Print Email Facebook Twitter The Parallel Seismic detection of defects in pile foundations Title The Parallel Seismic detection of defects in pile foundations Author De Groot, P.H. Contributor Holscher, P. (mentor) Hopman, V. (mentor) Everts, H.J. (mentor) Van Tol, A.F. (mentor) Faculty Civil Engineering and Geosciences Department Geoscience & Engineering Programme Geo-Engineering Date 2014-10-16 Abstract The Parallel Seismic (PS) test is a non-destructive test that is used to determine the depth of foundations. This thesis explores the use of the PS method to detect flaws in in-situ constructed foundation piles as an alternative to existing testing methods. An acoustic signal is introduced to the head of the pile with a hammer. An elastic wave propagates through the pile, and vibrations are radiated out into the soil. Neighbouring the pile, geophones are lowered or pushed into the ground such that the vibrations in the soil can be measured. Theoretically, the vibrations originating from the pile shaft should provide a blueprint of the pile's condition. Flaws will affect wave arrivals, damping, and cause reflections. However, difficulties arise if the soil should be considered heterogeneous or when vibrations of the shaft are masked by other vibrations originating from the surface or the pile toe. A computer model was made using an analytical approach to determine what vibrations may develop. This was followed by two field tests with the PS on an experimental pile field. From the results an understanding of vibrations in the pile and soil was developed and an attempt was made to detect any flaws. The procedure did not sufficiently measure the vibrations radiated from the pile shaft while avoiding interference from other vibration sources or soil heterogeneity. The field test did however provide a better understanding of the vibrations that develop in the soil. This provided improvements on the model, allowing for more extensive simulations. Based on these, possible improvements on the PS procedure were realised. Subject defectsParallel seismicdetectionacoustics To reference this document use: http://resolver.tudelft.nl/uuid:166db64f-7fee-4779-af44-efbe069397af Part of collection Student theses Document type master thesis Rights (c) 2014 De Groot, P.H. Files PDF TheParallelSeismic_PHdeGroot.pdf 11.35 MB Close viewer /islandora/object/uuid:166db64f-7fee-4779-af44-efbe069397af/datastream/OBJ/view