Engineering Commons^™

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 …

Earthquake Damages Influenced By Soil Conditions In Historical Buildings In Istanbul, Nafiz Çamlibel

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

This paper is based on the study of the damages by earthquakes on the historical buildings constructed in Bysantine and Ottoman period and represents a preliminary approach to the problem of identifying the causes of these damages influenced by soil conditions. In this paper, some aspects of soil conditions and foundations systems are given related to the preservation of monument, especially the presentation is concentrated on the following topics: • An estimation of seismic area and on Design basis response spectra for historical buildings. • Geotechnical problems of the old city Istanbul. • Statistical aspects of masonry of Bysantine and …

Lateral Stiffness And Damping Coefficient Of Soils For Seismic Analysis Of Buried Pipelines, Xinjian Zhang, Leon R. L. Wang, Isao Ishibashi

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

The stiffness and damping coefficient of soil are critical parameters in the Winkler's model for the seismic analysis of buried pipelines. This paper presents an analytical study in calculating the lateral dynamic stiffness (elastic and inelastic) and damping coefficient of soils for the seismic analysis of buried pipelines. The effects of the depth of the buried pipeline and the variation of Poisson's ratio of soils are cons1dered. In the analysts, first, by using the elastic half-space theory, the elastic stiffness and geometrical damping coefficient of soils are obtained. From the numerical results, the elastic stiffness and geometrical damping coefficient by …

Pile Foundation Harmonic Vibration Determined By Wave Difraction On Piles, V. Llyichev, A. Shlyakis

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

The problems of the low pile foundation vibrations, dynamic loads affecting it together with the horizontal and vertical harmonic forces as well as the wave effect presented by the sum of the elementary harmonics for plane, longitudinal and transversal, horizontally and vertically polarized waves.

Seismic Response Of Axially Loaded Pile Group, Takaaki Kagawa

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

This paper presents a numerically efficient procedure for evaluating seismic responses of an axially loaded pile group. This procedure was used to clarify the impact on pile-group responses of employing different levels of soil-pile compatibility conditions. This study clearly demonstrated that the limitations and shortcomings of adapting relaxed soil-pile compatibility conditions are not negligible for pile groups with relatively small spacing ratios and with soil stiffnesses constant or decreasing with depth.

The Soil-Structure Interaction In Bridge Dynamics Problems, E. V. Berezantseva, A. M. Uzdin, Yu. G. Kozmin

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

At the Bridges Department of Leningrad Institute of Railway Communication Engineers complex investigations of bridge dynamics under the seismic and rolling stock loads had been carried out. It is ascertained that for theoretical description of bridge oscillations the question of "piers-base" interaction is a matter of principal importance. During the process of oscillations there is a loss of energy due to the radiation by the propagation of elastic waves in the soil. These losses of energy considerably exceed the hysteresis ones, especially for bridges with metal span structures. Researches carried out allowed to make the theoretical estimation of the general …

Soil Dynamics In The Offshore, Vijay K. Puri, Shamsher Prakash

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

Offshore structures are subjected to the action of wind, wave, sea storms, and earthquakes, and transmit dynamic loads to the underlying soils. This paper highlights the role of soil dynamics in the design of foundations for offshore structures. The motion characteristics associated with storm waves and earthquake loading are discussed. The necessity to consider earthquake load in addition to the environmental loads depending on the location of the offshore structure is discussed. The paper also presents the results of dynamic test on a single pile and a comparison of the observed and predicted response of the Pile.

Session 7: Concluding Remarks, Panos Dakoulas

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

No abstract provided.

Nonstationary Stochastic Seismic Response Analysis For Earth And Rockfill Dams, Wu Zaiguang, Lin Gao, Han Guocheng

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

In this article, the time domain madal analysis technique for evaluating the nonstationary responses of linear systems is combined with the equivalent linearization approach for determining the stationary responses of nonlinear soil structures. A new analysis method is formed and the nonstationary responses of the earth and rockfill dam are calculated. The results from nonstationary analysis are compared with the ones from the stationary computations. The effectiveness of nonstationarity of input and output is investigated and the relevant conclusions are given.

Permanent Deformation Of Earth Dam Due To Earthquake, Jia-Huan Qian, Zhen-Son Hong, Li-Zhen Zeng

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

This paper combines the equivalent nodal force method suggested by serf et al, (1976) and equivalent inertial force method proposed by Taniguchi et al (1983, 1987). The former is fine to utilize seed's strain potential but the stress-strain curve is obtained only by static test, while the latter uses dynamic stress-strain curve, but the determination of direction of equivalent inertial force is rather difficult. The writers use the equivalent nodal force by average shear stress (τ_{av=0.65 τmax) and assume it's direction to be coincided with static shear stress. Also dynamic stress-residual shear strain curve is obtained by …}

General Report Session 7: Stability Of Slopes And Earth Dams Under Earthquakes, J. Lawrence Von Thun

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

The papers received for this session may be classified into five general topic areas; the number of papers in each subtopic area is shown in parentheses.

1. Slope stability analysis incorporating dynamic loading Ÿanalysis methods (3)

Ÿdynamic effects on soil properties (2)

Ÿcase study (1)

2. Dynamic response of embankment dams

Ÿanalysis methods (5)

Ÿcase studies (2)

3. Dynamic deformation analysis

Ÿanalysis methods adapted for a specific case (3)

Ÿcomparison of analysis methods (1)

4. Dynamic deformation or stability analysis incorporating pore pressure development or liquefaction considerations Ÿanalysis methods (3)

Ÿanalysis methods developed for a specific case (2)

Ÿcase history …

The Study Of Xintan Landslide's Sterescopic Monitoring In The Changjiang River Three Gorges, Zhu Ruigeng, Lu Wenxing, Kia Yuanyou

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

This paper emphatically introduces a new landslide’s stereoscopic monitoring system that was builded in Xintan slope after failed. The movement in the underground different level can be decided through monitoring of surface by the system. The system can provide a basis to master the slope gliding regulartion so that a new prediction method may be worked out in the future.

Attenuation Characteristics Of Ground Strains Induced During Earthquake, Ken-Ichi Tokida, Koh Aizawa, Keiichi Tamura

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

The appropriate estimation of ground strains Induced during earthquake is indispensable for the seismic design of buried lifeline facilities such as pipeline systems. The ground strains induced during earthquakes are calculated with use of the dense instrument array data observed during past 78 earthquakes for the surface ground at the Public Works Research Institute (PWRl) ln Tsukuba Science City in Japan. Based on the multiple regression analysis for the calculated ground strains, the empirical formulae of attenuation of maximum ground strains for such the ground condition as the PWRI campus are proposed ln terms of earthquake magnitude and epicentral distance, …

Session 9: Closing Remarks, Ken-Ichi Tokida

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

No abstract provided.

Seismic Zonation Of India, L. S. Srivastava, S. Basu

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

The Himalayan belt, Indo-Gangetic Plains and Peninsular shield divide India in three major regions with decreasing seismic potential. The Indian Standard Criteria for Earthquake Resistant Design of Structures (IS: 1893-19841) incorporate a seismic zoning map (SZM) demarcating five seismic zones, which show zones with many islands, and prescribed design parameters for the delineated zones do not show consistent exceedance probability. A probabilistic analysis has been carried out and seismic design ground motion parameters have been estimated for 100 years’ service life, which do not support delineation of five zones with uniform ratio of seismic hazard among various zones. Four seismic …