Sphere Penetration Experiments In Vertically Vibrated Sand,
2010
Université Catholique de Louvain, Belgium
Sphere Penetration Experiments In Vertically Vibrated Sand, Nicolas Denies, Jean Canou, Jean-Noël Roux, Alain Holeyman
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The paper concerns vibrodriving and vibrocompaction processes applied to granular soils and presents experiments able to characterize the behaviour of sand subjected to vertical vibration. Soil degradation phenomena arising during vibro-driving are first described and the vibro-fluidization of dry granular matter is discussed. The paper concentrates on the shear strength degradation of vibrated dry granular soils. Vertical vibration is then particularly investigated. The volume change during vertical vibration is described and the sand behaviour during vibration is also discussed. One focuses on the influence of the acceleration on the dry density after vibration. Finally, new sphere penetration experiments (SPE) based …
Method To Reduce Variability Of S-Wave Profiles In Seismic Cone Penetration Tests,
2010
Belgian Nuclear Research Centre/ Vrije Universiteit Brussel, Belgium
Method To Reduce Variability Of S-Wave Profiles In Seismic Cone Penetration Tests, Lou Areias
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The pseudo method used to calculate shear wave velocity (Vs) in seismic cone penetration (SCP) tests often generates high variability of Vs values at shallow depths. This occurs when travel paths are small and signal variability large to allow accurate arrival time differentiation between successive signals. The offset distance between the source and receivers has the largest influence on signal variability. A method described in this paper shows good results in reducing Vs variability of SCP tests during post processing. The method consists of increasing the sampling interval to calculate Vs and then regrouping the data …
P-Wave Reflection Imaging Of Laboratory Soil Models,
2010
University of California, Los Angeles, CA
P-Wave Reflection Imaging Of Laboratory Soil Models, Joseph Coe, Scott J. Brandenberg
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
An ultrasonic p-wave reflection imaging system is used to non-invasively image submerged soil models with embedded anomalies and complex geometric layer contacts. The ultrasonic transducers emit compressive waves into water that subsequently transmit into the underlying soil, and measurements of the reflections are used to construct the images. Properties of the transducers and data acquisition hardware and software are explained. A soil model consisting of embedded high- and low-impedance anomalies, dipping soil layer contacts, and an undulating concrete base layer was imaged using 500 kHz transducers. The geometric features of the model are clearly visible in the images.
A New Method For Evaluating Spatial Variability Of Soil Strains Developed During Earthquakes Based On Electrical Resistivity Concepts Using Green’S Function,
2010
AMEC Geomatrix, Inc., Oakland, CA
A New Method For Evaluating Spatial Variability Of Soil Strains Developed During Earthquakes Based On Electrical Resistivity Concepts Using Green’S Function, Zhihua Li
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
A new method for evaluating spatial variability of soil strains during earthquakes is developed. The idea is based on electrical resisitivity concepts. By solving the classic Maxwell’s equations applying Green’s function for the boundary conditions, we obtained a closed form solution relating the electric potential measurements to the soil’s displacements during earthquakes. The displacement information can be further used to obtain soil strains. In centrifuge models, the displacement measurements using an electrode switching system have been demonstrated to have spatial and temporal resolutions of 1 mm and 1 ms. Based on the high resolution of the displacement that is obtainable, …
Passive Earth Pressure Force-Displacement Relationships,
2010
University of California at San Diego, La Jolla, CA
Passive Earth Pressure Force-Displacement Relationships, Patrick Wilson, Ahmed Elgamal
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
During a strong earthquake, passive earth pressure can provide resistance to excessive displacements along bridge abutments and pile caps. To account for this contribution, the force-displacement relationship is required, in addition to the peak resistance value. Experiments were performed at the University of California, San Diego to record the passive earth pressure force-displacement relationship behind a 1.7 meter tall vertical wall section. The experimental configuration of the soil container and wall system is described first. Backfill consisting of dense well-graded silty sand was placed in the soil container which measured 5.6 meters long, 2.9 meters wide and 2.15 meters deep. …
