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Full-Text Articles in Geotechnical Engineering
Representative Earthquake Features In The New Madrid Seismic Zone As Seen By Participants In The March 15-17, 1991, Field Trip, David Stewart
Representative Earthquake Features In The New Madrid Seismic Zone As Seen By Participants In The March 15-17, 1991, Field Trip, David Stewart
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
No abstract provided.
Application Of The Elastoplastic-Viscoplastic Bounding Surface Model To Cyclic Loading, Victor N. Kaliakin
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.
Behavior Of Geotextile Reinforced Soil Under Cyclic Loading, G. Venkatappa Rao, G. P. Singh, K. K. Gupta
Behavior Of Geotextile Reinforced Soil Under Cyclic Loading, G. Venkatappa Rao, G. P. Singh, K. K. Gupta
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The vast potential of geotextiles for separation (reinforcement in pavements and rail roads is yet to be fully exploited in India, despite the initial successful trials. This is partly due to the lack of sufficient test data on the behavior under repetitive loading of indigenous geotextiles. This paper reports typical triaxial test results on reinforced and unreinforced specimens before and after cyclic loading. The reinforcement used is a needle punched polypropylene geotextile manufactured in India. The results reported include strength before and after cyclic loading (cyclic loading under both drained and undrained conditions), modulus of resilience and plastic strain. Limited …
Cyclic Undrained Behavior Of An Undisturbed Gravel For Aseismic Design Of A Bridge Foundation, Fumio Tatsuoka, Shin-Lchi Yamada, Katsuhiko Yamada, Masahiko Yasuda, Susumu Manabe
Cyclic Undrained Behavior Of An Undisturbed Gravel For Aseismic Design Of A Bridge Foundation, Fumio Tatsuoka, Shin-Lchi Yamada, Katsuhiko Yamada, Masahiko Yasuda, Susumu Manabe
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
For the aseismic design of a pier foundation constructed on a lightly cemented dense gravel deposit of a 3,910m-long suspension bridge, cyclic and monotonic undrained triaxial tests were performed on undisturbed specimens with a diameter of 30cm taken from the deposit under a sea depth of about 55m. Using the results of the cyclic undrained triaxial tests together with irregular cyclic stresses evaluated for the design earthquake motion by a dynamic FEM analysis, maximum strains in the gravel deposit were obtained by the cumulative damage concept. The strain values thus estimated indicated a sufficiently high degree of seismic stability of …
Cyclic Undrained Behavior Of Saturated Sand Under Monotonic Loading, Hiroshi Matsuzawa, Masahiro Sugimura
Cyclic Undrained Behavior Of Saturated Sand Under Monotonic Loading, Hiroshi Matsuzawa, Masahiro Sugimura
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
In order to investigate undrained behavior of saturated sand, three types of undrained triaxial tests were performed for saturated Toyoura sand, i.e., cyclic loading test with (DTU-test) and without (DU-test) constant initial shear stress and tests in which constant rate axial strain and cyclic axial stress were applied to a specimen simultaneously (DCU-test). In DCU-tests, three types of failure were observed, i.e.; 1) perfectly liquefied in the case of relatively loose sand, 2) initially liquefied, but shear failure was induced after strength recovery for succeeding loading in the case of relatively dense sand, and 3) shear failure was induced without …
Cyclic Undrained Tests Along Constant Axial Stress On Hollow Cylinder, O. Hameury, T. Doanh
Cyclic Undrained Tests Along Constant Axial Stress On Hollow Cylinder, O. Hameury, T. Doanh
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Cyclic hollow cylinder tests have been performed on sand and clay under undrained conditions. In order to point out the effects of the rotation of principal axes, a constant axial stress is maintained during the application of torsional shear. On this stress path, the behavior of the two materials is studied in terms of stress-strain relationship, pore pressure, failure criterion and also rotation of strain principal axes.
Deformation Of Sand Under Cyclic Simple Shear Loading, Chung-Jung Lee
Deformation Of Sand Under Cyclic Simple Shear Loading, Chung-Jung Lee
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The deformation behavior of sand under simple shear loading was studied. The relation between the shear stress ratio and fabric factor, and the relationship between the fabric and dilatancy rate of a sand were developed. Thus the stress-dilatancy relation for sand was derived. Adopting the concept that the volumetric changes of the sample induced by the cyclic shear stress were compensated by the volumetric changes due to vertical stress changes in the constant volume simple shear tests, the relation of shear stress ratio and vertical stress change was derived.
