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Full-Text Articles in Geotechnical Engineering
The Role Of Rotational Shear In Site Response Analyses, X. S. Li, C. K. Shen
The Role Of Rotational Shear In Site Response Analyses, X. S. Li, C. K. Shen
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Rotational shear is a class of loading under which the second invariant of the deviatoric stress tensor, J, is kept constant during shear. A limited number of undrained tests on saturated loose sand have shown that rotational shear yields more pore pressure than other shear paths of the same J magnitude. By intuition, this experimental finding seems to suggest that soil subjected to multi-directional earthquake loading, which bears the characteristics of the rotational shear, has lower liquefaction resistance than that under unidirectional shaking. However, in contrast to intuition, a preliminary but careful examination of the field stress and boundary conditions …
Seismic Response Of 20-Valleys: Local Site Effects, K. E. Loukakis, J. Bielak
Seismic Response Of 20-Valleys: Local Site Effects, K. E. Loukakis, J. Bielak
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Layering and geometry effects on ground response of two-dimensional sedimentary valleys under oblique seismic excitation are investigated. The seismic wave has the shape of a half cycle incoming pulse with SV-wave characteristics. Vertical and oblique incoming signals of varying duration are used. The analysis is performed using finite element techniques, an equivalent effective force method to prescribe the free field motion within the domain of computation, and an artificial boundary to absorb the scattered motion. Simple examples are presented confirming the validity of this methodology. It is shown that surface waves generated at the valley edges propagate through the basin …
The Dahshour (Egypt) Earthquake Of 12th Of October 1992, M. M. Soliman
The Dahshour (Egypt) Earthquake Of 12th Of October 1992, M. M. Soliman
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
On the 12th of October, 1992 an earthquake of 5. 7 moment magnitude hit Dahshour (Egypt) and the surrounding area. The characteristics of the building stock exposed to this earthquake is firstly presented in the paper. Then, the Dahshour earthquake is discussed in terms of the lessons that can be learned by engineers. The paper presents a short description of the geotechnical effects and the observed patterns of damage of the existing building categories and monuments. Finally, a list of the most important conclusions is introduced.
Scaling Earthquake Motions In Geotechnical Design, M. D. Trifunac
Scaling Earthquake Motions In Geotechnical Design, M. D. Trifunac
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The traditional approach to scaling earthquake ground motion for geotechnical design applications is based on peak ground acceleration. This approach is useful when the physics of the problem depends linearly only on the nature of the high frequency (short wavelength) inertial part of strong motion. For nonlinear response analyses, the representative strain (~ velocity) and the number of stress reversals (~ duration of shaking) must also be considered. For long (large) structures (bridges and dams), the relative displacement of multiple foundations and the quasi-static deformation of the complete structure may contribute to the largest design levels. Thus, the modern design …
A New Seismic-Geotechnical Strong Motion Approach, Francois E. Heuze, Tzou-Shin Ueng, Lawrence J. Hutchings, Stephen P. Jarpe, Paul W. Kasameyer
A New Seismic-Geotechnical Strong Motion Approach, Francois E. Heuze, Tzou-Shin Ueng, Lawrence J. Hutchings, Stephen P. Jarpe, Paul W. Kasameyer
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
We have developed a new approach to estimate site-specific strong motion due to earthquakes on specific faults or source zones. It combines seismologic and geotechnical studies. It entails obtaining records of small earthquakes at the site, both at the surface and downhole in bedrock, as well as performing geotechnical dynamic site characterization. This new approach has the dual result of providing an optimized definition of the dynamic geotechnical site properties and providing calculated free-field, strong motion estimates. The procedure is demonstrated at the Painter Street Bridge site in Rio Dell, CA, for which we provide a range of surface motions …
Damage To Agricultural Facilities Caused By The 1993 Kushiro-Oki And Hokkaido Nansei-Oki Earthquakes, S. Tani
Damage To Agricultural Facilities Caused By The 1993 Kushiro-Oki And Hokkaido Nansei-Oki Earthquakes, S. Tani
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Two large earthquakes struck Japan during only a 6 month period in 1993: Kushiro-oki on January 15 and Hokkaido Nansei-oki on July 12. Both caused a lot of damage to facilities, including installations such as farm roads, reclaimed farmland, channels, head works, drainage pump stations, pipelines and fill dams. In this paper, we present an outline of the damage to agricultural facilities and its features.
