its behavior. When CPeT-IT gets the final approval from Dr. Robertson we will immediately release an update so that our users may benefit from this new feature!!!

We wish you all a very Merry Christmas and a Happy New Year!!!!