Degradation Of Saturated Clays After Cyclic Loading, Tamotsu Matsui, Mohamed A. Bahr, Nobuharu Abe
Degradation Of Saturated Clays After Cyclic Loading, Tamotsu Matsui, Mohamed A. Bahr, Nobuharu Abe
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
This paper presents a part from a series of tests performed to evaluate the static shear behavior of normally consolidated and over-consolidated clays after cyclic loading effect. The results demonstrated that the static undrained stress-strain behavior of these types of clays was affected by their relative stiffness. Based on the equivalent over-consolidation hypothesis and the experimental results it was able to construct the shear characteristics degradation relationships for the normally consolidated clays. The predicted results were compared with the measured test data and their well agreement was confirmed.
Development Of Shear Modulus Reduction Curves Based On Lotung Downhole Ground Motion Data, C.-Y. Chang, Y. K. Tang, C. M. Mok, H. T. Tang, M. S. Power, J. C. Stepp
Development Of Shear Modulus Reduction Curves Based On Lotung Downhole Ground Motion Data, C.-Y. Chang, Y. K. Tang, C. M. Mok, H. T. Tang, M. S. Power, J. C. Stepp
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
In this study, equivalent shear moduli (or shear-wave velocities) and their variations with shearing strain at the Lotung seismic experiment site were back-calculated from recorded downhole array ground motions. Ground motion data for various levels of shaking (peak ground surface accelerations ranging from 0.03g to 0.21g) recorded during seven earthquakes were used in the analyses. Results show that downhole array ground motion data can be used to infer in-situ dynamic soil properties over a wide strain range.
Electrical Conductivity For Evaluating Fabric And Mechanical Behavior Of Granular Soils, Lien Kwei Chien, J. C. Li
Electrical Conductivity For Evaluating Fabric And Mechanical Behavior Of Granular Soils, Lien Kwei Chien, J. C. Li
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
In this study, an auto-compensation conductivity measurement system has been developed. This system is expected to offer a possible means for describing the granular soil fabric and mechanical behaviors. A series of cyclic triaxial compression, extension, and unloading tests with resistance measurement were performed. The correlation between granular soil friction angle φ, and vertical formation factor, Fv under maximum shear stress ratio has been studied. The test results have shown that the electrical conductivity could be used to evaluate the fabric behavior during the process of loading. The fabric ellipsoid function, which has been used to simulate the orientation …
In Situ Torsional Cylindrical Shear Test-Laboratory Results, W. Henke, R. Henke
In Situ Torsional Cylindrical Shear Test-Laboratory Results, W. Henke, R. Henke
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
We present results from cyclic tests conducted in the laboratory using a prototype in situ cyclic torsional cylindrical shear geotechnical testing system. The system is intended to advance our ability to design critical systems to resist earthquakes by improving our ability to analytically predict the behavior of soil-structure-equipment systems during earthquakes. It is to do so by providing, more reliably than we feel is now possible, estimates of the in situ cyclic shear stress vs strain characteristics needed by refined earthquake analyses. These characteristics include 1) resistances to initial liquefaction, cyclic degradation, and large cyclic deformations, and 2) undegraded, nonlinear, …
Lnsitu Measurement Of Damping Of Soils, W. P. Stewart, R. G. Campanella
Lnsitu Measurement Of Damping Of Soils, W. P. Stewart, R. G. Campanella
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The Seismic Cone Penetration Test (SCPT) has been shown to give reasonable results for insitu measurements of shear wave velocity, and this paper extends this work to include measurements of damping. The relevant equations of motion are described, factors affecting amplitude decay are discussed, and the nature of damping is summarized. Consideration is given to some of the practical aspects of pre-processing of signals. Three methods of damping calculation are presented. The first two, attenuation coefficient and modified SHAKE methods, require the application of amplitude corrections, which is not straight-forward, give variable results, and indicate negative damping in a clayey …
Lumped Parameters In Permanent Displacement, H. V. Phuong Truong
Lumped Parameters In Permanent Displacement, H. V. Phuong Truong
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
New dynamic spring and damping values, which are dependent on the frequency, have been introduced into calculations of horizontal permanent displacement. The new dynamic damping value, which is inversely proportional to the circular frequency, has the same form as the material damping, while the new value of stiffness increases with increase in circular frequency. Similar methods can be used to obtain new dynamic spring and damping values for other modes of vibrations such as vertical, rocking and torsional. An analytical treatment of the coupled rocking and sliding modes is presented which considers horizontal and vertical Coulomb friction forces, two-layered soil …
Mechanical Properties Of Cemented Sands Based On Inter-Particle Contact Behavior, Anil Misra, Ching S. Chang
Mechanical Properties Of Cemented Sands Based On Inter-Particle Contact Behavior, Anil Misra, Ching S. Chang
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The mechanical properties of cemented sands are modelled using a micromechanical approach. The derived model accounts for the packing structure, the particle properties and the contact properties.