Applicability Test Of Soil Improvement Using Micro-Bubbles Against Soil Liquefaction,
2010
Sato Kogyo Co., Ltd., Japan
Applicability Test Of Soil Improvement Using Micro-Bubbles Against Soil Liquefaction, Koichi Nagao, Naoaki Suemasa, Tatsuo Akashi, Mikio Futaki
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The purpose of this paper is to demonstrate the effectiveness of micro-bubble water injection method against soil liquefaction based on the result of seismic vibration test using large scale flexible shaking box. It is well known that soil resistance to liquefaction increases as the degree of saturation of the soil decreases, but the practical method to decrease the saturation of the soil has not been invented. The authors solved this problem by new method of injecting water containing micro-air bubbles into the ground. The method has an advantage which not only simple and cost-effective but also friendly to environment. We …
Shake Table Testing To Quantify Seismic Soil-Structure-Interaction Of Underground Structures,
2010
California Polytechnic State University, San Luis Obispo, CA
Shake Table Testing To Quantify Seismic Soil-Structure-Interaction Of Underground Structures, Robb Eric S. Moss, Vic Crosariol, Steven Kuo
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
This research uses shake table testing of scale soil-structure models to mimic the coupled seismic response of underground structures and surrounding/supporting soil (termed soil-structural-interaction or SSI). Currently the seismic design of subways and other critical underground infrastructure rely on little to no empirical data for calibrating numerical simulations. This research is working towards filling that empirical data gap. The research is composed of two phases, the first a validation of the free-field response of a flexible wall barrel filled with model soil, the second a test to measure the “racking” deformations induced in a model subway cross-section embedded in the …
Experiences In Pumice Soil Characterization By Surface Wave Analysis,
2010
Geotechnical consultant, Mexico
Experiences In Pumice Soil Characterization By Surface Wave Analysis, Salvador Lazcano
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Guadalajara, México, is a large city located mainly over a thick deposit (up 100 m) of pumice, in a seismic zone. Then, besides the stiffness of pumice soils, it is important to predict their behavior under seismic movements. Pumice soils are so crushable that SPT or CPT does not adequately characterize them. As a complement or alternative to SPT, CPT and other field testing, in recent years there has been a gradual increment in the use of surface wave analysis for soil characterization, by measuring shear wave velocity (VS). ReMi is one of the surface wave analysis methods …
Field Measurement Of Dynamic Soil Properties Of Tropical Meta-Sediment Residual Soils,
2010
Universiti Kebangsaan Malaysia, Malaysia
Field Measurement Of Dynamic Soil Properties Of Tropical Meta-Sediment Residual Soils, Zamri Chik, Susy K. Ariestianty, Sri Atmaja P. Rosyidi, Khairul Anuar Mohd. Nayan, Mohd. Raihan Taha
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The study area which was located in Peninsular Malaysia comprised of residual meta-sedimentary soil derived Kenny Hill Formation. The dynamic soil properties of tropical meta-sediment residual soils were measured using non-destructive seismic method known as Multi-channel Analysis of Surface Wave (MASW) method. Twenty four geophones were located on ground in order to measure surface wave propagation. By inversion of dispersion curve, the shear wave velocity profile could be calculated and obtained. For most site investigations, other conventional method of field testing had been conducted such as drilling and Standard Penetration Test (SPT). This paper, however, attempts to obtain the comprehensively …
Innovative Triaxial/Resonant Column Equipment,
2010
University of Pisa, Italy
Innovative Triaxial/Resonant Column Equipment, Diego Carlo Federico Lo Presti, Nunziante Squeglia, Oronzo Pallara
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The present paper describes a new triaxial apparatus which allows the measurement of low strain stiffness by means of both bender elements and resonant column test. In a previous paper Squeglia et al. (2009) described the innovative use of bender elements as receivers for the measurement of shear wave velocity. The proposed technique is synthetically described with the further development of apparatus which allow to perform resonant column test during a triaxial test. Since the apparatus has not been designed as a resonant column device, some critical points have been dealt with. Some tests have been dedicated to solve the …
