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Integrated Analysis Of Turbomachinery Frame-Foundation-Soil Interaction, Madhira R. Madhav, N. G. R. Iyengar, S. Kathiroli Mar 1991

Integrated Analysis Of Turbomachinery Frame-Foundation-Soil Interaction, Madhira R. Madhav, N. G. R. Iyengar, S. Kathiroli

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

For the smooth functioning of turbomachines, the design of the rotor, the bearings, the supporting structure, and the foundation should be carried out as an integrated system. The frequency domain method in conjunction with FEM is chosen for the analysis. The modified influence matrix boundary condition method is applied to reduce the number of equations to be solved. Results for 4 idealized cases are compared. It is shown that the interaction effects are significant in the lowest frequency domain.

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Simple Design Methods For Vibration Isolation By Wave Barriers, Tahmeed M. Ai-Hussaini, Shahid Ahmad Mar 1991

Simple Design Methods For Vibration Isolation By Wave Barriers, Tahmeed M. Ai-Hussaini, Shahid Ahmad

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Rectangular wave barriers (open or infilled trenches) are frequently used in engineering practice to reduce the ground vibrations caused by propagating surface (Rayleigh) waves of relatively small wave lengths. This paper presents models involving simple algebraic formulas for the design of rectangular wave barriers in homogeneous soil deposits. Both vertical and horizontal ground vibrations are considered. An extensive parametric investigation was conducted using a direct boundary element method algorithm. Simple models based on the key dimensionless parameters that control the vibration screening effectiveness were then developed. The utility of such models is established through comparisons with rigorous numerical solutions and …

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Centrifuge Modeling For Dynamic Geotechnical Studies, R. S. Steedman Mar 1991

Centrifuge Modeling For Dynamic Geotechnical Studies, R. S. Steedman

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The field of dynamic centrifuge modelling has developed rapidly over the past decade, with international interest in both earthquake and blast modelling. The paper discusses the proliferation of facilities and the insight that can be gained from the interpretation of dynamic model test data now available using hand calculations and advanced techniques of digital signal processing.

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Piles Under Dynamic Loads, M. Novak Mar 1991

Piles Under Dynamic Loads, M. Novak

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The paper deals with some of the more recent developments in pile dynamics. It reviews the progress in the analysis of single piles and pile groups, field as well as laboratory experiments and soil-pile-structure interaction. The influence of pile-soil interface is discussed and extensive references are given.

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Seismic Amplification In The Presence Of Geological And Topographic Irregularities, E. Faccioli Mar 1991

Seismic Amplification In The Presence Of Geological And Topographic Irregularities, E. Faccioli

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Following some introductory remarks on the key aspects of seismic site effects evaluation and on new data of special interest from recent earthquakes, the first part of the paper discusses and compares the performance of numerical 2D and 1D models, as well as of simple exact solutions, in problems of local soil response and of topographic amplification. The second part is devoted to the illustration of a very promising computational tool, i.e. the Fourier (or pseudo spectral) method, for time-domain analyses of seismic wave propagation in heterogeneous elastic media.

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Earthquake Probabilities On The New Madrid Fault And The Impact Of Loma Prieta On Central U.S. Earthquake Preparedness, David Stewart Mar 1991

Earthquake Probabilities On The New Madrid Fault And The Impact Of Loma Prieta On Central U.S. Earthquake Preparedness, David Stewart

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Reliable probabilities of future damaging earthquakes in the New Madrid Fault Zone for purposes of mitigation and response planning are not available, even though considerable thought and research has gone into this question. Generalizations sufficient for pre-earthquake planning do exist, however, which suggest the need to prepare for at least a 50% chance of a 6.0 surface wave magnitude event within a decade, but that a repeat of the massive 8.0 magnitude events of 1811-12 need not be of concern for at least another century or two. The Loma Prieta was a significant stimulus toward greater earthquake planning and preparation …

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Second International Conferences On Recent Advances On In Geotechnical Earthquake Engineering And Soil Dynamics, Multiple Authors Mar 1991

Second International Conferences On Recent Advances On In Geotechnical Earthquake Engineering And Soil Dynamics, Multiple Authors

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

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Past Proceedings: Second International Conference On Recent Advances In Geotechnical Earthquake Engineering And Soil Dynamics, St. Louis (1991), Multiple Authors Mar 1991

Past Proceedings: Second International Conference On Recent Advances In Geotechnical Earthquake Engineering And Soil Dynamics, St. Louis (1991), Multiple Authors

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

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Table Of Contents, Multiple Authors Mar 1991

Table Of Contents, Multiple Authors

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

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Energy-Absorbing Ability Of Texsol, Phong M. Luong Mar 1991

