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Use Of Rayleigh Modes In Interpretation Of Sasw Test, N. Gucunski, R. D. Woods Mar 1991

Use Of Rayleigh Modes In Interpretation Of Sasw Test, N. Gucunski, R. D. Woods

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

The Spectral-Analysis-of-Surface-Waves (SASW) method is a seismic method for measuring in situ elastic moduli of layered systems, like soils or pavements. The inversion process associated with SASW can be an ambiguous task in certain cases, because a field dispersion curve needs to be matched with an unknown path through a family of theoretically defined curves for an assumed profile. A study of the influence of soil stratification on participation of higher Rayleigh modes in surface wave propagation included the evaluation of theoretical dispersion curves, modal shapes and rates of energy transmission in the horizontal direction. Wave propagation due to oscillations …

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A Study Of Blast Pressure From Underwater Borehole Blasting, T. S. Thandavamoorthy Mar 1991

A Study Of Blast Pressure From Underwater Borehole Blasting, T. S. Thandavamoorthy

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

The paper presents an experimental study conducted under laboratory conditions on the measurement of the pressure waves transmitted into water that are radiated from following the detonation of an explosive charge buried in a block. In order to simulate full scale blasting operations at sea, small explosive charge of 1.8g PETN was buried in a concrete block and detonated under water. Information concerning the test set-up, instrumentation, type of explosives used, scaling factor and measurement of pressure is briefly described. The paper also presents analysis of the test results in the form of FFT’s and Transfer functions and details of …

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Control Of Seismic Response Of Structures, Chris P. Pantelides Mar 1991

Control Of Seismic Response Of Structures, Chris P. Pantelides

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

Safety requirements for structures built in seismic regions have led to techniques for absorbing the energy induced to these structures by earthquakes. Passive isolation systems such as base isolators are suitable for low-rise structures but they provide only a partial solution to the problem. This paper presents three active control techniques for reducing the dynamic response of machine supporting foundations. The concept of active control is discussed and various control strategies are presented. The active tendon system (ATS), active mass damper (AMD), and active base control (ABC) mechanisms are examined. Both optimal and non-optimal control algorithms are described and numerical …

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Current Trends In Design And Analysis Of Paper Machine Foundations, Alex Sy, W. E. Mckevitt Mar 1991

Current Trends In Design And Analysis Of Paper Machine Foundations, Alex Sy, W. E. Mckevitt

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

Current trends in the design and dynamic analysis of paper machine foundations to ensure satisfactory performance are presented in this paper. Space frame foundations for modern high speed paper machines are governed by the requirements to meet stringent alignment/deflection tolerances and dynamic stiffness requirements specified by the machine manufacturer. The current design approach considers the complete machine-foundation-soil interaction. The dynamic response analysis is commonly conducted using a suitable finite element computer code in which the soil is modelled by equivalent springs. Damping is also included in the response calculation. Appropriate stiffness and damping parameters to model the foundation soil or …

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Damage Criteria For Small Amplitude Ground Vibrations, K. Rainer Massarsch, Bengt B. Broms Mar 1991

Damage Criteria For Small Amplitude Ground Vibrations, K. Rainer Massarsch, Bengt B. Broms

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

European codes and recommendations have been reviewed with respect to critical vibration levels, causing damage to buildings. It was found that the variation of the vibration threshold levels was large between the different codes. A rational approach to assess the damage caused by ground vibrations is proposed, based on wave propagation theory. The wave length appears to be the most important parameter. The damage potential was found to be greatest when the length of the propagating wave is equal to or shorter than the length of the building. The wave length can be determined from the frequency and wave propagation …

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Session 11: Discussions And Replies, Multiple Authors Mar 1991

Session 11: Discussions And Replies, Multiple Authors

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

No abstract provided.

