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Dynamic interaction factors for floating pile groups
194A initial and boundary conditions. Several simulations with different assumed permeabilities are illustrated. Interpretation of results and limitations of the model are discussed.
Influence of dynamic loads 923428 Impedance functions for three-dimeasional foundations supported on an infinitely-long canyon of uniform cross-section in a homogeneous half-space Zhang, L; Chopra, A K Eart&! Eagng Struct Dyaam V20, N i l , Nov 1991, P10111027 Many techniques have been applied to analysis of surface or embedded foundations on half spaces, but the case of an infinitely long canyon of arbitrary uniform cross section cut in a homogeneous viscoelastic half space has not been successfully tackled. This system is here analysed to determine the impedance matrix of an arch dam foundation/rock interface using a direct boundary element method and full-space Green's functions. The assumption of the homogeneous half space is reasonable for sites where similar rock is present to considerable depth. 923429 Dynamic reSlXmSeof surface foondatlom on layered media Swaddiwudhipong, S; Chow, Y K; Tan, S C; Phoon, K F Eart&i F ~ a g Stract D y u m V20, N i l , Nov 1991, P10651081 A finite layer analysis is presented for steady state dynamic response of flexible or rigid massless foundations with complex geometries on layered media. Horizontal, vertical, and rocking modes of vibration are considered. Effects of size of domain, number of harmonic terms, and soil media damping on accuracy and convergence are examined. Results are compared to those obtained using other mathematical techniques. 92343O Vibration of surface foundations of arbitrary shapes Liou, G S Eart&1 F ~ n g Struct D y u m V20, NI2, Dec 1991, Pl1151125 A procedure for generating impedance matrices for foundations of arbitrary shape resting on an elastic half space medium is presented. The contact region is subdivided and contact stresses are assumed constant in each region and are expressed in rectangular coordinates. Piecewise contact tractions on the half space are then transformed into cylindrical coordinates and written in terms of an infinite series of Fourier components. Finite element modelling of the foundation structure is employed. A simple example of the method is illustrated and possible extensions discussed. 923431 Vibration of three-dimenslonal rigid raft foundation on viscoelastic medium Zhao, C; Valliappan, S Eart&! ~ St~ct Dysmm V20, NI2, Dec 1991, P11591177 A method to calculate the compliance matrix of a rigid raft foundation on a viscoelastic medium is presented which uses the finite and infinite element coupled model. This allows near field and far field modelling respectively, plus simultaneous inclusion of radiation damping and material damping. Effects of different proportions of radiation and material damping can be investigated.
923432 Analytical ~ of ¢arthqanke-indnced psrnument defommtlom Stamatopoulos, C A; Bouckovalas, G; Whitman, R V J Geoteck E q a g Di~ ASCE Vl17, NIO, Oct 1991, P14711491 A development of the Residual Strain Method, formulated in connection with cyclic wave loading of offshore foundations in sand, is presented for prediction of permanent deformations of foundations resting on sand and subject to earthquake excitation. The concepts of the original model are outlined and improvements described. The validity of the proposed constitutive model is checked against cyclic triaxial, oedometer, and torsion tests in the laboratory. The overall accuracy of the method is demonstrated by comparing its predictions to experimental measurements and field observations.
923433 Analysis of seismic settlements and pore pressures in centrifuge tests Bouckovalas, G; Stamatopoulos, C A; Whitman, R V Y Geoteeh Eagag Di~ ASCE V117, NIO, Oct 1991, P14921508 The improved Residual Strain Method, described in a companion paper (ibid,Vll7, P1471-1491), is evaluated through comparison with results of centrifuge tests simulating the response of a tank foundation resting on saturated sand and subject to earthquake type loading. Analyses with different values of permeability of soil are carried out and results used to back calculate in situ permeability and demonstrate the effects of partial drainage. Results indicate partial drainage will occur even under high frequency dynamic Ioadings, with significant effect on settlement and excess pore pressures.
923434 Dynamic interaction factors for floating pile groups Gazetas, G; Fan, K; Kaynia, A; Kausel, E J Geoteeh Engag Div A$CE V117, NIO, Oct 1991, P15311548 The superposition procedure gives an excellent approximation for dynamic assessment of pile groups, provided dynamic interaction factors are used for each frequency of interest. To assist this, a comprehensive set of dynamic interaction factor versus frequency graphs is presented for horizontal, vertical, and rocking motions at the head of each pile. These have been developed using a rigorous analytical-numerical formulation for two idealised soil profiles and three pile spacings. A wide range of values of pile/soil stiffness ratios and pile slenderness has been assigned.
923435 Sha~ ~ asmly~ of malMnd~ment ~ y o n - w a l l configuration. Technical note Prato, C A; Matheu, E E J Geoteek F,ag~g DiB ASCE VII7, N i l , Nov 1991, P18021808 An expansion of the numerical integration procedure of Prato and Dehnastro (1987) to account for the influence of valley wall shape on response of embankment dams to horizontal seismic excitation is presented. It is illustrated applied to the Long Valley Dam, and results are compared to those from 3D finite element analysis and field measurements.
