DISPLACEMENT PHASE DIFFERENCES IN A HARMONICALLY OSCILLATING PILE

MAKRIS, N; GAZETAS, G

dc.contributor.author	MAKRIS, N	en
dc.contributor.author	GAZETAS, G	en
dc.date.accessioned	2014-03-01T01:09:22Z
dc.date.available	2014-03-01T01:09:22Z
dc.date.issued	1993	en
dc.identifier.issn	0016-8505	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/10932
dc.subject	DEFORMATION	en
dc.subject	DYNAMICS	en
dc.subject	PILES	en
dc.subject	VIBRATION	en
dc.subject	WAVES	en
dc.subject.classification	Engineering, Geological	en
dc.subject.classification	Geosciences, Multidisciplinary	en
dc.subject.other	DEFORMATION	en
dc.subject.other	STIFFNESS	en
dc.subject.other	VIBRATION	en
dc.title	DISPLACEMENT PHASE DIFFERENCES IN A HARMONICALLY OSCILLATING PILE	en
heal.type	journalArticle	en
heal.identifier.primary	10.1680/geot.1993.43.1.135	en
heal.identifier.secondary	http://dx.doi.org/10.1680/geot.1993.43.1.135	en
heal.language	English	en
heal.publicationDate	1993	en
heal.abstract	Analytical solutions are developed for harmonic wave propagation in an axially or laterally oscillating pile embedded in homogeneous soil and excited at the top. Pile-soil interaction is realistically represented through a dynamic Winkler model, the springs and dashpots of which are given values based on results of finite element analyses with the soil treated as a linear hysteretic continuum. Closed form expressions are derived for the phase velocities of the generated waves; these are compared with characteristic phase. velocities in rods and beams subjected to compression-extension (axial) and flexural (lateral) vibrations. The role of radiation and material damping is elucidated; it is shown that the presence of such damping radically changes the nature of wave propagation, especially in lateral oscillations where an upward propagating (reflected) wave is generated even in a semi-infinite head-loaded pile. Solutions are then developed for the phase differences between pile displacements at various depths. For most piles such differences are not significant and waves emanate nearly simultaneously from the periphery of an oscillating pile. This conclusion is useful in analysing dynamic pile to pile interaction, the consequences of which are shown in this Paper.	en
heal.publisher	THOMAS TELFORD SERVICES LTD	en
heal.journalName	GEOTECHNIQUE	en
dc.identifier.doi	10.1680/geot.1993.43.1.135	en
dc.identifier.isi	ISI:A1993KR72700009	en
dc.identifier.volume	43	en
dc.identifier.issue	1	en
dc.identifier.spage	135	en
dc.identifier.epage	150	en