Rigid Inclusion Quality Control and Performance Verification Using Drilling Parameters: A Streamlined Approach-Paper

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The paper presents a streamlined quality-control method for rigid inclusions using data collected by Monitoring While Drilling (MWD) systems. These systems record installation parameters such as torque, downforce, rotation and penetration rates, and grout volume. Although commonly reviewed only in individual PDF logs, the data can reveal changes in ground conditions and help assess installed elements.<br /><br />The authors calculate a Penetration Resistance Index (PRI) from torque and downforce to represent average resistance at the tool–soil interface. Integrating PRI over the portion of an element below its estimated neutral plane produces an Integrated Resistance Index (IRI). Production-element IRI values can then be compared with a target derived from an instrumented load-test element. Batch processing makes it practical to analyze many elements, compare results with nearby cone penetration test (CPT) data, and display performance trends by element or location.<br /><br />Case studies show that MWD-derived resistance trends generally corresponded with CPT and load-test interpretations. Comparing production IRI values with target values helped identify elements warranting review and assess whether areas had weaker or stronger ground conditions. This information can support timely decisions about additional or deeper elements in weaker zones, and possible design optimization where conditions are more favorable.<br /><br />The authors emphasize that PRI and IRI are screening indices, not direct design parameters. Results depend on simplifying assumptions, measurement quality, and accurate estimates of the neutral plane. They recommend better torque and downforce sensors, integrated data processing, and geolocation to enable more reliable, potentially real-time assessment. Overall, systematic MWD analysis can make quality control faster and more comprehensive than manual log review, while helping project teams identify construction issues and opportunities to improve efficiency.

Keywords

Monitoring While Drilling

MWD data

rigid inclusions

quality control

penetration resistance index

PRI

integrated resistance index

IRI

cone penetration test

load test