New Insights on Detecting Flaws with CSL and TIP-Video

Video Transcription

Video Summary

Andy Bachman summarizes research for Wisconsin and Missouri DOTs comparing crosshole sonic logging (CSL) and thermal integrity profiling (TIP) for drilled shafts. The methods are complementary, not interchangeable: each detects some flaws better than the other, and neither is perfect. CSL interpretation should consider both first-arrival time and signal-energy reduction. TIP interpretation should use temperature-over-time data as well as temperature-versus-depth plots; this helped identify soft-bottom conditions that earlier guidance suggested TIP might miss.<br /><br />Bachman emphasizes that integrity testing is only one part of achieving shaft quality; planning, contractor qualifications, inspection, and installation records matter. He recommends selecting tests according to project-specific risk, reviewing installation records when interpreting results, and using TIP wires rather than probe methods. Both tests may be appropriate for especially critical shafts, but routinely conducting both is not necessary.

Keywords

crosshole sonic logging

thermal integrity profiling

drilled shaft integrity

CSL interpretation

TIP data analysis

shaft quality control