Precision of CSLT Measurement System for Defect Detection in Bored Piles

Crosshole Sonic Logging Tomography (CSLT) is an emerging innovative measurement system which provides information on the size, shape, and orientation of defects in a bored pile. In this paper, we quantify measurement precision of the CSTL system by a gage repeatability and reproducibility (R&R) study, in order to understand and model the effects of the test operators, defects, and the test machines on measurement error. We do this by setting up a test pile with three know defects and performing various measurement experiments. We use a feature extraction method to quantify measurement error. Overall, we find that the CSLT has satisfactory repeatability and reproducibility for practical usage of defect detection.