Drilled Shaft Integrity Testing Comparison and Evaluation Considerations for Thermal Integrity Profiling and Cross-hole Sonic Logging-Video

Video Transcription

Video Summary

Matthew Becker of GRL Engineers presents drilled-shaft integrity testing using crosshole sonic logging (CSL) and thermal integrity profiling (TIP), focusing on two river projects. In the first, a shaft with a bidirectional cell showed severe CSL signal delays near the cell, while TIP data at peak temperature helped distinguish the engineered feature from a defect; the shaft was judged satisfactory. In the second, a fully cased shaft had highly abnormal initial CSL results, which improved substantially when testing was repeated two days later. TIP showed unusually late peak heating, demonstrating that shafts do not always peak within the typical 24–48 hours.<br /><br />The cases highlight the importance of collecting TIP data at multiple times, retesting CSL when results may be affected by concrete maturity, and using construction details and environmental boundaries to interpret anomalies. Integrity testing supports, but does not replace, the overall shaft approval process.

Keywords

drilled-shaft integrity testing

crosshole sonic logging

thermal integrity profiling

bidirectional cell

concrete maturity

shaft approval process