The innovative approach for this new method of quality control is based on vibration monitoring in hardened primary columns. The continuous rotation of the jet grouting rod produces a characteristic profile of vibration which can be measured in single columns and composed structures. Fast Fourier transformations (FFT) of recorded vibration signals allow to interpret the processed acceleration graphs to specify the degree and quality of overlap between primary and secondary columns as well as the diameter of single columns.
Subjects: None provided
Author: Nikolaus Schneider, General Manager / Dipl.-Ing. and Silke Appel
Publisher: DFI, EFFC