Comparison between laboratory and in situ values of the coefficient of primary consolidation cv

2002 ◽  
Vol 39 (1) ◽  
pp. 103-110 ◽  
Author(s):  
Giampaolo Cortellazzo
Keyword(s):  
Curve Fitting ◽  
Soil Layer ◽  
The Other ◽  
Consolidation Theory ◽  
Fitting Procedures ◽  
Primary Consolidation ◽  
Clay Layers ◽  
Oedometer Tests

Many curve-fitting procedures based on the Terzaghi uncoupled consolidation theory have been proposed for determination of the laboratory coefficient of primary consolidation, cv. This paper presents data from 10 oedometer tests performed on clay samples from three different sites, with the cv values having been obtained using four different fitting procedures. The in situ settlements of the clay layers were measured using borehole extensometers. In this way the in situ cv values of the same clay were determined and compared with the laboratory values. At times, the four methods show considerable differences in the values of cv determined in the laboratory. Casagrande's method gives values that differ from those of the other methods and is not always easily usable. The other three methods provide a more consistent evaluation of the values cv. The comparison between in situ and laboratory cv values is not straight forward, since these findings show that the macrostructure of the soil layer influences the behaviour of the whole layer, and the laboratory cv values, apart from the method used for their determination, are sometimes unable to interpret settlement over time.Key words: clay, coefficient of primary consolidation, consolidation, embankment.

A Comparison of Five Curve-Fitting Procedures in Radioimmunoassay

1986 ◽  
Vol 23 (6) ◽  
pp. 694-698 ◽  
Author(s):  
Jennifer A Nisbet ◽  
J A Owen ◽  
Gail E Ward
Keyword(s):  
Binding Site ◽  
Curve Fitting ◽  
The Other ◽  
Practical Advantage ◽  
Analytical Precision ◽  
Fitting Procedures ◽  
Best Fit ◽  
Single Binding Site ◽  
Better Than

Data obtained from routine analytical radioimmunoassays were processed using five curve-fitting procedures, viz. ‘Amersham’, single binding site, four parameter logistic, a linear logit-log and a polynomial logit-log. The polynomial logit-log procedure gave the best fit, but this was probably due to the inherent flexibility of this curve-fitting process since the analytical precision achieved with it was no better than what was obtained with most of the other procedures. A limited study failed to show that statistical weighting of data before curve fitting had any practical advantage.

scholarly journals Two Novel Techniques for Determination of Polysaccharide Cross-Links Show that Crh1p and Crh2p Attach Chitin to both β(1-6)- and β(1-3)Glucan in the Saccharomyces cerevisiae Cell Wall

2009 ◽  
Vol 8 (11) ◽  
pp. 1626-1636 ◽  
Author(s):  
Enrico Cabib
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Wall ◽  
Acetic Acid ◽  
Yeast Cell ◽  
Cell Walls ◽  
Double Mutant ◽  
The Other ◽  
Cross Links

ABSTRACT Previous work, using solubilization of yeast cell walls by carboxymethylation, before or after digestion with β(1-3)- or β(1-6)glucanase, followed by size chromatography, showed that the transglycosylases Crh1p and Crh2p/Utr2p were redundantly required for the attachment of chitin to β(1-6)glucan. With this technique, crh1Δ crh2Δ mutants still appeared to contain a substantial percentage of chitin linked to β(1-3)glucan. Two novel procedures have now been developed for the analysis of polysaccharide cross-links in the cell wall. One is based on the affinity of curdlan, a β(1-3)glucan, for β(1-3)glucan chains in carboxymethylated cell walls. The other consists of in situ deacetylation of cell wall chitin, generating chitosan, which can be extracted with acetic acid, either directly (free chitosan) or after digestion with different glucanases (bound chitosan). Both methodologies indicated that all of the chitin in crh1Δ crh2Δ strains is free. Reexamination of the previously used procedure revealed that the β(1-3)glucanase preparation used (zymolyase) is contaminated with a small amount of endochitinase, which caused erroneous results with the double mutant. After removing the chitinase from the zymolyase, all three procedures gave coincident results. Therefore, Crh1p and Crh2p catalyze the transfer of chitin to both β(1-3)- and β(1-6)glucan, and the biosynthetic mechanism for all chitin cross-links in the cell wall has been established.

