Numerical analysis of seismically induced liquefaction in earth embankment foundations. Part II. Application of remedial measures

2003 ◽  
Vol 40 (4) ◽  
pp. 766-779 ◽  
Author(s):  
Korhan Adalier ◽  
Ogun Aydingun
Keyword(s):  
Experimental Data ◽  
Laboratory Tests ◽  
Numerical Results ◽  
Sand Layer ◽  
Remedial Measures ◽  
Sheet Pile ◽  
Benchmark Model ◽  
Earth Embankment ◽  
Using Data ◽  
Earthquake Effects

In Part I, a benchmark model without any liquefaction remediation countermeasure was considered and numerical results were compared with centrifuge experiment results. In Part II, three additional models with remediation are analyzed and compared with centrifuge experiments conducted on identical models. The countermeasures considered are densification of the sand layer by compaction, gravel berm surcharge, and sheet pile enclosure. In addition to comparing numerical results with experimental data for each model, the effect of each countermeasure relative to the benchmark model is also discussed. Insights into the dynamic behavior of the employed embankment–foundation and liquefaction countermeasure systems are provided. The results of this study show that computer simulation of earthquake effects on embankments with liquefiable foundations with and without several different retrofit measures is possible using data from conventional laboratory tests and a verified numerical procedure.Key words: liquefaction countermeasures, numerical modeling, coupled formulation, centrifuge, embankment, earthquakes.

Numerical analysis of seismically induced liquefaction in earth embankment foundations. Part I. Benchmark model

2003 ◽  
Vol 40 (4) ◽  
pp. 753-765 ◽  
Author(s):  
Ogun Aydingun ◽  
Korhan Adalier
Keyword(s):  
Experimental Data ◽  
Numerical Analysis ◽  
Analysis Procedure ◽  
Finite Element Code ◽  
Remedial Measures ◽  
Foundation Soil ◽  
Benchmark Model ◽  
Numerical Predictions ◽  
Earth Embankment ◽  
Fully Coupled

A numerical analysis has been performed for a clayey embankment founded on a liquefiable foundation soil using an effective stress based, fully coupled, finite element code called DIANA-SWANDYNE II. The results were compared with data obtained from centrifuge experiments. In Part I, the numerical method and the analysis procedure are explained. The results obtained for a series of three consecutive, increasing amplitude shaking events are presented. An attempt has been made to calibrate a benchmark model to be used in the application of different remedial measures which are discussed in Part II. The numerical predictions compared well with the experimental data and provided further insights into the dynamic behavior of embankment–foundation systems.Key words: liquefaction, numerical modeling, coupled formulation, centrifuge, embankment, earthquakes.

Diagnostics of metal samples using the results of experimental and theoretical study of positively charged microparticles formed upon sample destruction

2018 ◽  
Vol 84 (10) ◽  
pp. 23-28
Author(s):  
D. A. Golentsov ◽  
A. G. Gulin ◽  
Vladimir A. Likhter ◽  
K. E. Ulybyshev
Keyword(s):  
Experimental Data ◽  
Early Stage ◽  
Experimental Studies ◽  
Material Model ◽  
Total Charge ◽  
Cross Sectional ◽  
Practical Applications ◽  
Mechanical And Electrical Properties ◽  
Order Of Magnitude ◽  
Using Data

Destruction of bodies is accompanied by formation of both large and microscopic fragments. Numerous experiments on the rupture of different samples show that those fragments carry a positive electric charge. his phenomenon is of interest from the viewpoint of its potential application to contactless diagnostics of the early stage of destruction of the elements in various technical devices. However, the lack of understanding the nature of this phenomenon restricts the possibility of its practical applications. Experimental studies were carried out using an apparatus that allowed direct measurements of the total charge of the microparticles formed upon sample rupture and determination of their size and quantity. The results of rupture tests of duralumin and electrical steel showed that the size of microparticles is several tens of microns, the particle charge per particle is on the order of 10–14 C, and their amount can be estimated as the ratio of the cross-sectional area of the sample at the point of discontinuity to the square of the microparticle size. A model of charge formation on the microparticles is developed proceeding from the experimental data and current concept of the electron gas in metals. The model makes it possible to determine the charge of the microparticle using data on the particle size and mechanical and electrical properties of the material. Model estimates of the total charge of particles show order-of-magnitude agreement with the experimental data.

Modelling of catalyst pellet deactivation

1985 ◽  
Vol 50 (11) ◽  
pp. 2381-2395
Author(s):  
Alena Brunovská ◽  
Ján Buriánek ◽  
Ján Ilavský ◽  
Ján Valtýni
Keyword(s):  
Experimental Data ◽  
Numerical Results ◽  
Benzene Hydrogenation ◽  
Alumina Catalyst ◽  
Temperature Changes ◽  
Catalyst Pellet ◽  
Model Equations ◽  
Catalytic Poison

The diffusion and the shell progressive models of deactivation caused by irreversible chemisorption of a catalytic poison are presented for a single catalyst pellet. The method for solution of the model equations is proposed. The numerical results are compared with experimental data obtained by measuring concentration and temperature changes due to thiophene poisoning in benzene hydrogenation over a nickel-alumina catalyst.

Larger-Eddy Simulation of Velocity Fluctuation in a Mixing T-Junction

2012 ◽  
Vol 152-154 ◽  
pp. 1313-1318
Author(s):  
Tao Lu ◽  
Su Mei Liu ◽  
Ping Wang ◽  
Wei Yyu Zhu
Keyword(s):  
Experimental Data ◽  
Velocity Fluctuation ◽  
Flow Model ◽  
Numerical Results ◽  
Mean Square ◽  
Main Duct ◽  
Velocity Fluctuations ◽  
Eddy Simulation ◽  
Large Eddy ◽  
Les Model

Velocity fluctuations in a mixing T-junction were simulated in FLUENT using large-eddy simulation (LES) turbulent flow model with sub-grid scale (SGS) Smagorinsky–Lilly (SL) model. The normalized mean and root mean square velocities are used to describe the time-averaged velocities and the velocities fluctuation intensities. Comparison of the numerical results with experimental data shows that the LES model is valid for predicting the flow of mixing in a T-junction junction. The numerical results reveal the velocity distributions and fluctuations are basically symmetrical and the fluctuation at the upstream of the downstream of the main duct is stronger than that at the downstream of the downstream of the main duct.

Modeling of Coupled Bending and Torsion in Elastic Structures

1993 ◽  
Author(s):  
H. T. Banks ◽  
C. A. Smith
Keyword(s):  
Experimental Data ◽  
Numerical Results ◽  
Computational Results ◽  
Elastic Structures ◽  
Approximation Techniques ◽  
Flexural Vibrations ◽  
And Control

Abstract In this presentation we will report on joint efforts with D.J. Inman and his colleagues at MSL, SUNY at Buffalo, to develop viable models for the analysis and control of elastic structures exhibiting coupled torsional and flexural vibrations. A model for coupled torsion and bending is developed which incorporates Kelvin Voigt damping and warping. Approximation techniques are introduced and preliminary numerical results are discussed. Experimental data is presented and used to test our computational results.

scholarly journals Modelling Macrophage Infiltration into Avascular Tumours

2002 ◽  
Vol 4 (1) ◽  
pp. 21-38 ◽  
Author(s):  
C. E. Kelly ◽  
R. D. Leek ◽  
H. M. Byrne ◽  
S. M. Cox ◽  
A. L. Harris ◽  
...  
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Spatial Structure ◽  
Random Motion ◽  
Numerical Results ◽  
Macrophage Infiltration ◽  
Numerical Techniques ◽  
Model Predictions ◽  
Independent Experimental Data

