TY - CONF A1 - Ertel, Jens-Peter A1 - Niederleithinger, Ernst A1 - Grohmann, Maria T1 - Old ideas to improve pile integrity testing revisited and optimized T2 - NDT-CE 2015 - International symposium non-destructive testing in civil engineering (Proceedings) N2 - Low strain pile integrity testing is an established method in QA of foundation piles. The technique is very effective and well accepted for larger flaws and length determination. It is part of standards and recommendations. Challenges exist for more complicated structures (e. g. pile walls, diaphragm walls, and pile under structures) and small flaws. Interpretation is subjective in many cases. Possible solutions, e.g. the use of vibrators instead of a hammer or application of several sensors instead of one have been proposed decades ago, but not used much in practice. In several projects we are working on the extension and optimizations of these ideas, based on input from other engineering disciplines. In the frame of the project PileInspect we are working with an international consortium on the use of vibrators instead of a hand held hammer. This allows the full control of input signals as well as the use of (semi)automatic classification routines from machine diagnosis. At BAM we are using a low cost vibrator and deconvolution routines to improve the results of classical low strain testing. In another project we are working on multichannel measurements with sensor placement along the pile axis. This can be used to determine the travel direction of certain waves (downwards or upwards) to improve the interpretation of measurements on piles below constructions or pile walls. The use of ideas adapted from geophysics („vertical seismic profiling“) are helpful. Both concepts are proven by simulations results and first field tests. T2 - NDT-CE 2015 - International symposium non-destructive testing in civil engineering CY - Berlin, Germany DA - 15.09.2015 KW - Pile inspect KW - Ultraseismic KW - Low strain pile integrity testing KW - Piles KW - Shaker KW - Deconvolution KW - Vertical seismic profiling PY - 2015 SN - 1435-4934 SP - 1 EP - 4 AN - OPUS4-34716 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -