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2001

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Articles 931 - 960 of 1795

Full-Text Articles in Engineering

Numerical Study On 3-Dimensional Behavior Of A Damaged Pile Foundation During The 1995 Hyogo-Ken Nanbu Earthquake, Ryosuke Uzuoka, Tetsuo Kubo, Atsushi Yashima, Feng Zhang Mar 2001

Numerical Study On 3-Dimensional Behavior Of A Damaged Pile Foundation During The 1995 Hyogo-Ken Nanbu Earthquake, Ryosuke Uzuoka, Tetsuo Kubo, Atsushi Yashima, Feng Zhang

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

The purpose of this study is to investigate the process of the damage to a pile foundation located on a reclaimed land during the 1995 Hyogo-ken Nanbu earthquake. A 3-dimensional effective stress analysis using a soil-pile-building model was conducted on a damaged building. The five stories building tilted in a northeast direction because of serious damages to the pile foundations. Sand boils and ground settlements due to liquefaction were observed around the building. The simulated results showed that the reclaimed fill layer liquefied during the earthquake, and horizontal displacements of several tens centimeters occurred at the ground surface. The spatial …

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Soil-Pile Interaction Analysis Using Fe-Be Coupling In Frequency Domain, Moon Kyum Kim, Yun Mook Lim, Min Kyu Kim, Seok Ho Cho Mar 2001

Soil-Pile Interaction Analysis Using Fe-Be Coupling In Frequency Domain, Moon Kyum Kim, Yun Mook Lim, Min Kyu Kim, Seok Ho Cho

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

In this study, a numerical method for soil-pile interaction problems in multi-layered half-plane is developed in frequency domain using FE-BE coupling technique. The soil-pile interaction system is divided into two parts, so-called near field and far field. In the near field, beam elements are used for modeling pile and plane-strain finite elements for surrounding soil media. Also, a superstructure is considered as a lumped mass on a pile. In the far field, layered soil media is modeled by boundary element formulation using the dynamic fundamental solution. Then, these two fields are assembled using FE-BE coupling technique. This coupled numerical method …

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Effect Of The Non-Linear Behavior Of Pile Material On The Response Of Laterally Loaded Piles, Mohamed Ashour, Gary Norris, Anooshirvan Shamsabadi Mar 2001

Effect Of The Non-Linear Behavior Of Pile Material On The Response Of Laterally Loaded Piles, Mohamed Ashour, Gary Norris, Anooshirvan Shamsabadi

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

The main purpose of this study is to assess the lateral response of piles/shafts and the p-y curves for different soil-pile combinations while introducing the effect of the moment-curvature (M - Φ) relationship of the pile into the soil-pile interaction. Therefore, the equilibrium among soil reaction, pile deflection pattern, pile-head load, and flexural stiffness distribution should be satisfied at any level of loading. The influence of the nonlinear behavior of the pile/drilled shaft material on the nature of the associated p-y curve is presented through strain wedge (SW) model analysis. The SW model allows the assessment of the (soil-pile) modulus …

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Granular Material Behaviour Under Dynamic Excitation, Rocco Wagner, Konstantin Meskouris Mar 2001

Granular Material Behaviour Under Dynamic Excitation, Rocco Wagner, Konstantin Meskouris

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

This paper deals with the investigation of bulk material filled silos under seismic excitation. The described numerical model for a silo consists of three components, namely the granular material, an interface element between the granular material and the silo wall and the silo itself. The bulk material behaviour is described in four different ways: by the classical hypoplasticity theory, by two special versions of it which use time history functions and finally by the intergranular strain approach. The dynamic behaviour as described by these four different material laws is presented, as well as comparisons of the numerical results with experimental …

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Lateral Flow Deformation Evaluation Of Ground-Structure System Under Various Cyclic Loading Conditions, Masahiro Miyaura, Seiichi Miura, Shima Kawamura, Shoji Yokohama Mar 2001

Lateral Flow Deformation Evaluation Of Ground-Structure System Under Various Cyclic Loading Conditions, Masahiro Miyaura, Seiichi Miura, Shima Kawamura, Shoji Yokohama

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

In order to clarify the mechanical behaviors of sand grounds induced by various loadings including sea wave forces, traffic vibrations and earthquake etc., a series of model tests were carried out on model structure-ground system by using, the two-dimensional plane strain soil box apparatus. It was found that; (1) the lateral flow behavior of ground depends strongly on settlement performance of a structure, (2) the bearing capacity of ground may be evaluated by a failure envelope which is depicted in M-V-H plane irrespective of the difference in loading conditions and (3) the stability of sand ground-structure system can be assessed …

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Foundation-Soil-Inclusion Interaction Modelling For Rion-Antirion Bridge Seismic Analysis, Dan Yang, Ricardo Dobry, Ralph B. Peck Mar 2001

Foundation-Soil-Inclusion Interaction Modelling For Rion-Antirion Bridge Seismic Analysis, Dan Yang, Ricardo Dobry, Ralph B. Peck

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

The Rion-Antirion Bridge in Greece will span a total length of 352 1 m, which includes a five span cable-stayed bridge 2252m in length and two approach viaducts. Upon completion in 2004, the bridge will be the longest cable-stayed bridge in the world. The main factors affecting the foundation design involve high seismicity, poor in-situ soil conditions, deep sea water (65m) and high ship impact force. These factors called for an innovative foundation design for each of the 90m diameter piers by the foundation designer, Geodynamique et Structure (GDS) from France. The proposed design consists of vertical open-ended steel cylinders …

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Prediction Of Lateral Dynamic Response Of Single Piles Embedded In Fine Soils, Shamsher Prakash, Houda Jadi Mar 2001

Prediction Of Lateral Dynamic Response Of Single Piles Embedded In Fine Soils, Shamsher Prakash, Houda Jadi

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

The lateral dynamic response of a single pile predicted by analytical models often yields higher natural frequencies and lower resonant amplitudes than those determined in field tests. This has been related to overestimated soil’s shear modulus and radiation damping used in the calculations of the response. The objective of this study was to determine a simple method to improve the theoretical predictions, primarily those of piles embedded in clay or fine silty sands. Accordingly, reduction factors to the soil’s shear modulus and radiation damping were proposed. These factors were related to the shear strain at predicted peak amplitudes.

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Seismic Risk And Site Response Analysis For City Of Bandung-Indonesia, I. Wayan Sengara, Yulman Munaf, Aswandi, I Gede Mahardika Susila Mar 2001

Seismic Risk And Site Response Analysis For City Of Bandung-Indonesia, I. Wayan Sengara, Yulman Munaf, Aswandi, I Gede Mahardika Susila

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

Bandung is considered as a relatively earthquake prone region. Seismic risk analysis considering subduction zone and surrounding active strike-slip faults in the area was performed. Crouse and Joyner & Boore attenuation functions were adopted for the subduction and strike-slip faults, respectively. The analysis was performed employing total probability theorem using EQRISK program with modification on the attenuation functions. The analysis indicated that peak base-rock acceleration is 147 gal and 200 gal for 200 and 500 years return period, respectively. Local site effects were considered by performing site response analyses in the form of wave propagation analysis from base-rock to ground …

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Geotechnical Data Base For The City Of Zagreb And Its Application In Site Response Analyses, Predrag Kvasnička, Leo Matešić Mar 2001

Geotechnical Data Base For The City Of Zagreb And Its Application In Site Response Analyses, Predrag Kvasnička, Leo Matešić

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

Geotechnical reports, filed in the city archives, are the source of data among which relevant properties for mechanical soil behavior and site response analyses are recognized and digitised. The properties are digitised in an organized manner into the GIS related software called “Techbase”, developed by “MINEsoft“, Lakewood, Colorado. The basic element of the database is a boring log containing distributions of soil properties with depth. More than 150 boring logs, located in the western part of Zagreb, are digitized and their coordinates mapped using “Techbase”. The aim of this paper is not only to describe the collection of the geotechnical …

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Study On Seismic Retrofit Planning Method For Seweage Treatment Plants On The Basis Of Seismic Risk Management, Akira Yuasa, Tsuneo Ohsumi, Kenichi Yamamoto, Tetsutaro Kawakami Mar 2001

Study On Seismic Retrofit Planning Method For Seweage Treatment Plants On The Basis Of Seismic Risk Management, Akira Yuasa, Tsuneo Ohsumi, Kenichi Yamamoto, Tetsutaro Kawakami

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

Japanese sewerage has more than 100 years of history, and many facilities have passed their durable years. For the sake of economy, life lengthening of the equipment and facilities is required. Rational life extension of the equipment and facilities calls for aseismic reinforcement of structures with damage risks considered. Based on this, the author et al. suggested a method that will help planning rational aseismic reinforcement for sewage treatment plants. This method quantitatively evaluates the relationship between the earthquake risk and aseismic reinforcement cost by introducing the concept of risk management. In this study, availability of this method also has …

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Site Response Of Organic Soils, Rajendram Arulnathan, R. W. Boulanger, I. M. Idriss Mar 2001

Site Response Of Organic Soils, Rajendram Arulnathan, R. W. Boulanger, I. M. Idriss

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

A primary source of uncertainty in any evaluation of the seismic stability of the Sacramento-San Joaquin Delta levee system is the site response characteristics of the shallow organic soils that commonly underlay the levees. This paper provides an overview of recent research on the site response characteristics of organic soils using centrifuge and numerical modeling. The centrifuge modeling effort included the development of techniques to measure the shear wave velocity profile for a centrifuge model while in-flight. One-dimensional site response analyses using an equivalent linear procedure were performed with the measured shear wave velocity profiles and the modulus reduction and …

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Global Methodology For Soil Behavior Identification And Its Application To The Study Of Site Effects, A. Modaressi, F. López-Caballero Mar 2001

Global Methodology For Soil Behavior Identification And Its Application To The Study Of Site Effects, A. Modaressi, F. López-Caballero

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

Though it is now admitted that non-linear modeling of soil behavior is necessary to represent some important aspects of the soil response under strong ground motion (for example, irreversible settlements and pore-pressure build-up), the elastoplastic models are not yet used in the everyday design processes. One of the obstacles is the difficulty to identify the models’ parameters. A methodology to identify the soil mechanical parameters is presented and applied to an elastoplastic model. The strategy is based on the use of minimum physical and easily measurable parameters. The key parameter necessary for characterizing the clay is its Liquidity Limit, while …

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Dynamic Youngis Modulus And Axial Strain Relationships, X. J. Zhang, M. S. Aggour Mar 2001

Dynamic Youngis Modulus And Axial Strain Relationships, X. J. Zhang, M. S. Aggour

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

Equations of Young’s moduli of sands as a function of the axial strain amplitude for different types of dynamic loading were developed from a series of resonant column tests. Ottawa 20-30 sand specimens were excited longitudinally with one of three types of loading at three different confining pressures. In the sinusoidal tests, excitation signals were generated by a variable frequency sine-wave oscillator. In the random tests, input signals were generated by a white-noise generator and a pulse signal generator was used in the impulse tests. Input and output signals were analyzed by an FFT analyzer in the random and impulse …

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An Approach To Predict Shear Modulus Of Soils In The Range Of 10-6 To 10-2 Strain Levels, António Gomes Correia, Jaime Santos, José Maria C. Barros, Sussumu Niyama Mar 2001

An Approach To Predict Shear Modulus Of Soils In The Range Of 10-6 To 10-2 Strain Levels, António Gomes Correia, Jaime Santos, José Maria C. Barros, Sussumu Niyama

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

This paper presents the results of several resonant column tests carried out in a large variety of soils, including lateritic and saprolitic tropical soils. The data analysed are restricted to the strain dependence of shear modulus in the range of 10-6 to 10-2. Despite the different isotropic consolidated stresses, degrees of saturation and overconsolidation ratios applied for the different types of soil, all the test results fit very well in a previous proposed normalised curve of G/G0 as a function of γ/γ0.7, where γ0.7 is the shear strain corresponding to a value of …

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Influence Of Compaction And Loading Conditions Of The Dynamic Properties Of A Silty Sand, Jean-Marie Fleureau, Emmanuel Dufour-Laridan, Antônio Gomes Correia Mar 2001

Influence Of Compaction And Loading Conditions Of The Dynamic Properties Of A Silty Sand, Jean-Marie Fleureau, Emmanuel Dufour-Laridan, Antônio Gomes Correia

