Analysis and modelling of the noise generation during vibratory pile driving and determination of the optimization potential

Impact driving, pressing and vibrodriving are the tbree main methods to drive sheet piles. Vibratory pile driving is efficient when compared to impact driving: its installation time is shorter; it generates less noise, and reduces the damage to the driven sheet piles. The sound level generated during vibrodriving varies almost between the very high level of an impact driving and the lowest sound level of a pressing. This doctoral thesis, entitled „Analysis and modelling of the noise generation during vibratory pile driving and determination of the optimization potential“, was made within the Research Unit of Engineering at the University of Luxembourg and in collaboration with ArcelorMittal Research & Development Esch. In the first part, sound measurements feasibility is thoroughly studied. Particular attention is paid to the measurement conditions on construction sites and to the measurement methods (measurements of sound power level, beamforming and thermography). These methods are outlined and the provided results are compared. In addition, the different causes of noise such as impacts with the safety device, the guides, or the neighbouring sheet piles are analysed. A large part of the noise can be generated in the interlocks of the sheet piles. Various parameters influencing the expected noise level are studied in details. In the second part of the thesis, the acceleration measurements of the full-scale experiments are used to calibrate a Finite Element model. A parametrie study analyses how the most important mechanical parameters influence the noise level.