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Dynamic Characteristics Of Crusher Supporting Structures, P. Srinivasulu, B. Sivarama Sarma, N. Lakshmanan Mar 1991

Dynamic Characteristics Of Crusher Supporting Structures, P. Srinivasulu, B. Sivarama Sarma, N. Lakshmanan

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

Ring granulator type crushers are installed in many coal handling plants over framed type supporting structures either in steel or reinforced concrete. The causes of excessive vibrations commonly reported from these installations are discussed. The paper describes, in particular, the nature and magnitudes of exciting forces to be considered for the safe design of supporting structures for such machinery. Two practical examples are illustrated - one involving an elevated steel structure and another reinforced concrete framed structure, the latter supporting multiple crushers on the same floor. Pertinent conclusions are drawn for the benefit of future designers of such installations.

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Dynamic Characteristics Of Soils In Calculation Of Vibrations Of Foundations For Machines With Periodical, Pulse And Random Loads, Vadim M. Platesky Mar 1991

Dynamic Characteristics Of Soils In Calculation Of Vibrations Of Foundations For Machines With Periodical, Pulse And Random Loads, Vadim M. Platesky

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

The paper deals with the results of the exper1mental studies performed by the author on the foundations 0.5, 2.4 and 25 sq. m in area under periodical, Pulse and random dynamic loads. Some formulas are given to determine dynamic characteristics of soils. Methods and devices for field dynamic tests of soils are described. The results of the proposed relationship check are given.

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Ground Vibration Isolation Using Gas Cushions, K. Rainer Massarsch Mar 1991

Ground Vibration Isolation Using Gas Cushions, K. Rainer Massarsch

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

A new ground vibration isolation method is described, which uses inflated, flexible cushions. The isolation cushions have therefore a low impedance and act as vibration reflectors in the ground. Practical aspects, such as the production of the gas cushions screen, the installation method and the gas-tightness of the gas cushions are discussed. The screen can be installed to great depth, using the well-proven slurry trench technique. After installation, the trench is filled with a self-hardening cement-bentonite grout, which creates a plastic, water-tight protection layer around the cushions and assures the long term stability of the screen. The gas cushion screen …

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On Predictions And Performance Of Machine Foundations, George M. S. Manyando, Shamsher Prakash Mar 1991

On Predictions And Performance Of Machine Foundations, George M. S. Manyando, Shamsher Prakash

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

A model for predicting the amplitude versus frequency response for surface footings under vibrations is presented. The model considers the effects of soil nonlinearity and confining pressures on soil modulus and has been verified by comparing model predictions with performance field tests. The elastic half space analog solutions have been used to develop a computer program for this prediction model (Manyando, 1990). Soil nonlinearity has been accounted for by incorporating an iterative procedure in the computer program. The computer program was used to predict the footing response in vertical, torsional and coupled rocking and sliding vibrations. Predicted resonant amplitudes, resonant …

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Pile Driving Analysis: Two-Phase Finite Element Approach, P. Hölscher Mar 1991

Pile Driving Analysis: Two-Phase Finite Element Approach, P. Hölscher

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

The pile-driving process is analysed using the dynamic finite element program SATURN. The soil is modelled as a two-phase (skeleton and water) axi-symmetric continuum. The elasto-plastic behaviour of the skeleton is considered. Energy dissipation due to radiation, plastic deformation and water-skeleton friction is taken into account. The importance of permeability of the soil, its strength and its dilatancy are outlined. The soil resistance under the toe is strongly influenced by the low compressibility of the water. The results of the simulations show that the non-linear soil behaviour around the pile toe cannot be simulated satisfactorily using a single phase material. …

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Predicting Vibrations Of Soil And Buildings Excited By Machine Foundations Under Dynamic Loads, Mark Svinkin Mar 1991

Predicting Vibrations Of Soil And Buildings Excited By Machine Foundations Under Dynamic Loads, Mark Svinkin

