Engineering Commons^™

Field And Laboratory Determination Of Soil Properties At Low And High Strains, R. D. Woods

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

Over the past quarter century many testing methods have been used to determine soil properties for dynamic analysis. Most methods had been established by the time of the writer's review (Woods, 1978), and since then, changes have been mostly evolutionary. Many field and laboratory techniques are represented in papers submitted to this conference and these are reviewed, but additional citations from literature in the intervening years has been included for completeness. No claim is made that all pertinent literature is included, but that most methods of field and laboratory testing methods are covered with representative citations.

Flow Failure Of Liquefied Sand In Large-Scale Shaking Tables, Kenji Ishihara, Mikio Takeuchi

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

Laboratory studies on flow failure in liquefied sand deposits using large-scale shaking tables are briefly introduced, together with a case study on the lateral deformation in the field. The key parameters influencing the occurrence of flow-type deformation are discussed in an effort to figure out a mechanism or scenario of the flow failure. In one series of the laboratory studies, shaking table tests were performed to examine the effectiveness of a preventive measure against the flow slide. This aspect is also discussed briefly.

Piles Under Dynamic Loads, M. Novak

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

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

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

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

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

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

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

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

Fault Processes And Liquefaction In The Marine Environment, Ronald C. Chaney

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

No abstract provided.

Panel Reports: Discussions, Multiple Authors

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

No abstract provided.

Soil-Pile Interaction Model For Earthquake Response Analysis Of Offshore Pile Foundations, Toyoaki Nogami

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

No abstract provided.

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

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

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

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

No abstract provided.

Table Of Contents, Multiple Authors

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

No abstract provided.

An Estimation Of Dynamic Properties Of Soils From Block Vibration Tests, V. D. Miglani

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

The paper presents departures that have to be made in the conduct of block vibration tests from the standard method and in the analysis of test data under unusual conditions. Disturbed soil condition under an edge of the block leads to occurrence of double peaks in amplitude versus frequency curves from vertical vibration test. Two methods have been devised to analyze such double peaks. The first method assumes a correlation between dynamic coefficients. The dynamic properties can be predicted from non-dimensional curves of correction factor versus ratio of effective base area. The second method assumes linear variation of coefficient of …

Behavior Of A Geosynthetic Reinforced Sand, H. C. Liu, N. Y. Chang

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

The method of geosynthetic reinforced earth incorporates a flexible but tension resistant synthetic material in soil to increase the tensile resistance of the composite. In this study, both static and dynamic responses of an Ottawa 30-40 sand reinforced with a nonwoven geosynthet1c, Bidim C-34, were investigated. Static triaxial tests were first conducted to examine the influence of the reinforcement on strength, Young's modulus, and Poisson's ratio of the composite soil. Cyclic triaxial tests and resonant column tests were then conducted to examine the variation of shear modulus and damping ratio at different strain amplitudes. The influence of geosynthetic on both …

Session 1: Closing Remarks, M. Pastor

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

No abstract provided.

Energy-Absorbing Ability Of Texsol, Phong M. Luong

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

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

GMax From Pressuremeter Tests: Theory; Chamber Tests; And Field Measurements, Peter M. Byrne, Francisco Salgado, J. A. Howie

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

A method of analysis to predict the in situ maximum shear modulus G_max,0 from self-boring pressuremeter unload tests is presented. The method considers both the stress and void ratio changes induced by pressuremeter loading and the nonlinear stress-strain response upon unloading. The results are presented in the form of a chart that allows G_max,0 to be determined from the equivalent elastic unload modulus, G*, for a wide range of loading and unloading conditions. The analysis procedure is checked with chamber tests and field data and the results are found to be in good agreement provided factors to account …

Modeling The Monotonic And Cyclic Viscoplastic Soil Behavior, Ronaldo I. Borja

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

We describe a class of viscoplastic constitutive models capable of simulating the monotonic and cyclic rate-dependent soil behavior. These models are developed by enriching their inviscid counterparts with a viscous character to model the irreversible deformation that develops with time. The viscoplastic strain rate is of the Duvaut-Lions type whose magnitude increases with the distance of the stress point from its projection onto the inviscid solution. With appropriate choice of an inviscid elasto-plastic soil model, one can generate quasipreconsolidation effects during creep and account for the influence of frequency on the shape and width of hysteresis loops formed during cyclic …