Multi-Modal Synthesis And Variable Modulus Effects In Resonant Column Tests By Random Excitations,
2010
Iowa State University, Ames, IA
Multi-Modal Synthesis And Variable Modulus Effects In Resonant Column Tests By Random Excitations, Jeramy C. Ashlock, Ronald Y. S. Pak
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
To extend current measurement and data synthesis techniques for resonant column testing, random vibration transfer functions measured using a modified 6 inch (152.4 mm) diameter Drnevich free-free resonant column device are evaluated against viscoelastic theories of homogeneous and heterogeneous soil models. By means of the transfer function approach, it is found that the first four resonant peaks of the soil column response can be captured experimentally with some instrumental adaptations. By calibration against theoretical transfer functions, the ability to characterize the modulus and damping properties of the soil samples over a broad range of frequencies is demonstrated. As a generalization …
Review Of Available Methods For Evaluation Of Soil Sensitivity For Seismic Design,
2010
University of Western Ontario, Canada
Review Of Available Methods For Evaluation Of Soil Sensitivity For Seismic Design, Osama Abuhajar, M. Hesham El Naggar, Tim Newson
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Sensitivity describes the effect of soil disturbance/remoulding on shear strength. Cyclic stresses during seismic events may lead to varying levels of disturbance and remoulding of brittle sensitive clays. The Canadian Foundation Engineering Manual (CFEM) recommends site-specific evaluation of the seismic hazard, including site response analysis, for sites that have quick or highly sensitive clays. Different levels of soil sensitivity have been shown in different versions of CFEM and their errata. The current manual CFEM (2006) classifies clay as highly sensitive if its sensitivity is greater than 40 (classified as Class F soil). However, there is considerable variation within the literature …
Observations And Analysis Of Ground Motion And Pore Pressure At The Nees Instrumented Geotechnical Field Sites,
2010
University of California Santa Barbara, Santa Barbara, CA
Observations And Analysis Of Ground Motion And Pore Pressure At The Nees Instrumented Geotechnical Field Sites, Jamison H. Steidl, Sandra H. Seale
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The Garner Valley and Wildlife sites are producing a large data set that includes very interesting observations from earthquakes in the magnitude 4 to 7 range, with peak accelerations of ~10%g, at the threshold where nonlinear effects start to become important. In addition, hundreds of smaller earthquakes are recorded each month that provide the control data representing the linear behavior of the site. With the larger motions, we begin to see pore pressure build up on the liquefaction array at both the NEES Garner Valley Array site and at the NEES Wildlife Liquefaction Array site. We present the results of …
Influence Of Densification Method On Some Aspects Of Undrained Silty Sand Behavior,
2010
Oregon State University, Corvallis, OR
Influence Of Densification Method On Some Aspects Of Undrained Silty Sand Behavior, Mehmet Murat Monkul, Jerry A. Yamamuro
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Different specimen preparation methods such as moist tamping, dry funnel deposition, slurry deposition, dry air pluviation have been reported in the literature to investigate the undrained behavior of silty sands. Similarly, different means have been used to densify the soils prepared with such methods. Ongoing research shows that the change in undrained behavior (e.g. change in initial peak deviator stress and instability angle) due to different deposition densities is significantly affected by the densification technique utilized within a particular deposition method. It is believed that those variations are closely related with changes in the initial soil fabric that is achieved …
New Methods To Remove Arsenic From Soils,
2010
Shri Rawatpura Sarkar Institute of Technology, India
New Methods To Remove Arsenic From Soils, R. N. Khare
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
In Chhattisgarh State, arsenic content in soil is usually moderate to high. However, on some industrial sites like in Bhilai Steel Plant Bhilai, certain effluent discharges can lead to high concentrations of this chemical in the soil. After periods of rainfall and runoff, arsenic can also be found in water. In this context, Indian researchers investigated the potential of contaminations to remove arsenic from contaminated soils and waters. In addition, Electrokinetic model is developed in laboratory which has shown that, depending on soil conditions, these models are able to remove heavy metals in polluted soils by 85-90%. Overall, this research …