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

Elastic properties of a compacted silty sand were measured in a precision triaxial cell at the École Centrale de Paris in the range of very small strains (between 10-6 and 10-4), using improved Hall effect-based local strain gauges and data acquisition system. The dynamic properties of the soil were also derived from resonant column tests at the IST, in Lisbon, as functions of shear strain, compaction water content and confining pressure. Elastic limits as low as 5.10-6 were found in both devices, with Poisson’s ratio from triaxial tests ranging from 0.05 at very strains (< 10-4 …

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Dynamic Behavior Of Tropical Soils From Medllin, Colombia, Manuel R. Villarraga Mar 2001

Dynamic Behavior Of Tropical Soils From Medllin, Colombia, Manuel R. Villarraga

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

Medellin City has a population of about 2,000,000 people and its area is lower than 110 km2. This city is located in the northwest of Colombia, that is in the northwest corner of South America, which is a zone with a complex tectonic environment associated to the interaction of the Naza, Suramerica and Caribe plates. The result of these conditions implies that Medellin has an intermediate seismic hazard. This city was developed on tie valley of Medellin River and his slopes, has a complex geology, which is composed by alluviums, colluviums of different ages, residual soils from igneous …

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Measurement Of Dynamic Properties Of Clay Using The Downhole Freestanding Shear Device, Michael F. Riemer, Carlton Grizzle, Osama Safaqah Mar 2001

Measurement Of Dynamic Properties Of Clay Using The Downhole Freestanding Shear Device, Michael F. Riemer, Carlton Grizzle, Osama Safaqah

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

The Downhole Freestanding Shear Device is a new, in situ tool for measuring the dynamic properties of cohesive soil deposits. It has been designed and developed to perform cyclic torsional shear tests on freestanding specimens beneath the bottom of a cased borehole, with the goal of measuring local strains on soil which has not been significantly disturbed by the drilling, sampling, or unloading/reloading processes associated with conventional laboratory testing. The research team has completed the device, and is now in the process of validating its performance, first in a laboratory setting. The current paper presents results from the initial tests …

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A Study Of Soil Microstructure Using Bender Element Tests, J. Abraham Díaz-Rodríguez, Pedro Moreno-Carrizales, Luis López-Flores Mar 2001

A Study Of Soil Microstructure Using Bender Element Tests, J. Abraham Díaz-Rodríguez, Pedro Moreno-Carrizales, Luis López-Flores

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

An application of bender elements to measure the effect of soil microstructure in shear wave velocity is presented. A testing program was carried out on Mexico City sediments using a triaxial cell fitted with bender elements. Shear wave velocities were measured during isotropic consolidation and during failure. From the results of these tests simple expressions were obtained which describe the variations of shear wave velocity with the current state in terms of the effective stress and axial deformation.

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Degradation Characteristics Of Clay-Shale Samples Under Cyclic Loading, M. Zoghi Mar 2001

Degradation Characteristics Of Clay-Shale Samples Under Cyclic Loading, M. Zoghi

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

It is known that reduction and degradation of soil strength and stiffness during cyclic loading typically result in damage to structural foundations and earth structures due to excessive settlement and tilting and may cause slope instability and embankment failure. Case histories, representing damages during earthquakes, due to this phenomenon are numerous. It is the guiding principle of this paper to present an overview of degradation characteristics of combined clay-shale samples under cyclic loading and describe how this phenomenon can be utilized in evaluating the seismic stability of slopes involving colluvium.

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Infrared Thermography Of Dissipation In Soil, Minh-Phong Luong Mar 2001

Infrared Thermography Of Dissipation In Soil, Minh-Phong Luong

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

The paper introduces infrared thermography as a noncontact and non-destructive technique that conveniently offers the possibility of evaluating the energy-dissipating ability of soil, traditionally difficult to be determined using traditional techniques. It allows records and observations in real time of heat patterns produced by the dissipation of energy caused by friction between grains. Such dissipative heat occurs when soil is subjected to vibratory loading exceeding the characteristic threshold, and it evidences the distortion mechanism. This energy dissipation mechanism influences the wave speed, intergranular attenuation, and dispersion through particles contacts. The infrared thermographic technique, which couples mechanical and thermal energy, offers …