Energy-Absorbing Ability Of Texsol, Phong M. Luong

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Texsol is a 30 soil-fiber composite, obtained using a technique of soil reinforcement by incorporation of continuous textile fibers. The overall mechanical properties of Texsol result therefore from those of its components: soil and fibers. An experimental approach has been carried out in order to grasp the basic aspects of the stress-strain response of Texsol subjected to monotonic, cyclic and vibratory loadings. The study confirms that the application of Texsol to earthquake resistant earthworks and traffic structures could be of great interest and particularly suitable as shown by its ductility and energy-absorbing capacities that are readily evidenced by the laboratory …

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Lateral Stiffness And Damping Coefficient Of Soils For Seismic Analysis Of Buried Pipelines, Xinjian Zhang, Leon R. L. Wang, Isao Ishibashi Mar 1991

Lateral Stiffness And Damping Coefficient Of Soils For Seismic Analysis Of Buried Pipelines, Xinjian Zhang, Leon R. L. Wang, Isao Ishibashi

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The stiffness and damping coefficient of soil are critical parameters in the Winkler's model for the seismic analysis of buried pipelines. This paper presents an analytical study in calculating the lateral dynamic stiffness (elastic and inelastic) and damping coefficient of soils for the seismic analysis of buried pipelines. The effects of the depth of the buried pipeline and the variation of Poisson's ratio of soils are cons1dered. In the analysts, first, by using the elastic half-space theory, the elastic stiffness and geometrical damping coefficient of soils are obtained. From the numerical results, the elastic stiffness and geometrical damping coefficient by …

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Session 9: Closing Remarks, Ken-Ichi Tokida Mar 1991

Session 9: Closing Remarks, Ken-Ichi Tokida

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

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A Numerical Solution Of Wave Equation For Dynamic Compaction Of Soil, K. B. Agarwal, B. Siva Ram Mar 1991

A Numerical Solution Of Wave Equation For Dynamic Compaction Of Soil, K. B. Agarwal, B. Siva Ram

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

It is a known fact that any disturbance at the ground surface, like the one created by vibratory, compactors or by application of blast pressure on detonation of a foamed propellant, is transmitted into ground until it is weak enough to travel deeper and farther. The ground acceleration at various points, induces compaction. The transmission of vibrations due to such surface dynamic loads are governed by the equation of motion based on Newton's second law. The equation of motion is presented in Euiler's Coordinates using tensor notation and is solved for surface displacements due to surface dynamic loads. These loads …

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Session 1: Discussions And Replies, Multiple Authors Mar 1991

Session 1: Discussions And Replies, Multiple Authors

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

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In Situ And Laboratory Tests For The Evaluation Of Dynamic Geotechnical Properties Of A Cohesive Deposit In Florence, T. Crespellani, G. Vannucchi, A. Ghinelli Mar 1991

In Situ And Laboratory Tests For The Evaluation Of Dynamic Geotechnical Properties Of A Cohesive Deposit In Florence, T. Crespellani, G. Vannucchi, A. Ghinelli

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

In order to determine dynamic parameters to use for seismic microzoning purposes in a new development area near Florence, the dynamic behavior of the alluvial silty clays situated in the upper 60 m of the deposit was experimentally investigated using geophysical surveys and cyclic laboratory tests. Previous studies on the geotechnical properties of the clays of Florence revealed that, in spite of some similarities in a comparison with other coeval clays described in the literature this soil exhibits a few anomalies, as e.g. higher variations between field and laboratory shear waves velocities and remarkable differences in the coefficients of the …

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Post Evaluation On Reservoir Triggered Seismicity Of Khao Laem Dam, N. Hetrakul, B. Tanittiraporn, R. Sittipod, P. Vivattananon Mar 1991

Post Evaluation On Reservoir Triggered Seismicity Of Khao Laem Dam, N. Hetrakul, B. Tanittiraporn, R. Sittipod, P. Vivattananon

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Investigation on reservoir associated earthquake phenomena in western part of Thailand was carried out since early 1983. After impoundment of Khao Laem Reservoir in June 1984 earthquake events had been recorded by micro seismic network around reservoir area. Evaluation of seismic parameters and earthquake pattern and the focal mechanism solutions indicate the earthquakes were triggered by impoundment and the hypocentral distribution confirm the earthquake activities along the north east direction. Results obtained from investigation clearly differentiate the reservoir induced earthquakes phenomena from natural tectonic earthquakes.

