Improving Investigations with Drill Parameter Recorder Technology

Enhancing geologic and geotechnical investigation techniques is fundamental for improving the reliability of any geotechnical investigation. During a typical geotechnical drilling program, the geologist and driller work together to capture both “real” data (core logs detailing lithology, rock quality designation, samples, etc.) and “fugitive” data (driller’s notes about rig behavior or subtle subsurface variations, etc.). The fugitive data can often be as valuable to the final design and construction as the core logs or rock/soil samples. Drill parameter recorders (DPR) can be installed on drill rigs to allow for real-time monitoring-while-drilling (MWD) of important fugitive parameters, such as: penetration rate, hold-back force, torque, thrust, rotational speed, mud or water flow rates and pressures, with depth, and time. The parameters can be used to spatially correlate strata between borings, and identify areas of highly fractured rock, voids, clay seams, or weak/thin stratigraphic zones that may be washed-out or lost during drilling. Correlations also exist to specific energy, rock mass and soil strengths, and components of the rock mass rating (RMR) system. This paper provides background about DPR system and seeks to illustrate its potential uses for subsurface investigations.