KINEMATIC SEISMIC RESPONSE AND BENDING OF FREE-HEAD PILES IN LAYERED SOIL

KAVVADAS, M; GAZETAS, G

dc.contributor.author	KAVVADAS, M	en
dc.contributor.author	GAZETAS, G	en
dc.date.accessioned	2014-03-01T01:42:06Z
dc.date.available	2014-03-01T01:42:06Z
dc.date.issued	1993	en
dc.identifier.issn	0016-8505	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/23707
dc.subject	DYNAMICS	en
dc.subject	EARTHQUAKES	en
dc.subject	NUMERICAL MODELING AND ANALYSIS	en
dc.subject	PILES	en
dc.subject	SOIL STRUCTURE INTERACTION	en
dc.subject.classification	Engineering, Geological	en
dc.subject.classification	Geosciences, Multidisciplinary	en
dc.subject.other	FOOTINGS	en
dc.title	KINEMATIC SEISMIC RESPONSE AND BENDING OF FREE-HEAD PILES IN LAYERED SOIL	en
heal.type	journalArticle	en
heal.language	English	en
heal.publicationDate	1993	en
heal.abstract	The paper studies the kinematic response of free-head piles. Such pile deformation has triggered structural damage in many strong earthquakes. In this Paper dimensionless parametric graphs for pile bending moments are presented which pertain to characteristic two-layer soil profiles. The results are derived by using an existing rigorous dynamic finite-element code, and by implementing a realistic beam-on-dynamic-Winkler-foundation formulation specifically developed for the kinematic response of piles in layered soil. The Winkler model is shown to reproduce quantitatively even detailed trends observed in the finite-element results; a simple analytical expression is thereby developed for estimating the Winkler stiffness in terms of the local soil Young's modulus and key dimensionless pile/soil parameters. The study concludes that even relatively flexible piles may not exactly experience the wavy and abruptly changing ground deformation of the free field. The critical region of pile distress due to such kinematic loading is shown to be at or near the interface between alternating soft and stiff soil layers. The magnitude of the bending moment at such critical interface locations depends mainly on the stiffness contrast of the two layers through which the pile penetrates, the excitation frequency and the relative rigidity of the pile. A constraining cap may exert an important effect on such kinematic deformations.	en
heal.publisher	THOMAS TELFORD SERVICES LTD	en
heal.journalName	GEOTECHNIQUE	en
dc.identifier.isi	ISI:A1993LJ24700002	en
dc.identifier.volume	43	en
dc.identifier.issue	2	en
dc.identifier.spage	207	en
dc.identifier.epage	222	en