Implementation and Use of a Measurement While Drilling System: Lessons Learned and Future Challenges-Paper

Paper

Pdf Summary

The New Hampshire Department of Transportation implemented Measurement While Drilling (MWD) in routine geotechnical investigations and evaluated it across 14 sites and approximately 40 boreholes between 2021 and 2024. MWD continuously records drilling parameters—including penetration rate, thrust, rotation, torque, vibration, and drilling-fluid pressure and flow—providing a detailed profile of ground conditions alongside conventional Standard Penetration Tests (SPT) and piezocone tests (CPTu).<br /><br />Field trials refined equipment, calibration, data-display settings, and operating procedures. A key improvement was adding a wireless instrumented drill rod to measure torque and thrust directly. These measurements were more precise than thrust estimates derived from the rig’s hydraulic pressure line. The study also found that choosing a durable carbide button bit helped reduce uncertainty from tool wear, while keeping driller-controlled variables reasonably consistent improved comparisons between depth intervals.<br /><br />Results from Durham, New Hampshire, showed that MWD profiles can identify changes in stratigraphy and distinguish softer materials from dense till, cobbles, boulders, and weathered bedrock. In these coarse deposits, SPT results may be unreliable or unavailable because of refusal, poor sample recovery, or interruptions to advance. MWD offers continuous data through such intervals, can be collected rapidly, and complements rather than replaces conventional testing. Torque-inclusive compound parameters provided more stratigraphic detail than the Somerton index, which does not use torque.<br /><br />Interpretation nevertheless depends on context. Bit type, drilling adjustments, fluid conditions, and observations of cuttings should be considered, particularly when no SPT profile is available. The authors emphasize the need for standardized procedures and stronger guidance for data reduction, as well as further research linking drilling parameters to soil and rock properties. Wider adoption also depends on equipment availability, cost, and dissemination of the technology. Overall, the campaign demonstrates that MWD can improve subsurface characterization without disrupting routine drilling, provided measurements are collected consistently and interpreted with supporting site information.

Keywords

Measurement While Drilling

MWD

geotechnical investigations

New Hampshire Department of Transportation

Standard Penetration Test

SPT

piezocone test

CPTu

stratigraphy

subsurface characterization