Pressuremeter Testing of Normally Consolidated Clays—The Effects of Varying Test Technique

AbstractAlthough BS 5930:1981 describes both Menard and self-boring pressuremeter tests, little guidance is given on test methods. A number of techniques, both stress controlled and strain controlled, have been used and it has been shown that for clays the test technique has a significant influence on the derived strength and modulus parameters.When a pressuremeter test is carried out in a clay, it is assumed that shearing occurs under undrained conditions. However, in addition to immediate shear strain, some creep and local consolidation will occur in the soil around the expanding borehole. These two phenomena are time-dependent and variations in test technique will affect the test data and hence the derived strength and modulus values.To obtain a better understanding of these effects, pressuremeter tests have been studied both experimentally and numerically. Experimentally, pressuremeter tests have been simulated by expanding cylindrical cavities in samples of three clays prepared with known stress history and the results compared with numerical predictions where the effects of immediate shear, creep and consolidation can be separated. The experimental results compare well with the numerical predictions.This has given a new insight into the behaviour of clay soils during pressuremeter tests. The results indicate that any simple standardization of pressuremeter test technique should be approached with caution.

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Current-Signature-Based Analysis of Complex Test Fails

ISTFA 1999: Conference Proceedings from the 25th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa1999p0377 ◽

1999 ◽

Author(s):

Anne E. Gattiker ◽

Phil Nigh ◽

Wojciech Maly

Keyword(s):

Failure Analysis ◽

Physical Nature ◽

Channel Length ◽

Test Methods ◽

Multiple Test ◽

Physical Mechanisms ◽

Test Behavior ◽

Complex Test ◽

Current Signature ◽

Insight Into

Abstract This article provides an analysis of a class of failures observed during the SEMATECH-sponsored Test Methods Experiment. The analysis focuses on use of test-based failure analysis and IDDQ signature analysis to gain insight into the physical mechanisms underlying such subtle failures. In doing so, the analysis highlights techniques for understanding failure mechanisms using only tester data. In the experiment, multiple test methods were applied to a 0.45 micrometer effective channel length ASIC. Specifically, ICs that change test behavior from before to after burn-in are studied to understand the physical nature of the mechanism underlying their failure. Examples of the insights provided by the test-based analysis include identifying cases where there are multiple or complex defects and distinguishing cases where the defect type is likely to be a short versus an open and determining if the defect is marginal. These insights can be helpful for successful failure analysis.

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Quantifying electron transit in donor-bridge-acceptor systems using probabilistic confidence

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633618500463 ◽

2018 ◽

Vol 17 (07) ◽

pp. 1850046 ◽

Cited By ~ 2

Author(s):

Evan Curtin ◽

Gloria Bazargan ◽

Karl Sohlberg

Keyword(s):

Charge Transport ◽

Conditional Probability ◽

Probabilistic Approach ◽

Probability Analysis ◽

Time Dependent ◽

Quantum Particles ◽

Transit Times ◽

Conditional Probability Analysis ◽

Insight Into ◽

Dependent Probability

A probabilistic approach to characterizing transit times for quantum particles is generalized to a system of more than two spatial regions and applied to the transport of charge in donor-bridge-acceptor systems. The approach is based on applying conditional probability analysis to a discrete representation of the time-dependent probability density as generated by numerical solution of the time-dependent Schrödinger equation for an initially localized electron. To carry out this analysis, it is first necessary to cast the conditional probability analysis approach in matrix form. The results afford a quantification of the electron transit time and may provide a tool to gain insight into the mechanism of charge transport.

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Time-dependent barrier passage of one-dimensional fractional damping reactive system

International Journal of Modern Physics B ◽

10.1142/s0217979218502855 ◽

2018 ◽

Vol 32 (26) ◽

pp. 1850285

Author(s):

Chun-Yang Wang ◽

Zhao-Peng Sun ◽

Ming Qing ◽

Yu-Qing Xu

Keyword(s):

Transmission Coefficient ◽

Brownian Particle ◽

Time Dependent ◽

Reactive System ◽

Damping Properties ◽

Flux Method ◽

Fractional Damping ◽

One Dimensional ◽

Reactive Process ◽

Insight Into

The time-dependent barrier passage of a Brownian particle diffusing in the fractional damping environment is studied by using the reactive flux method. Characteristic quantities such as the rate constant and stationary transmission coefficient are computed for a thimbleful of insight into the barrier escaping dynamics. Results show that the barrier recrossing of the fractional damping reactive system is obviously weakened. And the nonmonotonic varying of the stationary transmission coefficient reveals a close dependence of the escaping process on the fractional damping properties. The time-dependent barrier passage of one-dimensional fractional damping reactive process is found very similar to the two-dimensional non-Ohmic case.

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Unsteady deformations of a free liquid surface caused by radiation pressure

Journal of Fluid Mechanics ◽

10.1017/jfm.2011.236 ◽

2011 ◽

Vol 682 ◽

pp. 460-490 ◽

Cited By ~ 13

Author(s):

B. ISSENMANN ◽

R. WUNENBURGER ◽

H. CHRAIBI ◽

M. GANDIL ◽

J.-P. DELVILLE

Keyword(s):

Analytical Model ◽

Radiation Pressure ◽

Liquid Surface ◽

Acoustic Pulse ◽

Free Liquid Surface ◽

Time Dependent ◽

Surface Dynamics ◽

Fluid Interface ◽

Numerical Predictions ◽

Strongly Damped

We present an analytical model of the time-dependent, small-amplitude deformation of a free liquid surface caused by a spatially localized, axisymmetric, pulsed or continuous, acoustic or electromagnetic radiation pressure exerted on the surface. By exactly solving the unsteady Stokes equation, we predict the surface dynamics in all dynamic regimes, namely inertial, intermediate and strongly damped regimes. We demonstrate the validity of this model in all dynamic regimes by comparing its prediction to experiments consisting of optically measuring the time-dependent curvature of the tip of a hump created at a liquid surface by the radiation pressure of an acoustic pulse. Finally, we present a numerical scheme simulating the behaviour of a fluid–fluid interface subjected to a time-dependent radiation pressure and show its accuracy by comparing the numerical predictions with the analytical model in the intermediate and strongly damped regimes.

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In situ testing and its application to foundation engineering

Canadian Geotechnical Journal ◽

10.1139/t86-086 ◽

1986 ◽

Vol 23 (4) ◽

pp. 573-594 ◽

Cited By ~ 36

Author(s):

P. K. Robertson

Keyword(s):

Test Methods ◽

Load Test ◽

Foundation Engineering ◽

Penetration Test ◽

In Situ Testing ◽

Cone Penetration ◽

Specific Test ◽

Pressuremeter Test ◽

In Situ Test

The status of in situ testing and its application to foundation engineering are presented and discussed. The in situ test methods are discussed within the framework of three groups: logging, specific, and combined test methods. The major logging test methods discussed are standard penetration test (SPT), cone penetration test (CPT), and the flat plate dilatometer test (DMT). The major specific test methods discussed are the prebored pressuremeter test (PMT), the self-bored pressuremeter test (SBPMT), and the screw plate load test (SPLT). Discussion is also presented on recent tests that combine features of logging tests (using the CPT) and specific tests (e.g. the seismic, the electrical resistivity/dielectric, and the lateral stress sensing cone penetration tests). A brief discussion is also presented on the applicability, as perceived by the author, of existing in situ test methods and the future of in situ testing applied to foundation engineering. Key words: in situ testing, foundation engineering, penetration testing, pressuremeter.

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Theoretical insight into the photophysical properties of six heteroleptic Ir(iii) phosphorescent complexes bearing ppy-type ligands

Photochemical & Photobiological Sciences ◽

10.1039/c9pp00218a ◽

2019 ◽

Vol 18 (11) ◽

pp. 2766-2772 ◽

Cited By ~ 1

Author(s):

Deming Han ◽

Lihui Zhao ◽

Xuerong Han

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Photophysical Properties ◽

Time Dependent ◽

Functional Theory ◽

Theoretical Insight ◽

Insight Into ◽

Dependent Density

By using density functional theory and time-dependent density functional theory, the geometrical, electronic and photophysical properties of six complexes with two ppy-type ligands and one acetylacetone anion around the Ir center have been explored.

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Centrifugal Flow in a Rotor-Stator Cavity

Journal of Fluids Engineering ◽

10.1115/1.1949645 ◽

2005 ◽

Vol 127 (4) ◽

pp. 787-794 ◽

Cited By ~ 32

Author(s):

Sébastien Poncet ◽

Roland Schiestel ◽

Marie-Pierre Chauve

Keyword(s):

Laser Doppler Anemometer ◽

Second Order ◽

Control Parameters ◽

Complex Flows ◽

Order Model ◽

Pressure Transducers ◽

Numerical Predictions ◽

Two Component ◽

First Time ◽

Insight Into

The present work considers the turbulent flow inside an annular rotor-stator cavity with and without centrifugal throughflow. Extensive measurements performed using a two-component laser-Doppler anemometer technique, and pressure transducers are compared to numerical predictions based on one-point statistical modeling using a low-Reynolds-number second-order full-stress transport closure. A study of the flow control parameters is performed, and, for the first time, a better insight into the transition from Batchelor to Stewartson types of flow is gained from this study. The advanced second-order model is confirmed to be the adequate level of closure to describe such complex flows.

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