In this paper a mathematical model that describes macrophage infiltration into avascular tumours is presented. The qualitative accuracy of the model is assessed by comparing numerical results with independent experimental data that describe the infiltration of macrophages into two types of spheroids: chemoattractant-producing (hepa-1) and chemoattractant-deficient (or C4) spheroids. A combination of analytical and numerical techniques are used to show how the infiltration pattern depends on the motility mechanisms involved (i.e. random motion and chemotaxis) and to explain the observed differences in macrophage infiltration into the hepa-1 and C4 spheroids. Model predictions are generated to show how the spheroid's size and spatial structure and the ability of its constituent cells influence macrophage infiltration. For example, chemoattractant-producing spheroids are shown to recruit larger numbers of macrophages than chemoattractant-deficient spheroids of the same size and spatial structure. The biological implications of these results are also discussed briefly.

scholarly journals Numerical and Experimental Investigation of a Rich Quench Lean Combustor Sector

1996 ◽  
Author(s):  
Johannes W. Koopman ◽  
Peter Griebel ◽  
Christoph Hassa
Keyword(s):  
Experimental Data ◽  
Experimental Investigation ◽  
Numerical Results ◽  
Detailed Knowledge ◽  
Complementary Information ◽  
Species Concentration ◽  
Flow Temperature ◽  
Nox Formation ◽  
Sector Model ◽  
Decisive Importance

The flow in a three sector model, representing a segment of an annular rich quench lean combustor for an aeroengine is investigated. Detailed knowledge of flow, temperature and species concentration distributions is of decisive importance to control the NOx formation, essential to the RQL concept. Velocities, temperatures and species concentrations are measured. They are partly used to aquire data on the inlet boundaries in the numerical calculation and partly used to compare with the numerical results. The calculation reveals many details which are not accesable in the experiment. It also shows the effects of the specific inlet dataset. Experimental data and numerical results furnish complementary information.

Comparison of Numerical Results and Experimental Data on Emission Production Processes in a Diesel Engine

2001 ◽  
Author(s):  
Hajime Ishii ◽  
Yuichi Goto ◽  
Matsuo Odaka ◽  
Andrei Kazakov ◽  
David E. Foster
Keyword(s):  
Experimental Data ◽  
Diesel Engine ◽  
Numerical Results ◽  
Production Processes

scholarly journals Liquefaction Susceptibility of an Earth Dam Foundation: A Case Study 

2021 ◽  
Author(s):  
Hatem karoui ◽  
Mounir Bouassida
Keyword(s):  
Ground Surface ◽  
Standard Penetration Test ◽  
Earth Dam ◽  
Sand Layer ◽  
Dam Foundation ◽  
Liquefaction Susceptibility ◽  
Numerical Predictions ◽  
Earth Embankment ◽  
Heterogeneous Foundation

Abstract Sidi El Barrak earth dam is a compacted earth embankment of height 28 m built in 1999 on a heterogeneous foundation with strong dominance of sandy formations. The dam foundation was subjected to several tests to predict its behavior against the liquefaction risk. Standard penetration test (SPT) results served to evaluate the liquefaction risk in an earthquake occurrence. This article, firstly, presents an interpretation of data collected from SPT tests. Determination of liquefaction risk resulted from the empirical methods proposed by Seed & Idriss, (1985) and Idriss & Boulanger, (2008). Obtained results by those methods showed that, for different earthquake magnitudes equal to 5.25, 6 and 6.75, the risk of liquefaction exists in the pure sand layer located between the ground surface and 15 m depth of the foundation of the earth dam. An UBC3D-PLM constitutive model was adopted for studying the numerical response of sand layer subjected to an earthquake of acceleration equal 0.2 g to estimate its liquefaction risk. Recorded SPT data and laboratory tests results served for the determination of geotechnical parameters of this model. From numerical predictions it revealed that the liquefaction risk is greater for an earthquake characterized by an acceleration equal 0.2g.

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