Attenuation Of Traffic Induced Ground Borne Vibrations Due To Heavy Vehicles,
2010
Middle East Technical University, Turkey
Attenuation Of Traffic Induced Ground Borne Vibrations Due To Heavy Vehicles, Ozgur L. Ertugrul, Deniz Ulgen
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Traffic induced vibrations, which are transmitted through the ground, may interfere with the proper operation of vibration sensitive equipments and cause nuisance on local population. Influence of these vibrations on surrounding buildings and sensitive devices play an important role on acceptance of the projects. In this study, main objective is the estimation of ground-borne vibration levels due to operation of heavy vehicles at two different sites where soil type and stratification significantly differs. For this purpose, site specific vibration surveys are conducted. A series of dynamic finite element modeling analyses are performed to predict actual vibration records at measurement points. …
Coupled Cwt Spectrogram Analysis And Filtration: New Approach For Surface Wave Analysis (A Case Study On Soft Clay Site),
2010
Muhammadiyah University of Yogyakarta, Indonesia
Coupled Cwt Spectrogram Analysis And Filtration: New Approach For Surface Wave Analysis (A Case Study On Soft Clay Site), Sri Atmaja P. Rosyidi, Mohd. Raihan Taha, Zamri Chik
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Surface wave analysis consists of generation, measurement and processing of the dispersive Rayleigh waves recorded from two or more vertical transducers. However, in case of soft clay soil, the reliable dispersion curve is difficult to be produced particularly at the frequency below 20 Hz. Some noises from nature and other human-made sources may disturb the generated surface wave data. In this paper, coupled analysis of continuous wavelet transform (CWT) spectrogram analysis based on Gaussian Derivative function was used to analyze the seismic waves in different frequency and time. First analysis is time-frequency wavelet spectrogram which was employed to localize the …
Dynamic Analysis Of Piles Under Lateral Harmonic Vibration,
2010
K.N. Toosi University of Technology, Iran
Dynamic Analysis Of Piles Under Lateral Harmonic Vibration, Mahmoud Ghazavi, Ahmad Dehghanpour
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
This paper presents a new mathematical approach for the analysis of harmonically vibrating horizontal, linear, elastic uniform pile. The soil properties may vary from layer to layer. No separation is allowed at the soil-pile interface. The pile is modeled as a number of cylindrical segments connected by rigid nodes. The length of each segment is chosen such that the effects of the soil inhomogenity are accounted for. The governing differential equation for an arbitrary pile segment is obtained and solved. According to the pile support types such as pinned, fixed and free conditions, first an arbitrary appropriate value for either …
Dynamic Behavior Of An Elastic Beam On A Winkler Foundation Under A Moving Load,
2010
Istanbul Technical University, Turkey
Dynamic Behavior Of An Elastic Beam On A Winkler Foundation Under A Moving Load, Abdul Hayir
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The purpose of this study is to investigate the response of an elastic beam on a Winkler foundation under a moving load. The load is assumed as a moving harmonic load and the beam is considered as an infinite Bernoulli-Euler beam with constant cross-section. The approach of Winkler foundation for the elastic foundation is very common in the practical applications although it does not accurately represent the continuous characteristic of the foundations. In this model the interaction between the vertical springs is only considered. In the solutions of the problem, the double Fourier Transform is applied and for its invention …
Geotechnical Seismic Isolation By Scrap Tire-Soil Mixtures,
2010
University of Hong Kong, Hong Kong
Geotechnical Seismic Isolation By Scrap Tire-Soil Mixtures, Hing-Ho Tsang, Nelson T. K. Lam, Saman Yaghmaei-Sabegh, M. Neaz Sheikh, Buddhima Indraratna
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The stockpiling of scrap tires is a significant threat to our environment and has been a hot topic amongst the engineering community which has been looking for long term viable solutions to the recycling and reuse of rubber tires. This paper proposes a new method of utilizing scrap tires for applications in infrastructure protection forming part of the solution strategy. The method involves mixing scrap tire particles with soil materials and placing the mixtures around civil engineering systems, for vibration absorption. The inexpensive nature of the proposed method can be of great benefits to developing countries where there are affordability …