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

This paper presents a new method that predicts the vibrational effects on existing soil, building and equipment from a designed machine foundation when it will be installed at a specific site. The method requires development of certain experimental data at an industrial site and subsequent computerized data reduction. The results are complete vibro-records at the locations of interest. The basic prerequisite of the suggested method is an experimental determining of impulse responses of soil and structures. The use of this response gives to an engineer a chance to consider heterogeneity and multiformity of soil properties. The accepted assumptions have been …

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The Optimization Principles Of The System "Mass Blast-Protected Structure", Yugeni Borisov, Boris Pishkin Mar 1991

The Optimization Principles Of The System "Mass Blast-Protected Structure", Yugeni Borisov, Boris Pishkin

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

The real work is ideological result of the investigations, which have been carried out for 25 years, on structural dynamics under the seismo-explosive loads, induced by industrial and experimental blasts, simulating natural earthquakes, and on the optimization parameters of drill explosive works in the mining quarrels.

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Torsional Dynamic Response Of Embedded Footings, Peiji Yu, E. B. Wylle, F. E. Richart Jr. Mar 1991

Torsional Dynamic Response Of Embedded Footings, Peiji Yu, E. B. Wylle, F. E. Richart Jr.

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

A computer program, originally prepared to evaluate stresses and displacements below an axisymmetric surface footing subjected to torsional loadings, has been modified to accommodate embedded footings. The material surrounding the footing can be considered as elastic, nonlinear inelastic or nonlinear inelastic including slip. Layered systems can also be treated. Good agreement was obtained in comparisons with published solutions for elastic systems, as obtained by the finite element method, and by an approximate method. In particular, comparisons were made for variations at maximum amplitude of rotation and dimensionless frequency at maximum amplitude of rotation as functions of the embedment ratio. The …

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Dedication To Harry B. Seed, Shamsher Prakash Mar 1991

Dedication To Harry B. Seed, Shamsher Prakash

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

No abstract provided.

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Earthquake Ground Motions At Soft Soil Sites, I. M. Idriss Mar 1991

Earthquake Ground Motions At Soft Soil Sites, I. M. Idriss

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

No abstract provided.

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Earthquake Potential Along The Hayward Fault, California, Glenn Borchardt, J. David Rogers Mar 1991

Earthquake Potential Along The Hayward Fault, California, Glenn Borchardt, J. David Rogers

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

The Loma Prieta event probably marks a renewed period of major seismic activity in the San Francisco Bay Area. Particularly ominous is the historic record of major events a few years apart on opposite sides of the Bay in 1836 (N. Hayward fault) and 1838 (N. Peninsula, San Andreas fault) and 1865 (Loma Prieta segment, San Andreas fault), and 1868 (S. Hayward fault) (Figure 1). Recent preliminary measurements of the Holocene geologic slip rate of the Hayward fault are as much as 9 mm/yr (Lienkaemper and others 1989) - about 80% greater than the first Holocene measurements determined as recently …

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General Report, Loma Prieta Earthquake Sessions, Mary Ellen Hynes Mar 1991

General Report, Loma Prieta Earthquake Sessions, Mary Ellen Hynes

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

No abstract provided.

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Liquefaction Of Soils In The 1989 Loma Prieta Earthquake, Raymond B. Seed, Michael F. Riemer, Stephen E. Dickenson Mar 1991

Liquefaction Of Soils In The 1989 Loma Prieta Earthquake, Raymond B. Seed, Michael F. Riemer, Stephen E. Dickenson

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

The Loma Prieta Earthquake of October 17, 1989 was the most costly single natural disaster in U.S. history, resulting in losses of $7 to $9 billion, and claiming 63 lives. These damages were concentrated mainly at a number of distinct sites comprising a relatively small fraction of the affected region, as local site conditions and related geotechnical factors exerted a major influence on damage patterns and loss of life in this catastrophic event. This paper discusses one of these geotechnical factors, the widespread occurrence of soil liquefaction during the earthquake, as well as the associated damages and the resulting lessons …

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Performance Of Concrete Faced Earthdam To Loma Prieta Earthquake, Sukhmander Singh, Nick Pal Mar 1991

Performance Of Concrete Faced Earthdam To Loma Prieta Earthquake, Sukhmander Singh, Nick Pal

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

As a result of the shaking from the Loma Prieta Earthquake of 1989, the concrete lining of an earth embankment suffered cracking at numerous locations on its upstream side and developed in its bed lining, crater-like pot-holes ranging in size up to 10 ft. in diameter. Field investigation and preliminary studies indicated the differential dynamic vibrations of the earth embankment and the concrete lining to be the cause of the cracking, and the liquefaction of the underlying stratum below the bottom of the reservoir to be the cause of the pot-holes formed as a result of the pore pressure bursting …

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Prediction Of Loma Prieta Earthquake And Creation Of Awareness About It In Society, Arun Bapat Mar 1991

Prediction Of Loma Prieta Earthquake And Creation Of Awareness About It In Society, Arun Bapat

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

Prediction of earthquake as an exercise of academic interest is one activity. Creation of awareness about seismic disaster and its mitigation is more broad base social activity. It is necessary that the predicted seismic event is likely to occur, people in the vulnerable seismic area should be told about the utility of macroseismic, short-term reliable earthquake precursors, which could be observed by common man. The happenings involving both the above cases for Loma Prieta earthquake are discussed.

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Site Stratigraphy And Its Effects On Soil Amplification In The Greater Oakland Area During The October 17, 1989 Loma Prieta Earthquake, J. David Rogers Mar 1991

Site Stratigraphy And Its Effects On Soil Amplification In The Greater Oakland Area During The October 17, 1989 Loma Prieta Earthquake, J. David Rogers

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

No abstract provided.

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Study Of Co-Seismic Planetary Conditions For Earthquake Prediction, R. N. Ketkar, M. N. Viladkar, P. N. Agrawal Mar 1991

Study Of Co-Seismic Planetary Conditions For Earthquake Prediction, R. N. Ketkar, M. N. Viladkar, P. N. Agrawal

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

The periodicities in the occurrence of earthquakes, as indicated by the cosmic conditions, have been traced by analysing the planetary data at the time of occurrence of more than 1100 earthquakes of magnitude, M 27.0, which occurred during the period 1896 to 1965. Correlation between the transits of planets in the sensitive areas and at sensitive longitudes in the zodiac and the seismicity of California and adjoining area has been shown. Based on the analysis, a method for forecasting earthquakes is also proposed.

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The Loma Prieta Earthquake: Implications Of Structural Damage, S. A. Mahin Mar 1991

The Loma Prieta Earthquake: Implications Of Structural Damage, S. A. Mahin

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

The Loma Prieta earthquake provides a wealth of information on the seismic response of a wide variety of structures over a large metropolitan area. Soil amplification at sites distant from the epicenter contributed significantly to the substantial damages developed during the earthquake. Because of the large shaken area, the earthquake provides much useful information for all those interested in earthquake engineering. Structural damages resulting from the earthquake are reviewed herein with emphasis on buildings and bridges. Implications for modern design and retrofit methods are highlighted. Emphasis is placed on the need to carefully consider soil conditions, to treat the structure …

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Two Sequences Of Fine Grained Soil Liquefaction At Soda Lake, Pajaro River Valley, Santa Cruz County, California, J. David Rogers, C. J. Wills, M. W. Manson Mar 1991

Two Sequences Of Fine Grained Soil Liquefaction At Soda Lake, Pajaro River Valley, Santa Cruz County, California, J. David Rogers, C. J. Wills, M. W. Manson

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

Soda Lake was originally a natural lake in an abandoned meander bend of the Pajaro River. The San Andreas Fault zone lies 350 meters southwest of the lake, on a northwesterly trend. The natural lake was diked with embankments approximately 3 to 6 meters high on its 'southern and eastern sides in 1968 for use as a tailings pond. Fine waste material from Granite Rock Company's Wilson quarry, located just across the river and approximately 0.5 kilometers west of the lake, was periodically slurried by pipeline over to Soda Lake and thence hydraulically deposited from 1968 to the present. During …

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A Study On Pile Forces Of A Pile Group In Layered Soil Under Seismic Loadings, Hasegawa Masayuki, Nakal Shoichi Mar 1991

A Study On Pile Forces Of A Pile Group In Layered Soil Under Seismic Loadings, Hasegawa Masayuki, Nakal Shoichi

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

Characteristics of pile forces under seismic loadings are discussed from view points of the inertial interaction due to the mass effect of a superstructure and the kinematic interaction due to the resistance effect of piles against soil motions. A typical building supported on a pile group embedded in a layered soil, which has two- and four layer profiles, is chosen for studying the pile forces which imply the shearing force and bending moment. The earthquake response analysis is performed in accordance with the substructure method, in which the group effect of piles in the layered soil is appropriately included by …

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Characteristics Of Vertical Ground Motions Recorded During The Lorna Prieta Earthquake, Marshall Lew Mar 1991

Characteristics Of Vertical Ground Motions Recorded During The Lorna Prieta Earthquake, Marshall Lew

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

A study of a limited number of vertical ground motion acceleration-time histories recorded during the Loma Prieta earthquake of October 17, 1989 has been made. It has been found that maximum vertical ground motions may be greater than the horizontal ground motions in the near vicinity of the fault rupture zone. The limited records suggest that there is more spectral energy at very short structural periods in the vertical ground motions as compared with the horizontal ground motions. At longer periods, the vertical energy is significantly less, however, there is an increasing trend for very long structural periods.

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Considerations To Damage Patterns In The Marina District During The Loma Prieta Earthquake Based On Rayleigh Wave Investigation, Kohji Tokimatsu, Shoei Nomura, Shinichi Kuwayama, Shuji Tamura, Akio Abe Mar 1991

Considerations To Damage Patterns In The Marina District During The Loma Prieta Earthquake Based On Rayleigh Wave Investigation, Kohji Tokimatsu, Shoei Nomura, Shinichi Kuwayama, Shuji Tamura, Akio Abe

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

Rayleigh wave investigation is made in the Marina District to study geotechnical factors controlling the damage patterns in the Loma Prieta earthquake. A portable system has been developed for determining a Rayleigh wave dispersion curve based on the measurements of artificially induced ground vibration or microtremor. Five sites are selected along a line crossing the hydraulic fill zone in which structures and/or buried utilities were significantly damaged. An inverse analysis on the measured dispersion curves results in a cross section of shear wave velocity profiles in the District. Site amplification and liquefaction potential of each site are estimated and discussed …

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Contributed Papers: Discussions And Replies, T. Kagawa Mar 1991

Contributed Papers: Discussions And Replies, T. Kagawa

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

No abstract provided.

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Investigation Of Sanitary Landfill Slope Performance During Strong Ground Motion From The Loma Prieta Earthquake Of October 17, 1989, Mervin E. Johnson, Joan Lundy, Marshall Lew, Monte E. Ray Mar 1991

Investigation Of Sanitary Landfill Slope Performance During Strong Ground Motion From The Loma Prieta Earthquake Of October 17, 1989, Mervin E. Johnson, Joan Lundy, Marshall Lew, Monte E. Ray

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

This paper evaluates the performance of landfill slopes (refuse fill slopes) during strong ground motion from the October 17, 1989 Loma Prieta Earthquake (M7.1) that affected the Santa Cruz Mountains - San Francisco Bay region. The earthquake's occurrence in a highly populated area that contains the waste disposal sites for this large population offered a unique opportunity to review the performance of slopes on the landfills. Current state and federal regulations require the analysis of stability of landfills under seismic loading. To date, these evaluations have relied on gross simplified assumptions. This paper examines whether these assumptions are reasonably correct. …

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