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General Report Session 10: Wave Propagation In Soils, Chaim J. Poram Mar 1991

General Report Session 10: Wave Propagation In Soils, Chaim J. Poram

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

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Application Of The Elastoplastic-Viscoplastic Bounding Surface Model To Cyclic Loading, Victor N. Kaliakin Mar 1991

Application Of The Elastoplastic-Viscoplastic Bounding Surface Model To Cyclic Loading, Victor N. Kaliakin

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The predictive capabilities of the elastoplastic-viscoplastic bonding surface mode, with emphasis response of cohesive soils subjected to cyclic loading, are discussed herein. This model, which represents a generalized three-dimensional constitutive formulation for isotropic cohesive soils, is developed within the framework coupled elastoplasticity-viscoplasticity and critical state soil mechanics.

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An Approach To Characterise Cyclic Deflection Of Piles In Calcareous Soil Media Under Offshore Wave Loading Conditions, Y. S. Golait Mar 1991

An Approach To Characterise Cyclic Deflection Of Piles In Calcareous Soil Media Under Offshore Wave Loading Conditions, Y. S. Golait

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Behavior of piles subjected to cyclic lateral loads due to wave action is an important aspect which needs to be evaluated for analyzing and designing these piles supporting offshore structures. The study on the model piles in calcareous soil media was therefore undertaken to investigate the cyclic pile deflection response under offshore wave loading conditions. The test results are analyzed and interpreted to evolve an approach to characterize the cyclic deflection behavior of piles under critical storm loading effect and normal wave loading action.

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General Report Session 2: Model Testing In Cyclic Loading, Mladen Vucetic Mar 1991

General Report Session 2: Model Testing In Cyclic Loading, Mladen Vucetic

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Geotechnical earthquake engineering problems and similar soil dynamics problems usually involve random three directional cyclic loads, complicated stratification of soil deposits and geometry of supported structures, heterogeneity, anisotropy, and nonlinearity of soils, large degradation of soil stiffness and strength accompanied by equally large displacements and deformations, complex interaction between different soil deposits and between the foundation soil and the supported structure, etc. On the other hand, the empirical and analytical methods used in conjunction with standard field testing or standard laboratory cyclic testing on small specimens, which are currently available in engineering practice, are relatively simple and limited to ideal …

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Influence Of Liquefaction To Pile-Soil-Structure Interaction, Tadahiko Shiomi, Michlo Sugumoto, Yoshimasa Shigeno, Yoshio Suzuki Mar 1991

Influence Of Liquefaction To Pile-Soil-Structure Interaction, Tadahiko Shiomi, Michlo Sugumoto, Yoshimasa Shigeno, Yoshio Suzuki

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Influence of liquefaction on a pile-soil-structure interaction is studied by a dynamic effective analysis code (MuDIAN). The soil properties are modeled by a Mohr-Coulomb assumption with a dilatancy model. Liquefaction takes place in shallow depth and cause the change of dynamic behavior. The approaches evaluation method of soil constants and results are reported in details.

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Displacement Based Design Of Retaining Walls, Raj Siddharthan, Prakash K. Gowda, Gary M. Norris Mar 1991

Displacement Based Design Of Retaining Walls, Raj Siddharthan, Prakash K. Gowda, Gary M. Norris

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

A relatively simple rigid plastic model to study deformation behavior of rigid retaining wall is outlined. Both sliding and tilting modes of deformation are included. The study clearly reveals that wall movement caused by tilting can be substantial. But for high values of foundation soil friction angle, the tilting component of deformation can be omitted. Since the wall movement is affected by the characteristics (strength and frequency) of the excitation history, a number of excitation histories should be considered in retaining wall designs.

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A Hybrid Model For Soil-Foundation Compliance, Chin-Hsu Lin, Teresa M. Adams Mar 1991

A Hybrid Model For Soil-Foundation Compliance, Chin-Hsu Lin, Teresa M. Adams

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

This paper describes a hybrid method that may be used to model the dynamic responses of multiple rectangular foundations resting on a homogeneous, viscoelastic stratum and excited by harmonic waves. The hybrid analysis described in this paper combines the dynamic stiffness and finite element methods. The method uses equivalent area disk loads for Green's functions at the soil surface. The dynamic stiffness method is used to obtain the stiffness matrix of the soil medium and the finite element method is used to obtain the stiffness matrix of surface foundations. The stiffness of the entire soil-structure system can be obtained using …

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A Hybrid Modeling Of Soil Structure Interaction Problems, Celso Romanel, Tribikram Kundu Mar 1991

A Hybrid Modeling Of Soil Structure Interaction Problems, Celso Romanel, Tribikram Kundu

