Influence of different pile installation methods on dense sand

A current investigation subject of geotechnical modelling is the realistic representation of the installation process of offshore piles and its influences on the surrounding soil. Depending on the soil conditions piles can be installed with different installation technologies like impact driving, vibratory driving or jacking. The soil disturbances produced as a consequence of the pile installation affect the pile capacity. The dimension of the affected region depends on the installation process itself and its parameters as well as the soil initial state and the pile geometry. Currently, there are no general approaches which can predict the effects of pile installation on the soil conditions. In this contribution a brief summary of published data describing installation effects for impact driven, vibratory driven and jacked piles is given. Secondly, the influences of different pile installation methods on the surrounding soil are presented based on experimental results for non-cohesive soils from various projects. These will be analyzed by means of a comparison of dynamic probe light (DPL) and cone penetration tests (CPT) executed before and after the pile installations. Additionally the area of influence will be quantified with respect to their relative distance to the pile axis. Finally, based on these results recommendations for future works will be given.