© 1992 Pergamon Press Ltd. Reproduction not permitted
Influence of dynamic loads 923428 Impedance functions for three-dimeasional foundations supported on an infinitely-long canyon of uniform cross-section in a homogeneous half-space Zhang, L; Chopra, A K Eart&! Eagng Struct Dyaam V20, N i l , Nov 1991, P10111027 Many techniques have been applied to analysis of surface or embedded foundations on half spaces, but the case of an infinitely long canyon of arbitrary uniform cross section cut in a homogeneous viscoelastic half space has not been successfully tackled. This system is here analysed to determine the impedance matrix of an arch dam foundation/rock interface using a direct boundary element method and full-space Green's functions. The assumption of the homogeneous half space is reasonable for sites where similar rock is present to considerable depth. 923429 Dynamic reSlXmSeof surface foondatlom on layered media Swaddiwudhipong, S; Chow, Y K; Tan, S C; Phoon, K F Eart&i F ~ a g Stract D y u m V20, N i l , Nov 1991, P10651081 A finite layer analysis is presented for steady state dynamic response of flexible or rigid massless foundations with complex geometries on layered media. Horizontal, vertical, and rocking modes of vibration are considered. Effects of size of domain, number of harmonic terms, and soil media damping on accuracy and convergence are examined. Results are compared to those obtained using other mathematical techniques. 92343O Vibration of surface foundations of arbitrary shapes Liou, G S Eart&1 F ~ n g Struct D y u m V20, NI2, Dec 1991, Pl1151125 A procedure for generating impedance matrices for foundations of arbitrary shape resting on an elastic half space medium is presented. The contact region is subdivided and contact stresses are assumed constant in each region and are expressed in rectangular coordinates. Piecewise contact tractions on the half space are then transformed into cylindrical coordinates and written in terms of an infinite series of Fourier components. Finite element modelling of the foundation structure is employed. A simple example of the method is illustrated and possible extensions discussed. 923431 Vibration of three-dimenslonal rigid raft foundation on viscoelastic medium Zhao, C; Valliappan, S Eart&! ~ St~ct Dysmm V20, NI2, Dec 1991, P11591177 A method to calculate the compliance matrix of a rigid raft foundation on a viscoelastic medium is presented which uses the finite and infinite element coupled model. This allows near field and far field modelling respectively, plus simultaneous inclusion of radiation damping and material damping. Effects of different proportions of radiation and material damping can be investigated.
923432 Analytical ~ of ¢arthqanke-indnced psrnument defommtlom Stamatopoulos, C A; Bouckovalas, G; Whitman, R V J Geoteck E q a g Di~ ASCE Vl17, NIO, Oct 1991, P14711491 A development of the Residual Strain Method, formulated in connection with cyclic wave loading of offshore foundations in sand, is presented for prediction of permanent deformations of foundations resting on sand and subject to earthquake excitation. The concepts of the original model are outlined and improvements described. The validity of the proposed constitutive model is checked against cyclic triaxial, oedometer, and torsion tests in the laboratory. The overall accuracy of the method is demonstrated by comparing its predictions to experimental measurements and field observations.
923433 Analysis of seismic settlements and pore pressures in centrifuge tests Bouckovalas, G; Stamatopoulos, C A; Whitman, R V Y Geoteeh Eagag Di~ ASCE V117, NIO, Oct 1991, P14921508 The improved Residual Strain Method, described in a companion paper (ibid,Vll7, P1471-1491), is evaluated through comparison with results of centrifuge tests simulating the response of a tank foundation resting on saturated sand and subject to earthquake type loading. Analyses with different values of permeability of soil are carried out and results used to back calculate in situ permeability and demonstrate the effects of partial drainage. Results indicate partial drainage will occur even under high frequency dynamic Ioadings, with significant effect on settlement and excess pore pressures.
923434 Dynamic interaction factors for floating pile groups Gazetas, G; Fan, K; Kaynia, A; Kausel, E J Geoteeh Engag Div A$CE V117, NIO, Oct 1991, P15311548 The superposition procedure gives an excellent approximation for dynamic assessment of pile groups, provided dynamic interaction factors are used for each frequency of interest. To assist this, a comprehensive set of dynamic interaction factor versus frequency graphs is presented for horizontal, vertical, and rocking motions at the head of each pile. These have been developed using a rigorous analytical-numerical formulation for two idealised soil profiles and three pile spacings. A wide range of values of pile/soil stiffness ratios and pile slenderness has been assigned.
923435 Sha~ ~ asmly~ of malMnd~ment ~ y o n - w a l l configuration. Technical note Prato, C A; Matheu, E E J Geoteek F,ag~g DiB ASCE VII7, N i l , Nov 1991, P18021808 An expansion of the numerical integration procedure of Prato and Dehnastro (1987) to account for the influence of valley wall shape on response of embankment dams to horizontal seismic excitation is presented. It is illustrated applied to the Long Valley Dam, and results are compared to those from 3D finite element analysis and field measurements.
© 1992 Pergamon Press Ltd. Reproduction not permitted