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Centrifuge Model Tests To Identify Dynamic Properties Of Dense Sand For Site Response Calculations, David Stevens, Dan Wilson, Bruce Kutter, Byoungill Kim, Ahmed Elgamal Mar 2001

Centrifuge Model Tests To Identify Dynamic Properties Of Dense Sand For Site Response Calculations, David Stevens, Dan Wilson, Bruce Kutter, Byoungill Kim, Ahmed Elgamal

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

Four centrifuge models, tested on the large centrifuge at UC Davis, are described in this paper. These four experiments involved dense profiles of Nevada Sand (Dr = 90 to 100%) tested in two different model containers. The purpose of the experiments was to evaluate numerical site response procedures by comparison with model test data. In this paper we focus on determining basic material properties of one of the models by using in-flight measurements of shear wave velocity and calculations of stress-strain relationships using data from an extensive array of accelerometers. Shear wave velocity profiles were measured at centrifuge accelerations …

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Adjustment Method Of The Hysteresis Damping For Multiple Shear Spring Model, Osamu Ozutsumi, Susumu Iai Mar 2001

Adjustment Method Of The Hysteresis Damping For Multiple Shear Spring Model, Osamu Ozutsumi, Susumu Iai

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

In simulating the behavior of sandy soil under the cyclic loading condition using the multiple shear spring model, it is necessary to adjust the damping constant of the model. We describe a method for adjusting the constant in this paper. If you adopt the conventional Masing rule to decide the unloading curve of each spring, the entire damping constant of this model, which is superposition of those of all springs, would become larger than that measured in the laboratory for large strain level. Though the damping constant of each spring is controllable by amending the Masing rule, there is no …

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Probabilistic Analysis Of Wind Response Of Tall Structures Supported By Flexible Foundations, Amir M. Halabian, M. Hesham El Naggar Mar 2001

Probabilistic Analysis Of Wind Response Of Tall Structures Supported By Flexible Foundations, Amir M. Halabian, M. Hesham El Naggar

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

The effect of soil-structure interaction on the response of structures to dynamic loads has long been recognized and the deterministic approach is usually used for its evaluation. In most soil-structure interaction analyses, the soil shear wave velocity is used to characterize the stiffness of the soil and the foundation system. In practice, the shear modulus of the soil is difficult to evaluate and the natural spatial variability and the measurement technique affect its measured value. Probabilistic concepts are used to evaluate the significant design parameters of tall structures and to examine the sensitivity of their wind response to the variation …

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A Case Study On Safe Blast Design With Vibration Analysis, Bang-Woong Shin, Woo-Seok Bae, Jong-Kyu Lee, Byung-Chul An Mar 2001

A Case Study On Safe Blast Design With Vibration Analysis, Bang-Woong Shin, Woo-Seok Bae, Jong-Kyu Lee, Byung-Chul An

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

Safe delicacy blasting is necessarily to decrease safe problems resulting from blasting but if designs to consider only safety, it is a problem not to ensure economical gains because the effect of blasting is decreased. Therefore, blasting vibration must be predicted to consider given circumstances and ground conditions before blasting work, and then a design based on predicted result must be done. In this study, the testing blasting was carried out in two fields within a country, and then measured data for testing blasting were collected. The effect for blasting vibration was analyzed as the property of distance, charging gunpowder …

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Reflection And Refraction Of Quasi-P Wave Due To A Sandwich Isotropic Layer Between Two Monoclinic Half-Spaces, S. Saha, A. Chattopadhyay, D. Banerjee Mar 2001

Reflection And Refraction Of Quasi-P Wave Due To A Sandwich Isotropic Layer Between Two Monoclinic Half-Spaces, S. Saha, A. Chattopadhyay, D. Banerjee

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

The reflection and refraction of quasi-P(qP) wave below a transition isotropic layer sandwiched between two monoclinic media have studied. Due to incident of qP-wave at the interface of monoclinic lower half space and isotropic transition layer of thickness H, it will give rise to reflected qP, qSV, qSH-wave in the lower monoclinic half space and reflected P-wave and SV-wave at the isotropic transition layer of thickness H. As there is mother interface between transition layer and monoclinic upper-half space extended up to infinity, these two refracted P and SV-wave will incident at the interface with angle and 64 respectively. These …