Modelling The Deformation Of Sand During Cyclic Rotation Of Principal Stress Directions, Marte Gutierrez, Kenji Ishihara, Ikuo Towhata
Modelling The Deformation Of Sand During Cyclic Rotation Of Principal Stress Directions, Marte Gutierrez, Kenji Ishihara, Ikuo Towhata
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The paper presents an elastoplastic constitutive model for the deformation of sand during cyclic rotation of principal stress directions. The model employs a plastic potential theory that allows for the dependency of flow on the stress increment direction and a stress-dilatancy relation incorporating the effects of noncoaxiality. The continuous plastic deformation of sand during principal stress rotation at constant shear stress level is allowed for in the model by using a small elastic area in the stress space. The effects of cyclic stress history is modelled by using discrete surfaces of equal hardening modulus which are allowed to move with …
Presentation Of The Porewater Pressure Buildup Using Moroto's And State Parameter, Predrag Kvasnička, Tomislav Lvšić
Presentation Of The Porewater Pressure Buildup Using Moroto's And State Parameter, Predrag Kvasnička, Tomislav Lvšić
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
In this paper it is attempted to generate the rise of pore water pressures in undrained strain controlled cyclic triaxial tests for various densities (void ratios), confining pressures and strain amplitudes. The results of cyclic triaxial tests on one type of standard Yugoslav sand are presented. Introducing the Moroto's parameter based on cumulative shear work normalized with confining pressure (Moroto, 1976) and a state parameter defined as a distance between initial void ratio and the steady state line (Been and Jefferies, 1985) the band of the results is narrowed and a single curve for representing the pore water pressure buildup …
Soils Parameters And Constitutive Relations Under Multiaxial Cyclic Loading, M. Reza Salami
Soils Parameters And Constitutive Relations Under Multiaxial Cyclic Loading, M. Reza Salami
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
A generalized constitutive model based on the theory of plasticity is proposed and utilized to characterize stress-deformation behavior of soils and geological materials under complex and cyclic multiaxial loadings. It allows for factors such as hardenings, volume changes, stress paths, cohesive and tensile strengths and variation of yield behavior with mean pressure. It is applied to characterize behavior of soils, concrete and rocks. The Constants for the model are determined from series of available laboratory tests conducted under different initial confinements, cyclic hydrostatic preloading and stress paths obtained by using multiaxial and cylindrical triaxial testing devices. The model is verified …
Stiffness And Damping Of Sands In Torsion Shear, Supot Teachavorasinskun, Hiroyuki Kato, Satoru Shibuya, Noriyuki Horii, Fumio Tatsuoka
Stiffness And Damping Of Sands In Torsion Shear, Supot Teachavorasinskun, Hiroyuki Kato, Satoru Shibuya, Noriyuki Horii, Fumio Tatsuoka
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
A laboratory investigation was carried out into stiffness and damping of sands as sheared in a torsional shear apparatus. In the drained monotonic and cyclic loading tests, a particular care was taken of the small strain measurements in which the secant stiffness was measured over a wide range of shear strain from about 10-6 to 10-2. Despite the marked differences in the grain size and the sample preparation method among the sands, a fairly good coincidence of the secant stiffness was seen, in common, in the range of shear strain less than about 1 x 10-5 …
The Dynamic Properties Of Carbonate Sands From Seabed, Du Jian, Wu Xiaofeng, Zhu Longgen
The Dynamic Properties Of Carbonate Sands From Seabed, Du Jian, Wu Xiaofeng, Zhu Longgen
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Four kind of carbonate sands from offshore seabed together with LB sand of U.K and Fujian sand of China were tested with the Resonant Column method. The results show that the stress strain relationship in the condition of small strain can be represented with the hyperbolic model. The modulus is less than that of general sand. The cementing strength between particles of carbonate sands is weak. The breakage of particles is easy after disturbed and the density, therefore, will be increased. These properties should be further studied for engineering purpose.
