000021651 001__ 21651
000021651 005__ 20170622131258.0
000021651 04107 $$aeng
000021651 046__ $$k2017-06-15
000021651 100__ $$aAuersch, Lutz
000021651 24500 $$aSTATIC AND DYNAMIC BEHAVIOUR OF PILE FOUNDATIONS IN HOMOGENEOUS AND INHOMOGENEOUS SOILS

000021651 24630 $$n6.$$pComputational Methods in Structural Dynamics and Earhquake Engineering
000021651 260__ $$bNational Technical University of Athens, 2017
000021651 506__ $$arestricted
000021651 520__ $$2eng$$aOffshore wind energy towers are dynamically loaded by waves and wind. Pile foundations provide stiffness and damping and should be properly calculated. A combined finite-element boundary-element method for the dynamic interaction of flexible structures and the soil has been developed. The flexible structures such as single piles or complete wind energy towers are modeled by the finite element method whereas the homogeneous or layered soil is modeled by the boundary element method which uses the Green’s functions for interior loads in the layered half-space to establish the dynamic stiffness matrix of the soil. Soils with a stiffness that is continuously increasing with depth can be modeled as multi-layer soils with step-wise increasing stiffness. The effects of different parameters such as the stiffness of the soil, the axial and bending stiffness of the pile, and the radius of the cylindrical contact area will be analysed for the different components of excitation (vertical, horizontal, rotation and coupling). The results can be determined as specific power laws which are different for the different load cases and for the different soil models (Winkler support, homogeneous continuum, continuum with increasing stiffness). The dynamic effect of radiation damping will be analysed by the frequency-dependent compliance functions. A clear layering of the soil can cause noticeable changes in the dynamic compliances as reductions of the stiffness and the damping in certain frequency ranges (below and around layer resonance frequencies). The distribution of the displacements along the pile help to explain the observed laws. An example of an offshore wind energy tower has been modeled and calculated for wind, wave and weight loads. The resonances of the tower are usually limited by the radiation damping which is strongest for a soft soil.

000021651 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000021651 653__ $$apile foundation, finite-element boundary-element method, pile bending stiffness, soil stiffness, continuously inhomogeneous soils, layered soils, wind energy tower.

000021651 7112_ $$aCOMPDYN 2017 - 6th International Thematic Conference$$cRhodes Island (GR)$$d2017-06-15 / 2017-06-17$$gCOMPDYN2017
000021651 720__ $$aAuersch, Lutz$$iMarkfort, Greta
000021651 8560_ $$ffischerc@itam.cas.cz
000021651 8564_ $$s1238754$$uhttps://invenio.itam.cas.cz/record/21651/files/17389.pdf$$yOriginal version of the author's contribution as presented on CD, section: [RS22] Soil-structure interaction
.
000021651 962__ $$r21500
000021651 980__ $$aPAPER