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Natural Frequency Of Vertical Foundation Vibrations Evaluated From In-Situ Impact Test, Mark R. Svinkin Mar 2001

Natural Frequency Of Vertical Foundation Vibrations Evaluated From In-Situ Impact Test, Mark R. Svinkin

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

Local soil conditions play an important part in development of ground vibrations from machine foundations. A soil profile predominantly effects the natural frequencies of foundation vibrations. This paper presents a method for obtaining a pre-construction estimation of the natural frequency of damped vertical vibrations of foundations which will be built at a specific site for machines with dynamic loads. The method pertains principally to the relationship between foundation frequencies and the natural frequencies of the soil profiles at construction sites.

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Proposal On Non-Linear Response Analysis Method In Frequency, Susumu Nakamura, Nozomu Yoshida Mar 2001

Proposal On Non-Linear Response Analysis Method In Frequency, Susumu Nakamura, Nozomu Yoshida

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

The objective of this report is to propose a non-linear response analysis method in frequency domain based on the stress and strain relationship of soil in frequency domain. First of all, a new model for the strain and frequency dependent characteristics between shear modulus and damping constant with respect to the complex shear modulus is proposed, considering the following two characteristics; One is the similarity of stress-strain relationship between time domain and frequency domain. The other one is a non-stationary characteristics in frequency domain caused by non-linearity of soil. A new non-linear dynamic response analysis method in frequency domain is …

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Numerical Simulation Of Active Fault Rupture Propagation Through Dry Soil, Dimitrios N. Loukidis, George Bouckovalas Mar 2001

Numerical Simulation Of Active Fault Rupture Propagation Through Dry Soil, Dimitrios N. Loukidis, George Bouckovalas

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

Numerical simulation of fault rupture propagation through dry soil was performed using the finite difference code FLAC. A Mohr-Coulomb elasto-plastic constitutive model with strain softening was used to simulate soil behavior. The bedrock motion, prescribed at the bottom boundary of the mesh, was based on relevant seismological theories and observations. A total of 42 parametric analyses were performed where the shear strain rate and the plastic shear strain contours were used for localizing the rupture propagation as a shear band. Parametric analyses show that results are sensitive to the assumed soil type and dilatancy angle, but not to the soil …

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Probabilistic Microzonation Of Urban Territories: A Case Of The Taipei City, Vladimir Sokolov, Chin-Hsuing Loh, Kuo-Liang Wen Mar 2001

Probabilistic Microzonation Of Urban Territories: A Case Of The Taipei City, Vladimir Sokolov, Chin-Hsuing Loh, Kuo-Liang Wen

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

An integrated approach for evaluating “site-dependent” seismic hazard in terms of ground-motion parameters, which are used for engineering purposes, is presented. The method is based on the probabilistic seismic hazard analysis in terms of Fourier acceleration spectra. A scheme that allows conversion of the Uniform Hazard Fourier spectra to “hazard-compatible” peak ground acceleration (PGA), and Uniform Hazard response spectra is described. The method has been applied for preliminary probabilistic microzonation of the Taipei basin (the Taipei city). The source, path and site effects are characterized separately on the basis of the analysis of large collection of ground-motion recordings obtained since …

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Effect Of K0 On Liquefaction Strength Of Silty Sand, Shun-Ichi Sawada, Ryouichi Sakuraba, Naoki Ohmukai, Takeko Mikami Mar 2001

Effect Of K0 On Liquefaction Strength Of Silty Sand, Shun-Ichi Sawada, Ryouichi Sakuraba, Naoki Ohmukai, Takeko Mikami

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

Authors measured K0-value in-situ using Self-boring lateral load tester (SBLLT) and Flat-diratometer (DMT). After that, a series of cyclic undrained torsional shear tests under the plane strain condition on anisotropically consolidated condition (K0-condition) has been performed using undisturbed tube sampling to investigate the relation between the liquefaction strength of isotropically consolidated condition (Rlisotropic) and K0-condition (RlK0). The result of these laboratory tests shows that the liquefaction strength defined as 7.5% shear strain in double amplitude of undisturbed silty sand is generally agreement between triaxial and torsional test with isotropically and …

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