The Effect Of Frequency Of Cyclic Loading On Earth Structures And Foundation Soils, Daniel E. Normandeau, Thomas F. Zimmie
The Effect Of Frequency Of Cyclic Loading On Earth Structures And Foundation Soils, Daniel E. Normandeau, Thomas F. Zimmie
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Earth dams, earth embankments, slopes, and certain foundation soils are subject to cyclic loading with an initial locked-in static shear stress due to earthquakes, blasting operations, and in some cases machine vibrations. In order to investigate the effect of the frequency of the applied cyclic loading, thirty-one Norwegian Geotechnical Institute Direct Simple Shear (NGI-DSS) tests were run. Frequencies for the applied cyclic loading of 0.2 Hz, 0.05 Hz, and 0.025 Hz were used throughout this investigation. San Fernando Sandy Silt (SFSS), from the Lower San Fernando Dam which failed in 1971, was the material tested in this study. This investigation …
Verification By Comparison Between Static And Dynamic Engineering Soil Parameters Evaluated By Means Of Box Tests, Jan Bencat
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
A conventional track structure system consists of rails, ties, ballast, subballast and subgrade. To design a track on the basis of live load response and permanent settlement, it is necessary to have knowledge of dynamic stresses in the foundation layers of the track. It needs to determine the material properties and thus, the dynamic and permanent deformation response of the track structure. This paper gives results of the experimental measurements of static and dynamic engineering soil parameters evaluated by means of box tests, Bencat 1989.
An Approach To Characterise Cyclic Deflection Of Piles In Calcareous Soil Media Under Offshore Wave Loading Conditions, Y. S. Golait
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.
An Innovative Dynamic Test Method For Piles, M. C. Janes, R. C. Horvath, P. D. Bermingham
An Innovative Dynamic Test Method For Piles, M. C. Janes, R. C. Horvath, P. D. Bermingham
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The system described involves using solid propellant fuels to accelerate a reaction mass of the test pile. The force required to accelerate the reaction mass upwards acts equally downward on the pile. Very high forces be may applied to the pile in a controlled, linearly increasing manner. The duration of the applied load is approximately 100 milliseconds. This rate of loading is slow enough to allow the pile and soil to react together as a composite rigid body. The effects combine to produce pile and soil response no longer dominated by the transfer of force via stress pulse (as with …
Centrifugal Modeling Of A Pile Under Vertical Random Excitation, Lary R. Lenke, Hon-Kim Ko, Ronald Y. S. Pak
Centrifugal Modeling Of A Pile Under Vertical Random Excitation, Lary R. Lenke, Hon-Kim Ko, Ronald Y. S. Pak
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Data from the experimental modeling of a pile in a geotechnical centrifuge are compared with analytical results. The model pile was subjected to vertical random excitation with subsequent determination of the compliance function in the frequency domain. This compliance function was found to be consistent with theory. An absorbing boundary was used to minimize reflected wave energy from the centrifuge container boundaries.
Session 2: Closing Remarks, C. K. Shen
Session 2: Closing Remarks, C. K. Shen
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
No abstract provided.
Deformation Of Reconstituted Clay Under Cyclic Loading, S. W. Yan, D. J. Williams
Deformation Of Reconstituted Clay Under Cyclic Loading, S. W. Yan, D. J. Williams
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Reconstituted soft clay triaxial specimens were prepared by means of vacuum preloading. Both static and cyclic tests were carried out, with the specimens consolidated under different principal effective stress ratios. The test results lend themselves to incorporation in a finite element formulation, which can readily be used for calculating the deformation of soft clay under cyclic loading.
Session 2: Discussions And Replies, Multiple Authors
Session 2: Discussions And Replies, Multiple Authors
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
No abstract provided.
Large-Scale Model Forced-Vibration Test Comparison Of Test Results On Hard And Soft Ground, Takeshi Fujimori, Tomohiko Tsunoda, Kinji Akino, Masanori Izumi
Large-Scale Model Forced-Vibration Test Comparison Of Test Results On Hard And Soft Ground, Takeshi Fujimori, Tomohiko Tsunoda, Kinji Akino, Masanori Izumi
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Forced-Vibration tests were performed on two large-scale same models constructed on soft and hard ground in order to investigate the effect of the hardness and the stratification of the supporting ground on the vibration characteristics of simulated reactor buildings. The soft ground is almost stratification ground, and the hard ground is almost uniform ground. The test models are RC rigid frame structure with shear walls. In the tests, sinusoidal wave excitation was applied by the excitor. The vibration characteristics of the test models, earth pressure at the bottom of the base mat and the vibration characteristics of the surrounding ground …
Measured Full-Scale Dynamic Lateral Pile Responses In Clay And In Sand, Matti Hakulinen
Measured Full-Scale Dynamic Lateral Pile Responses In Clay And In Sand, Matti Hakulinen
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
In order to design machine foundations and to examine interaction between pile and soil, versatile horizontal dynamic loading tests were done to piles. In the tests both stiffness and damping values of piles were measured in overconsolidated clay and in earthfill sand. The stiffness of piles was analyzed by Winkler's spring method and the damping of piles with Gazetas' and Dobry's method. The measured and calculated values were almost the same when stiffness was considered. In damping the measured values were about 40 ... 70% of the calculated values. Very important in the calculation is to know which is the …
General Report Session 2: Model Testing In Cyclic Loading, Mladen Vucetic
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 …