Review Of Geotechnical Investigations Resulting From The Roermond April 13, 1992 Earthquake, P. M. Maurenbrecher, A. Den Outer, H. J. Luger
Review Of Geotechnical Investigations Resulting From The Roermond April 13, 1992 Earthquake, P. M. Maurenbrecher, A. Den Outer, H. J. Luger
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
In 1987 the Engineering Geology section of the Delft University of Technology carried out a survey of the SE Netherlands to determine which areas were susceptible to liquefaction based on soil profile, groundwater levels and a Richter scale magnitude 6 earthquake along the principal rift fault through the Netherlands, the Peelrand fault system. The fault system has been active since the Triassic and forms part of the Rhine-North Sea rift system. The last major earthquake along the Peelrand fault was in 1933. Recently, in 1992, A 5.8 magnitude earthquake occurred at Roermond, near to the Dutch-German border. Though damage resulting …
Dynamic Modeling Of Layered Systems To Moving Surface Loads: Applications, Raj Siddharthan, Gary M. Norris, Mahmoud El-Gamal
Dynamic Modeling Of Layered Systems To Moving Surface Loads: Applications, Raj Siddharthan, Gary M. Norris, Mahmoud El-Gamal
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Two important application of a recently developed moving load model are described. The model uses an efficient semi analytical "finite layer" formulation of the porous medium. One application is a response of a layered sandy nonlinear porous medium, while the other is a viscoelastic pavement layer system. The study reveals that the properties of the layers and porefluid and the moving velocity of the load are important factors that affect the response of the layered system.
Scattering Of Sh-Waves By Arbitrary Surface Topography, M. E. Manoogian, V. W. Lee
Scattering Of Sh-Waves By Arbitrary Surface Topography, M. E. Manoogian, V. W. Lee
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The weighted residual method was applied to the problem of scattering and diffraction of plane SH-waves by a shallow alluvial valley of arbitrary shape on the surface of a two-dimensional half-space. The formulation was also applied to the case of a shallow canyon. In order to demonstrate the versatility of the method, it was applied to shallow circular, shallow elliptical, and shallow rectangular canyons and alluvial valleys. Results obtained for the cases of a semi-cylindrical and a shallow semi-elliptical valleys and canyons match those obtained using closed form solutions. It was shown that significant ground motion amplifications, with respect to …
Theoretical Investigations On The Nakamura's Technique, C. Lachet, P. Y. Bard
Theoretical Investigations On The Nakamura's Technique, C. Lachet, P. Y. Bard
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
We use synthetic calculations to investigate the spectral ratio between horizontal and vertical components (H/V ratio), derived from noise simulation, in order to appreciate the reliability of the so-called Nakamura's method for site effects applications. This ratio shows a peak whose position generally coincides with the fundamental resonance frequency. We show that this position is independent of the source function, whereas it is characteristic of the geological structure. We also compare these results with those obtained for vertical S waves and Rayleigh waves, in order to better understand the significance of this HIV peak. Finally, we show that the amplitude …
Stress Wave Propagation In Unsaturated Sands, G. E. Veyera, C. A. Ross
Stress Wave Propagation In Unsaturated Sands, G. E. Veyera, C. A. Ross
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Wave transmission tests were conducted on specimens of Eglin and Ottawa 20-30 sands at saturations varying from dry to near 100% using a Split-Hopkinson Pressure Bar. Specimens were compacted to a constant dry density in a thick-walled stainless steel container using a standard Proctor hammer. Compacted specimens were loaded in undrained, dynamic uniaxial confined compression at strain rates of approximately 13/s to 19/s. Tests were conducted on dry specimens; specimens compacted moist and tested moist; specimens compacted moist and dried before testing. For a constant input stress, transmitted stress and compressional wave propagation velocity were seen to vary with saturation. …
Longitudinal Waves In A Rod In An Elastic Medium, A. Bodare, I. K. Eriksson, K. Samuelsson
Longitudinal Waves In A Rod In An Elastic Medium, A. Bodare, I. K. Eriksson, K. Samuelsson
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The general equations for the propagation of longitudinal waves in an infinite cylindrical rod including the effect of a surrounding elastic medium have been derived in order to obtain the relationship between the circular frequency and the wave number. A comparison has then been made with the Smith model in order to investigate the limits of the model and to refine the expressions for the spring and damming constants.
Dispersion Of Longitudinal Waves Propagating In A Continuum With Randomly Perturbated Parameters, J. Náprstek
Dispersion Of Longitudinal Waves Propagating In A Continuum With Randomly Perturbated Parameters, J. Náprstek
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The author investigates the propagation of wave motion in a continuum the material parameters of which are random functions of longitudinal coordinate. The analysis is based on the theory of Markov processes and the subsequent solution on the respective Fokker-Planck-Kolmogorov equation. The fully deterministic response in the excitation point transforms into nonhomogeneous random process in the longitudinal coordinate with the growing distance. The quota of the deterministic component in overall response drops until it disappears completely. The model of uncorrelated imperfections (white noise) of the continuum is inacceptable, because it is at variance with the energy equilibrium law. The results …
Response Of Alluvial Valleys To Incident Sh, Sv And P Waves, S. Ahmad, K. L. Fishman, H. Xue
Response Of Alluvial Valleys To Incident Sh, Sv And P Waves, S. Ahmad, K. L. Fishman, H. Xue
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Results of an extensive numerical study on two dimensional wave scattering by valleys of semi-elliptical cross section due to incident SH, SV and P waves are presented. The investigation has been conducted using a rigorous Boundary element algorithm. The influence of key parameters, such as, valley depth, impedance ratio, frequency, and angle of incidence on surface ground motion are studied in detail. Furthermore, the case of a valley within a layered half space is analyzed and results compared with those obtained for a valley within a homogeneous half space.
Effect Of Magnitude And Type Of Damping On Soil Amplification, Jose M. Roesset, Carlos I. Huerta, Kenneth H. Stokoe Ii
Effect Of Magnitude And Type Of Damping On Soil Amplification, Jose M. Roesset, Carlos I. Huerta, Kenneth H. Stokoe Ii
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Soil Amplification studies conducted to obtain site specific seismic motions at the free surface of a soil deposit or at any other elevation (convolution process), or to determine compatible base motions at a given depth for soil structure interaction analyses (deconvolution) assume, when performed in the frequency domain simulating nonlinear soil behavior through an iterative linear analysis, that the internal soil damping is of a linear hysteretic nature. This tends to filter out excessively the high frequency components of motion for convolution studies and leads to eventual instability of the solution at a given depth (function of the soil properties) …
Discussions And Replies — Session X, Multiple Authors
Discussions And Replies — Session X, Multiple Authors
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
No abstract provided.
Simple Model For Active Isolation Of Machine Foundations By Open Trenches, S. Ahmad, T. M. Ai-Hussaini
Simple Model For Active Isolation Of Machine Foundations By Open Trenches, S. Ahmad, T. M. Ai-Hussaini
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Ground disturbance due to waves generated by a machine foundation can be detrimental to adjacent structures or operation of sensitive equipment nearby. For machine foundations vibrating at moderate to high frequencies, the amplitude of ground motion can be reduced significantly by installing a wave barrier around the source. A three-dimensional boundary element algorithm incorporating quadratic elements has been used to perform an extensive parametric study on the effectiveness of open trenches as wave barriers. Based on the results of the study, a simple model in the form of an algebraic expression is developed for estimating the vibration screening effectiveness of …
Assessment Of Ground Vibration From Passing Train, Ján Benčat
Assessment Of Ground Vibration From Passing Train, Ján Benčat
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Increasing demands on speed increase, higher axle on transportation over dimensional and heavy loads cause simultaneous increase of unfavorable traffic effect on the structures of railways and on the train-induced ground vibration, respectively. This paper examines the residual problems of ground-borne vibration, the vehicle and track features which might be responsible for generation, how it is propagated, and how it might affect. A few of experimental results which have been obtained during studies made on Slovak Railways (ZSR) are presented in the paper, too.
Dynamic Behavior Of Beijing Sandy Clay And The Dynamic Responses Of Beijing Subway To Traffic Vibrations, C. S. Pan, W. Cui, D. Li, F. Gao
Dynamic Behavior Of Beijing Sandy Clay And The Dynamic Responses Of Beijing Subway To Traffic Vibrations, C. S. Pan, W. Cui, D. Li, F. Gao
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Experiments were carried out for the Beijing sandy clay using a triaxial apparatus Model DTC- 240 (JAPAN) with the dynamic characteristics of the soil obtained and formulated. The test data were applied to the 2-D and 3-D finite element analyses for the dynamic responses of Beijing Subway to traffic vibrations. Resulte acquired from the numerical analyses happened to be in good coincidence with the measured responses.
Development Of New Stiffness And Damping Expressions For Footing Vibrations, H. V. P. Truong, P. J. Moore
Development Of New Stiffness And Damping Expressions For Footing Vibrations, H. V. P. Truong, P. J. Moore
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
New expressions for stiffness and radiation damping, which have been developed for a new forcing function, are based on the simple equation of wave propagation in a perfectly elastic half space for different modes of vibrations, particularly vertical and horizontal vibrations. A differential equation including the effect of foundation mass is presented and the results of the amplitudes of vibration obtained from this differential equation are compared with those in the standard differential equation in soil dynamics textbooks. Furthermore, added soil masses for vertical and horizontal vibrations are also derived based on the equation of wave propagation and discussed with …
Response Of Embedded Circular Flexible Foundations, N. Gucunski
Response Of Embedded Circular Flexible Foundations, N. Gucunski
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The stiffness matrix approach to the solution of vertical vibrations of a circular flexible foundation embedded in a viscoelastic layered half-space have been described. Results of a parametric study, represented by displacement and soil reaction distributions and impedances, indicate a significantly different responses of flexible and rigid foundations. Important parameters are identified and include: the stiffness ratio, depth of embedment, soil stratification and loading distribution. Influence of each of the parameters is discussed.
Vibrations Of Impact Machine Foundations And Footing Settlements, M. R. Svinkin
Vibrations Of Impact Machine Foundations And Footing Settlements, M. R. Svinkin
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Foundations under machinery that produce impact loads, such as in forge shops, are major industrial sources of wave propagation in soil. The resulting vertical soil vibrations may cause dynamic settlements of column footings. Analyzing of a number of case histories shows that dynamic settlements of footings under columns and connected with them exterior walls at forge shops occur relatively slowly when the soil conditions are different from saturated sands. There are other causes of extensive damage of shop exterior walls. For predicting the dynamic settlements from new machine foundations, it is necessary to know expected footing vibrations. These vibrations can …
Interaction Of Adjacent Vibratory Machines, J. P. Lee, J. A. Bohinsky
Interaction Of Adjacent Vibratory Machines, J. P. Lee, J. A. Bohinsky
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Due to inevitable unbalanced masses that always exist, a rotating machine will experience vibration to various extent depending on the characteristics of loads and support conditions. When two pieces of vibratory machines are installed close to each other, the vibration of either machine may further be amplified by the interaction between the two machines. In this paper, the interaction effect between two adjacent vibratory machines supported on a flexible floor was investigated. It was found that for the case investigated, the most critical condition occurred when the unbalanced forces were out-of-phase.
The Reliability Aspects In Dynamic Engineering, G. Singh, B. M. Das
The Reliability Aspects In Dynamic Engineering, G. Singh, B. M. Das
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Strides in dynamic engineering need to be accompanied by developments in risk appraisal of designs so as to respond to rapidly increasing sensitivity to and awareness of hazards. A practical, reliable and engineer-friendly methodology for design is presented in light of the critical review of the various current practices. An example is presented to illustrate the advantages of the preferred approach to improving, unifying and rationalizing design.
Steady Vibration Of Flexible Circular Plate On An Elastic Half Space, X. Zeng, X. Qin, P. Gong, M. Iguchi
Steady Vibration Of Flexible Circular Plate On An Elastic Half Space, X. Zeng, X. Qin, P. Gong, M. Iguchi
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The steady vibration of a flexible circular plate with finite rigidity resting on an elastic half space and subjected to harmonic vertical loads on the surface of the plate is studied in the present paper. The contact between the plate and the half space is assumed to be frictionless. Three types of load are considered: 1. the load uniformly distributed over the entire surface of the plate, 2. the load uniformly distributed over a ring zone of the surface of the plate, 3. the concentrated load applied at the center of the plate. By expanding the distribution of the contact …
Non-Linear Response Of Foundation Systems Subjected To Vertical Machine Type Loading, Hatem Eibastawisy, Shamsher Prakash
Non-Linear Response Of Foundation Systems Subjected To Vertical Machine Type Loading, Hatem Eibastawisy, Shamsher Prakash
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Vertical vibration tests on surface and embedded footings of different dimensions were performed by Fry (1963) and Beredugo (1971). Analytical predictions were reported by Manyando (1991) based on nonlinear, frequency independent stiffness and damping coefficients for surface foundations. The authors present, in this paper, a mathematical model for predicting the response, in terms of amplitude versus frequency, for surface or embedded, irregular shaped foundations system under vertical vibration considering soil non-linearity and frequency dependent stiffness and geometrical damping parameters. The frequency dependent stiffness and geometrical damping parameters are based on Gazetas's work (1991). The predicted and measured natural frequency and …
Coupled Horizontal And Rocking Vibration Of Block Foundations, Sanjeev Kumar, Shamsher Prakash
Coupled Horizontal And Rocking Vibration Of Block Foundations, Sanjeev Kumar, Shamsher Prakash
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The computation of coupled response of block foundations subjected to a constant magnitude harmonic horizontal force or moment or both, is very important for the design of block foundations. Mathematical relationships for computing response of rigid block foundations using the elastic half-space method lite available but are not in an easily understandable format. More over relationships available for embedded foundation are for the case when both horizontal force and moment are acting on the foundation. To extract the solution for the case when either horizontal force or moment alone is acting from the existing relationships is extremely difficult, if not …
The Northridge Earthquake Of 1994: Ground Motions And Geotechnical Aspects, M. K. Yegian, G. V. Ghahraman, G. Gazetas, P. Dakoulas, N. Makris
The Northridge Earthquake Of 1994: Ground Motions And Geotechnical Aspects, M. K. Yegian, G. V. Ghahraman, G. Gazetas, P. Dakoulas, N. Makris
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Following the January 1994 Northridge Earthquake in Southern California, the authors traveled to Los Angeles and surveyed the earthquake damage region. Subsequently, seismologic, geologic and ground motion data were compiled and evaluated. This paper presents our observations and evaluation of: geologic and soil effects; soil-structure interaction; liquefaction; slope failures and rock slides; and ground deformations.
Performance Of Shored Earth Retaining Systems During The January 17, 1994, Northridge Earthquake, Marshall Lew, Ebrahim Simantob, Martin B. Hudson
Performance Of Shored Earth Retaining Systems During The January 17, 1994, Northridge Earthquake, Marshall Lew, Ebrahim Simantob, Martin B. Hudson
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The performance of several temporary deep shored earth retaining systems during the January 17, 1994 Northridge earthquake in Southern California is documented. These shoring systems ranged from 30 to 70 feet in depth and were subjected to severe ground motions with little deflection or distress.
Northridge Earthquake — Van Norman Complex Ground Movement, C. A. Davis, J. P. Bardet
Northridge Earthquake — Van Norman Complex Ground Movement, C. A. Davis, J. P. Bardet
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The January 17, 1994, Northridge Earthquake severely shook the Van Norman Complex, in the northern San Fernando Valley. Located in the nearfield, over the vicinity of the ruptured fault, the Van Norman Complex was subjected to many types of ground movements, including strong ground motions, tectonic displacements, ground deformation of natural soil deposits, and deformation of embankments and other engineered fills. The complex provides a well-documented case of how these various types of ground movements interact and their effects on engineered facilities. Throughout the complex, sand boils, liquefaction induced lateral spreading, and ground cracks were observed. Eleven water retaining embankments, …