General Report Session 1: Static And Dynamic Soil Parameters And Constitutive Relations Of Soils, Peter M. Byrne, Li Yan

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

The soil parameters that are commonly of interest in dealing with earthquake and soil dynamics problems are:

1) The maximum shear modulus G₀, or the shear wave velocity, V_s.

2) The variation of secant shear modulus with shear strain level, G/G₀ vs γ.

3) Equivalent viscous damping as a function of strain.

4) Other parameters such as, dilatometer modulus, normalized SPT or CPT value, state parameters, formation factor.

In terms of constitutive relations the following models have been used:

1) Linear elastic (total stress) - appropriate at very small strains < 10^-3%.

2) Equivalent linear …

Stiffness And Damping Parameters For Dynamic Analysis Of Retaining Walls, E. Arni Rafnsson, Shamsher Prakash

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

The displacements of retaining walls developed during earthquakes have been recognized for many years. Mathematical models have been developed to simulate the behavior of retaining walls during earthquakes. The determination of the soil parameters needed for solution of the displacements has neither been adequately described nor used in a realistic analysis. In this paper theories describing spring and damping constants of rigid retaining walls, for both the base-soil and the back-fill, arc discussed along with the recommended solutions.

Laboratory Tests On Embedded Reactor Building On Soft Ground, Ltaru Kurosawa, Shohara Ryoichi, Kinji Akino, Masanori Izumi

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

Model tests using shaking table and impulse hummer were performed to confirm analysis tools currently used in Japan for the seismic design of a reactor building embedded in soft ground. The models are made of a silicone rubber ground and an aluminum building. Embedment depths of the foundation are varied. Comparison between test results and analytical results is discussed in terms of impedance functions, foundation input motions and structure responses.

Liquefaction Tests By A Laminar Box In A Centrifuge, Kichio Suzuki, Ryouichi Babasaki, Yoshio Suzuki

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

A new laminar box constructed with aluminum frames of 24mm wide and 10mm thick for model shaking tests on liquefaction phenomenon of soft saturated sandy soil in centrifugal gravity field was manufactured. The box was designed to develop shear distortion in the soil unimpeded by a rigid-type container. Liquefaction tests were performed on horizontally laid soft saturated sand and obtained the same results as Tokimatsu and Yoshimi 1983.

A Practical Assessment Of Site Liquefaction Effects And Remediation Needs, Geoffrey R. Martin, Kandiah Arulmoli, Chan-Feng Tsai

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

This paper describes a case history where potential earthquake induced liquefaction is of concern at a site where a major housing development is planned. The site comprises inter-layer saturated loose to medium dense sandy silts, silty sands and soft clay layers to a depth of 35 ft. Liquefaction potential at the site was evaluated through the use of cone penetrometer test (CPT) logs and standard penetration test (SPT) data. Results of DESRA-2 effective stress site response analyses were also used to determine pore pressure response at the site for a given design earthquake, and are compared to liquefaction assessments conducted …

An Energy Approach In Defining Soil Liquefaction, J. Ludwig Figueroa, Nitin Dahisaria

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

The concept of energy to define liquefaction has been recognized by several authors. This approach has the advantage over other known methods to define liquefaction of considering a fundamental concept (energy), and of offering the potential of more closely considering random motion effects such as those introduced by earthquake loading. This paper presents the development of relationships between normalized pore pressure and unit energy required to induce liquefaction from testing hollow cylinder sand specimens prepared at different relative densities, and subjected to different confining pressures and shear strain amplitudes. Specimens were tested under constant maximum strain using a sinusoidal torsional …

Applicability Of Effective Stress Analysis For The Soil-Structure System In Design Practice, Shunji Fujii

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

In the design process of a high rise building in Niigata City, the prediction of liquefaction potential has been conducted by comparing liquefaction resistance obtained from laboratory tests, with shear stress obtained in a total stress analysis of a soil-structure model. As an attempt, one dimensional and two dimensional effective stress analysis were carried out by using a computer program DIANA. By the comparison of these analytical results, the applicability of the effective stress analysis to the actual soil-structure system has been examined.

