TY - CONF A1 - Niederleithinger, Ernst A1 - Baeßler, Matthias A1 - Georgi, Steven A1 - Herten, M. T1 - Comparison of static and dynamic load tests on bored piles in glacial soil T2 - International conference on piling & deep foundations N2 - BAW and BAM have performed a large scale comparison and calibration test on static and dynamic load capacity evaluation of bored piles in glacial sandy soil. The test was performed using eight piles at the BAM test site for technical safety at Horstwalde 50 km south of Berlin. The test area has been prepared and investigated in great detail using boreholes, cone penetration tests, pore pressure sensors and geophysical methods to assure controlled conditions for all piles and tests. The piles (10 m length, 0.9 m diameter) are mainly friction piles (low toe resistance) and have been checked by integrity testing. Five piles have been tested by five contractors using the dynamic method in a blind experiment, the other ones piles by static load and/or later on by the dynamic method. Some piles have been equipped with additional fibre optic Instrumentation which proved to be robust and helpful in interpreting the results of static, dynamic and integrity tests. We have experienced a deviation of the dynamic load test results gathered in the blind experiment from the static values of up to 20% in most cases, sometimes even up to 30%. This can be related to the known soil inhomogeneities, interpretation and modelling in CAPWAP and method inherent uncertainties. In cases where the static values were known by the testers for calibration, the deviations were significantly smaller. It has to be taken into account, that the two static load tests showed different results as well. Due to the low toe resistance, use of a big drop weight (11 tons) and large drop heights most piles suffered from cracking, which was clearly seen in follow up integrity tests and confirmed by excavation. The piles are available for further research. T2 - International conference on piling & deep foundations CY - Stockholm, Sweden DA - 21.05.2014 KW - Piles KW - Static load test KW - Dynamic load test KW - Integrity PY - 2014 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/31202 AN - OPUS4-31202 SP - 1 EP - 8 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany