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Full-Text Articles in Geotechnical Engineering
Impact Response Of Granular Soils, C. J. Poran, J. A. Rodriguez, K. S. Heh
Impact Response Of Granular Soils, C. J. Poran, J. A. Rodriguez, K. S. Heh
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The paper describes results from an extensive experimental model study of response of dry sand to impact of a rigid pounder. In the laboratory tests a circular steel pounder was repeatedly dropped on sand contained in a large tank. Measurements included pounder acceleration and soil pressure at impact, pounder settlement, and soil densities and strains. Effects of pounder drop height, weight and contact area were investigated. A method is presented for the evaluation of global dynamic stiffness of the so1l mass affected by the impact by calculating a dynamic settlement modulus (DSM). The DSM values are determined from integration of …
Soil Profiling By Spectral Analysis Of Surface Waves, T. Satoh, K. Yamagata, C. J. Poran, J. A. Rodriguez
Soil Profiling By Spectral Analysis Of Surface Waves, T. Satoh, K. Yamagata, C. J. Poran, J. A. Rodriguez
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Methods for in-situ surface measurement and spectral analysis of Rayleigh waves for subsurface soil investigation have been tried by several researchers in recent years. The two most common methods, steady-state Rayleigh-wave and spectral-analysis-of-surface-waves (SASW) have certain disadvantages and are not used for routine soil investigation. The paper presents a system which uses a controlled vibration source with amplitude modulation and variable frequency capabilities. The electromagnetic vibrator may be varied in size and weight according to the depth of the soil strata investigated. The Rayleigh wave phase velocity dispersion curves are used to compute apparent velocity distribution in depth. An approximate …
General Report Session 10: Wave Propagation In Soils, Chaim J. Poram
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.
A Study Of Blast Pressure From Underwater Borehole Blasting, T. S. Thandavamoorthy
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 …
Control Of Seismic Response Of Structures, Chris P. Pantelides
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 …
General Report Session 11: Dynamic Characteristics Of Vibration Sources Other Than Earthquakes, Toyoaki Nogami
General Report Session 11: Dynamic Characteristics Of Vibration Sources Other Than Earthquakes, Toyoaki Nogami
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
No abstract provided.
On Predictions And Performance Of Machine Foundations, George M. S. Manyando, Shamsher Prakash
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 …
Performance Of A Cement Silo Under Quarry Blast, Krishen Kumar, Gopal Ranjan, Shamsher Prakash
Performance Of A Cement Silo Under Quarry Blast, Krishen Kumar, Gopal Ranjan, Shamsher Prakash
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Behaviour of a 67 m tall R.C.C. twin storage-cum-blending cement silo has been studied under blast loads from a nearby limestone quarry. This paper reports the findings of the analytical and experimental studies and verification of the results of analysis by the measurements made on the prototype structure, which agreed within 10%. Acceleration response of the structure were recorded for a blast of 2.61 t having six delays with maximum charge per delay 800 kg. A series of small and large size blasts were conducted to establish relationship between peak ground acceleration and distance from the blast. Non-dimensional acceleration response …
Response Of Frame Foundations To Vertical Vibrations, P. J. Moore, T. P. Tan
Response Of Frame Foundations To Vertical Vibrations, P. J. Moore, T. P. Tan
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
A series of vertical vibration tests was carried out on small lm span steel portal frames of different stiffnesses and supported on two isolated rigid circular footings on a compacted sand deposit. Dynamic loading was applied to the center of the frame and the response was monitored by means of six accelerometers attached at various locations. The resonant frequency and the maximum amplitude of vibration were observed to be dependent on the frame stiffness and two theoretical models, the combined method and the dynamic deformation method, were used to compare calculated and observed results.
The Optimization Principles Of The System "Mass Blast-Protected Structure", Yugeni Borisov, Boris Pishkin
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.
Behavior Of Buildings In August 21, 1988 Bihar-Nepal Earthquake, S. K. Thakkar, D. K. Paul, S. Mukerjee, S. Bandyopadhyay, Ashwani Kumar, B. V. K. Lavania
Behavior Of Buildings In August 21, 1988 Bihar-Nepal Earthquake, S. K. Thakkar, D. K. Paul, S. Mukerjee, S. Bandyopadhyay, Ashwani Kumar, B. V. K. Lavania
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
A moderate size earthquake rocked Bihar-Nepal border at 4.40 hrs. on August 21, 1988 causing wide spread devastation leading to loss of many lives and economic loss to the people of that region. The paper describes the study of damages occurred in masonry buildings, reinforced concrete buildings and liquefaction of the soil. The weakness of construction causes of damage and lessons learnt from the performance of structures are highlighted. The traditional and old structures without any earthquake resistance measures has suffered greater damage. The new reconstruction and strengthening measures must take into consideration the experience of failure of structures.
Dedication To Harry B. Seed, Shamsher Prakash
Dedication To Harry B. Seed, Shamsher Prakash
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
No abstract provided.
Earthquake Potential Along The Hayward Fault, California, Glenn Borchardt, J. David Rogers
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 …
June 20, 1990 Earthquake Of Northern Iran: An Overview, F. Nateghi, S. Eshghi
June 20, 1990 Earthquake Of Northern Iran: An Overview, F. Nateghi, S. Eshghi
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
On the day of June 20, 1990 at 21:00 GMT (June 21, 1990, at 00:30 local time) a destructive earthquake of magnitude 7.6 shook Northern provinces of Iran. It caused widespread geotechnical and structural damages covering an approximate area of 10,000 sq. km resulting in 37,000 life losses, 100,000 injuries, and 100,000 building failures leaving more than 400,000 people homeless. This paper summarizes the post-earthquake investigations and discusses the general engineering aspects of the June 20, 1990 seismological, geotechnical, and structural aspects of the event. Lessons learned are also discussed.
Performance Of Earth Dams During The Loma Prieta Earthquake, Leslie F. Harder Jr.
Performance Of Earth Dams During The Loma Prieta Earthquake, Leslie F. Harder Jr.
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The October 17, 1989 Lorna Prieta Earthquake shook a large number of earth and rockfill darns. There were actually more than 100 darns within 50 miles of the fault rupture associated with this event. Although more than half of these embankments were less than 60 feet in height, a number of major darns were strongly shaken. In general, the darns performed satisfactory with one major darn and one minor darn developing moderate damage. A small number also developed minor to moderate cracking which required repairs. The great majority, however, sustained no significant damage. Although this result is quite encouraging, this …
Study Of Co-Seismic Planetary Conditions For Earthquake Prediction, R. N. Ketkar, M. N. Viladkar, P. N. Agrawal
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.
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
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 …
Dynamic Soil – Pile Parameters, K. Muthukrishnaiah, V. S. Raju
Dynamic Soil – Pile Parameters, K. Muthukrishnaiah, V. S. Raju
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Results of lateral dynamic load tests conducted on precast driven concrete piles at two Project sites, one in South India (two individual piles) and another in Western India (one individual pile and two numbers of two-pile groups) are reported in the Paper. Shear wave velocities were determined from Cross Hole tests at the pile cut-off level at the test pile locations at the two sites. These values are compared with those reported in literature for two similar types of soils, namely, alluvial clay and alluvial sand. The subsoil conditions including Standard Penetration Test data and Static Cone Penetration Test data …
Preliminary Report On The Geotechnical Aspects Of The Philippine Earthquake Of July 16, 1990, Kohji Tokimatsu, Shinichi Kuwayama, Saburoh Midorikawa, Akio Abe, Shuji Tamura
Preliminary Report On The Geotechnical Aspects Of The Philippine Earthquake Of July 16, 1990, Kohji Tokimatsu, Shinichi Kuwayama, Saburoh Midorikawa, Akio Abe, Shuji Tamura
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The Philippine earthquake of July 16, 1990 (MS = 7.8), of which epicenter is about 100 km north of Manila city, was one of the most costly single natural disasters in Philippine history. The loss of life of over 1,600 persons resulted. Extensive damage to buildings, roads, embankments, natural slopes, and bridges was observed in a widespread area of approximately 20,000 square kilometers. One of the major causes of the damage was liquefaction of various sandy soils including artificially fills, alluvial deposits of river delta, and sandbars. This paper presents a preliminary overview of damage aspects of the earthquake, …
Soil Amplification At Treasure Island During The Loma Prieta Earthquake, Roman D. Hryciw, Scott E. Shewbridge, Kyle M. Rollins, Michael Mchood, Matthew Homolka
Soil Amplification At Treasure Island During The Loma Prieta Earthquake, Roman D. Hryciw, Scott E. Shewbridge, Kyle M. Rollins, Michael Mchood, Matthew Homolka
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The Loma Prieta Earthquake ground motions recorded on Treasure Island, a man-made fill in San Francisco Bay were considerably greater than on the adjacent Yerba Buena rock outcrop. The Yerba Buena motions were used as input to the computer program SHAKE90 for computing soil amplification at Treasure Island. Shear wave propagation velocities were obtained by seismic cone penetration testing. Reasonable agreement was observed between the computed and recorded accelerations at the strong motion recording station. The maximum computed accelerations around the island ranged from 0.13 to 0.20 g's. The degree of damage at various locations on the island correlated somewhat …
General Report Session 5: Soil-Structure Interaction Under Dynamic Loading, E. Kausel, J. Roesset, A. H. Hadjian, J. Bielak, G. R. Martin
General Report Session 5: Soil-Structure Interaction Under Dynamic Loading, E. Kausel, J. Roesset, A. H. Hadjian, J. Bielak, G. R. Martin
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
No abstract provided.
Structural Damage In A Populated Area Due To An Active Fault, N. Kalteziotis, N. Sabatakakis, G. Koukis, H. Zervogiannis, G. Tsiambaos
Structural Damage In A Populated Area Due To An Active Fault, N. Kalteziotis, N. Sabatakakis, G. Koukis, H. Zervogiannis, G. Tsiambaos
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The city of Patras was struck in August 1989 by a shallow earthquake of MS= 4.8 which caused a surface rupture and serious structural damage to several buildings located in a narrow elongated zone. A detailed investigation programme was carried out including geological mapping, drilling of boreholes, in situ and laboratory testing and monitoring of horizontal and vertical movements. It was found that the surface rupture, about 1500 m long, was closely related with the reactivation of a preexisting normal fault. The structural damage of buildings was found to be limited mainly in a narrow zone 50 m …
Validation Of A Piles Dynamic Analysis Computer Code Through In Situ Tests, R. Bonaz, A. Pecker, T. Duroy, M. Ralljaona, J. P. Touret
Validation Of A Piles Dynamic Analysis Computer Code Through In Situ Tests, R. Bonaz, A. Pecker, T. Duroy, M. Ralljaona, J. P. Touret
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
In order to qualify the CLAPIFOU code, which computes the dynamic response of a pile foundation subjected to earthquake or harmonic forces, a test campaign was carried out on piles, to full scale, on pile groups of 2 x 1 piles and 2 x 3 piles on the Plancoet site. The purpose of the study is to compare the results of the experiments and the digital simulations with the computer code. The comparison is good but confirms the need for a good knowledge of the soil's characteristics.
Aspects Of Seismic Analysis And Design Of Rockfill Dams, George Gazetas, Panos Dakoulas
Aspects Of Seismic Analysis And Design Of Rockfill Dams, George Gazetas, Panos Dakoulas
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Theoretical methods for estimating the dynamic response and predicting the performance of modern rockfill dams subjected to strong earthquake shaking are reviewed. The focus is on methods accounting for nonlinear material behavior, for 3-Dimensional canyon geometry, and asynchronous base excitation. It is shown that both strong nonlinearities and lack of coherence in the seismic excitation tend to reduce the magnitude of the deleterious "whip-lash" effect computed for tall dams built in rigid-wall narrow canyons. Particular emphasis is accorded to Concrete-Faced Rockfill dams and a case study involving an actually designed dam in a narrow canyon points to some potential problems …
Classification Of Analysis Methods For Dynamic Soil-Structure Interaction, John P. Wolf
Classification Of Analysis Methods For Dynamic Soil-Structure Interaction, John P. Wolf
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The various methods to perform soil-structure-interaction analysis are classified. The first classification uses as criterion the behavior (linear or nonlinear) of the structure and of the unbounded soil. The second classification distinguishes between the direct method and the substructure method, which do not necessarily lead to identical results. Within each method, however, the various procedures are mathematically equivalent. In the substructure method the dynamic stiffness representing the interaction forces of the unbounded soil is determined based on the boundary element method in the time or frequency domain. In the latter case various so-called realizations in the time domain are distinguished …
State Of The Art Papers: Discussion And Replies, Tzou-Shin Ueng
State Of The Art Papers: Discussion And Replies, Tzou-Shin Ueng
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
No abstract provided.
Seismic Design Of Earth Retaining Structures, R. V. Whitman
Seismic Design Of Earth Retaining Structures, R. V. Whitman
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Recent experiments, field observations and theoretical numerical studies are summarized: Where the simple conditions assumed by the Mononobe-Okabe theory are reproduced. ln tests, predictions and observations agree well. However, a retaining structure and surrounding soil are a complex dynamic system and behavior is far from simple. Emphasis has shifted somewhat away from dynamic stresses toward evaluation of residual displacements. With a good understanding of actual behavior, traditional methods may still be used except for large and unusual structures. The largest unknowns concern the behavior of cohesive soils and moderately dense to dense saturated sands.
Preface, Shamsher Prakash
Preface, Shamsher Prakash
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
No abstract provided.
Welcoming Remarks, Joseph E. Minor
Welcoming Remarks, Joseph E. Minor
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
No abstract provided.
Pictures And Participants, Multiple Members
Pictures And Participants, Multiple Members
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
No abstract provided.