Liquefaction Analysis By Multi-Surface Model, Satoshi Morio

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

In recent years, liquefaction phenomena induced by earthquakes have attracted considerable attention and extensive research has already been performed on various aspects. Also, many constitutive relations have been proposed in order to represent the deformation behavior during cyclic loading. These models, however, have mostly been verified by comparison stress or strain control element tests, and there have not been many numerical tests applying them to the boundary value problems. In this study, a simple and practical constitutive relation which is able to simulate the unelastic behavior of soils under multi-directional cyclic stresses is proposed. The proposed model has been introduced …

Slides Of River Banks Concerning Lateral Spread Of Liquefaction, Huishan Liu, Chengchuen Wang, Lunian Wong

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

In this paper 19 cases of river bank slides concerning lateral spread of liquefaction are summarized, some of them are discussed in detail. One of the cases was the lateral spread of liquefied sands by Liao River during Heichen Earthquake (1975, M=7.3). The width of sliding zone in direction perpendicular to the flow was around 500-600m. The second case was about an industrial area in Tianjing, one of the largest cities in China. The land sliding along a silted old course made many buildings cracked and even collapsed. The third case was on liquefaction along Dou River and Luan River. …

Some Key Problems In Calculating Seismic Pore Water Pressure, Zhang Jianmin, Xie Dingyi

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

The problems of selecting a reasonable generation model and a reasonable generation-dissipation model of pore water pressure and determining the coefficient of permeability and the coefficient of volumetric strain in the course of pore water pressure generation-dissipation are crucial in the calculation of seismic pore water pressure. These problems are investigated theoretically and experimentally in this paper based on the concepts of transient pore pressure with connection to the practically possible calculating conditions, so as to improve the reliability of the current seismic effective stress analysing method.

General Report Session 4: Dynamic Earth Pressures And Seismic Design Of Earth Retaining Structures, R. Richards Jr.

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

The great number of significant variables which effect the seismic behavior of retaining structures make this both a fascinating subject and a difficult one. The ten papers in this session cover both elastic and plastic aspects of analysis and design for a wide variety of wall types. To help put them in perspective, a new, fundamental seismic free-field solution will be reviewed briefly. This will serve as a benchmark from which the effects of changing the lateral boundary condition by introducing various types of walls can then be evaluated.

Anti-Seismic Reinforcement Of Pipelines In A Liquefied Ground, Takashi Akiyoshi, Kunihiko Fuchida

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

An anti-seismic structural-reinforcemental method for buried pipelines is presented and analytically investigated on the effectiveness for lateral flow of liquefied grounds during earthquakes. The proposed method of the reinforcement is to fix main pipelines with expansion joints to parallel auxiliary continuous pipes using iron-plates. Stiffness of liquefied soils is around pipes is represented as a coefficient of subgrade reaction between liquefied sand deposits and pipes, based on the experimental results. Analysis of the pipeline-soil spring systems is conducted using the modified transfer matrix method. Computations are performed with respect to the displacement, strain, stress, and rotational angle of joint of …

Deformation Of Soil To Seismic Waves Reflected On Foundation, L. R. Stavnitser

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

Interacting with constractions foundations during earthquake elastic seismic waves form reflected waves field which interference with coming waves lead to an increase of stresses near by foundation. These stresses can exceed the earth limit of elasticity and become the reason of limited plastic deformations region formation and residual foundations seismosettlements. In order to describe this phenomenon solution of the problem of non-standard elastic wave interaction with shifting base of foundation is obtained for conditions of caused by interference reflected plastic wave generation behind the front of which medium load relief takes place which can be described using bilinear elastic-plastic model …