Method of Predicting Soil Mechanical Parameters in Shallow Formation While Jetting Process in Deepwater Drilling

Since it is difficult to collect soil samples from layers deeper than 10 meters below the sea floor, the acquisition of shallow soil mechanics, based on the variation of drilling parameters in the deepwater drilling process, is not only economical but also reliable.

In this paper, we analyze the variation of subsea soil properties based on the variation of deepwater jet-drilling construction parameters, calculate the lateral friction resistance of conductor by use of WOB and displacement parameters in the jetting process, and determine the drilled formation's shear strength and internal friction angle in consideration of restored friction resistance. In order to verify the accuracy of the prediction-while-drilling model on seabed shallow soil mechanics, indoor unit and field simulation experiments were separately conducted.