Analysis of Free-Fall Penetrometer Data

A summary of available techniques for analyzing free-fall penetrometer data is presented. The merits and drawbacks of the various analytical penetration techniques are discussed in relation to their applicability to in situ soil testing. A penetration theory based on momentum considerations is developed for a penetrometer falling freely on a C-Φ soil target. The analytical relationship can be used for calculating maximum penetration depth, velocity profile, and target strength properties. The procedures have been briefly discussed for estimating soil strength properties from the test results of a free-fall penetrometer instrumented with accelerometer, cone resistance, and sleeve friction measuring devices.