The ball penetrometer test is used for the assessment of undrained shear strength in very soft clays. A cyclic test can be conducted to assess the residual undrained shear strength by repeatedly moving the ball up and down over a defined test depth. The typical result from a cyclic ball penetrometer test is shown below.

 

J001_BPT 12 cyclic tests at 7.0m-9.75m and 14.jpg