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

A hybrid method is proposed in this research for dynamic soil-structure interaction analysis of embedded structures within a multilayered elastic half-space. A near field region, containing the structure and a portion of soil surrounding it, is modeled by finite elements while the far field formulation is obtained through the classical wave propagation theory based on the assumption that the actual scattered wave fields can be represented by a set of line sources located at a depth corresponding to the center of mass of the structure under investigation. Traction reciprocity between the two regions is satisfied exactly while displacement continuity across …

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Analysis Of Pile-Soil Dynamic Interaction By Combination Of Bem And Fem, Shiming Wu, Yuanqiang Cai, Yunmin Chen, Longzhu Chen Mar 1991

Analysis Of Pile-Soil Dynamic Interaction By Combination Of Bem And Fem, Shiming Wu, Yuanqiang Cai, Yunmin Chen, Longzhu Chen

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

A hybrid method, in which soil media is modeled by 3-D boundary elements and the pile by 1-D finite elements, for an analysis of dynamic pile-soil interaction is investigated. A new series of equations and an efficient method to deal with singularity of integrals are presented. Several effects including pile length, stiffness of the pile and surrounding soil on dynamic response are studied. Finally, the characteristics of impaired and intact piles are investigated and compared; and some case studies are presented.

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Dynamic Response Of Foundations On Two-Parameter Media, A. Alvapplllai, M. O. Faruque, M. Zaman Mar 1991

Dynamic Response Of Foundations On Two-Parameter Media, A. Alvapplllai, M. O. Faruque, M. Zaman

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

A finite element algorithm is presented to analyze the dynamic response of rectangular foundations resting on an elastic medium. The foundation is modeled by rectangular thin plate elements and the supporting elastic medium is represented by the two parameter model proposed by Vlasov. The natural frequencies of the foundation-elastic medium are investigated. A parametric study is conducted to examine the effects of the edge and corner forces, that are accounted for in the two parameter model, on the dynamic response of a plate subjected to a moving vertical force.

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Liquefaction Potential Evaluation Based On Rayleigh Wave Investigation And Its Comparison With Field Behavior, Kohji Tokimatsu, Shuji Tamura, Shinichi Kuwayama Mar 1991

Liquefaction Potential Evaluation Based On Rayleigh Wave Investigation And Its Comparison With Field Behavior, Kohji Tokimatsu, Shuji Tamura, Shinichi Kuwayama

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

A simplified method is presented for evaluating liquefaction potential of sand deposits using shear wave velocity. Effectiveness of the proposed method is evaluated through field tests at 17 sites in Niigata city where field performance during the 1964 Niigata earthquake is known. A modified version of steady state Rayleigh wave method is used in which the amplitude ratio between vertical and horizontal ground surface motions can be measured in addition to the phase velocity. Based on the measured phase velocity vs. wavelength relationship, shear wave velocity profile is determined using an inverse analysis. The liquefaction potential of each site is …

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Effective Stress Analysis Of A Sheet Pile Quaywall, Susumu Lai, Tomohiro Kameoka Mar 1991

Effective Stress Analysis Of A Sheet Pile Quaywall, Susumu Lai, Tomohiro Kameoka

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

In 1983, Nihonkai Chubu Earthquake of magnitude 7.7 hit northern part of Japan. The earthquake caused damage to quaywalls at Akita Port located about 100 km from the epicenter. The damage was associated with the liquefaction of backfill sand. In order to analyze the mechanism of the damage, soils are taken from the site for laboratory tests. The record of the earthquake motion is digitized. Based on these investigations, a two dimensional effective stress analysis is conducted. The model used in this study consists of a multiple virtual simple shear mechanisms oriented in arbitrary directions. The results of the effective …

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A Comparison And Study On Artificial Boundaries: Conceptual Aspects, Zifa Wang Mar 1991

A Comparison And Study On Artificial Boundaries: Conceptual Aspects, Zifa Wang

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The paper first analyzes the characteristics of various artificial boundaries (similarity and dissimilarity) and the derivation conditions of the boundaries. The problems involved in applying the artificial boundary in numerical computation and the solution to the problem are also discussed in the paper.

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Earthquake Damages Influenced By Soil Conditions In Historical Buildings In Istanbul, Nafiz Çamlibel Mar 1991

Earthquake Damages Influenced By Soil Conditions In Historical Buildings In Istanbul, Nafiz Çamlibel

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

This paper is based on the study of the damages by earthquakes on the historical buildings constructed in Bysantine and Ottoman period and represents a preliminary approach to the problem of identifying the causes of these damages influenced by soil conditions. In this paper, some aspects of soil conditions and foundations systems are given related to the preservation of monument, especially the presentation is concentrated on the following topics: • An estimation of seismic area and on Design basis response spectra for historical buildings. • Geotechnical problems of the old city Istanbul. • Statistical aspects of masonry of Bysantine and …

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