Improved Techniques for Assessment of Plasma Lipoprotein Patterns. I. Precipitation in Gels after Electrophoresis with Polyanionic Compounds

1973 ◽  
Vol 19 (7) ◽  
pp. 737-739 ◽  
Author(s):  
Dietrich Seidel ◽  
Heinrich Wieland ◽  
Claudia Ruppert
Keyword(s):  
Differential Diagnosis ◽  
Plasma Lipoprotein ◽  
The Other ◽  
New Technique ◽  
Specific Antiserum ◽  
Fast Determination

Abstract A method is described for making lipoprotein fractions visible by polyanion precipitation in situ in the gels after electrophoresis. With the new technique the pattern and its interpretation in the differential diagnosis of all primary forms of hyperlipoproteinemia is the same as for the other lipid-staining procedures. The new technique is simpler to perform, reliable, and provides the required information 60 min after electrophoresis. It also allows a very fast determination of the abnormal lipoprotein (LP-X) that characterizes cholestasis, without use of a specific antiserum.

Rapid method of consolidation testing

1999 ◽  
Vol 36 (2) ◽  
pp. 392-400 ◽  
Author(s):  
A Sridharan ◽  
H B Nagaraj ◽  
N Srinivas
Keyword(s):  
Rapid Method ◽  
Curve Fitting ◽  
Considerable Time ◽  
Coefficient Of Consolidation ◽  
Load Increment ◽  
Rectangular Hyperbola ◽  
Fitting Procedures ◽  
Time Required ◽  
Earth Retaining Structures

The determination of consolidation characteristics forms an important aspect in the design of foundations and other earth-retaining structures. The conventional consolidation test as originally proposed by Terzaghi takes considerable time (more than 15 days in highly compressible soils with low coefficient of consolidation) and effort. Any effort to reduce the duration of testing will be desirable from several considerations. In this paper, an attempt has been made to propose a rapid method of consolidation testing. In the proposed method, the next load increment is applied as soon as the necessary time required to identify the percent consolidation is reached and to evaluate the coefficient of consolidation by one of the popular curve-fitting procedures. The rectangular hyperbola method has been used to identify the percent consolidation reached after any load increment, and to determine the coefficient of consolidation, before making the next load increment. The time required to complete the test using the rapid consolidation method could be as low as 4-5 h compared with 1 or 2 weeks in the case of the conventional consolidation test.Key words: clays, compressibility, consolidation, settlements, soil tests.

scholarly journals In-situ Measurements in Overconsolidated Clay

2015 ◽  
Vol 3 (1-2) ◽  
pp. 68-76
Author(s):  
Eszter Horvath-Kalman
Keyword(s):  
Earth Pressure ◽  
Young Modulus ◽  
In Situ Measurements ◽  
The Other ◽  
Physical Parameters ◽  
Measurement Results ◽  
Processing Of Measurement Results ◽  
Overconsolidated Soils

Abstract The study is about the general genesis process of overconsolidated soils, as well as the effects of the overconsolidated ratio to structures. It will demonstrate the possible methods for the determination of the values of overconsolidated ratio and of earth pressure at rest and of the other soil-physical parameters; further, the processing of measurement results, through which the values of OCR (Overconsolidated ratio) and of λ0 (Earth pressure at rest) and of c, E soil-physical parameters (friction angles, cohesion and Young modulus) in the Kiscelli Clay Marl have been determined by Selfboring Pressuremeter.

scholarly journals Characteristics of strength-deformation of loess-like deposits and ground structure in Vietnam National University-Ho Chi Minh city

2013 ◽  
Vol 16 (2) ◽  
pp. 38-47
Author(s):  
Hoang Minh Truong ◽  
Xinh Xuan Nguyen ◽  
Loi Thi Thuy Bui
Keyword(s):  
Surface Soil ◽  
Soil Layer ◽  
Ho Chi Minh City ◽  
Structure Model ◽  
Ground Structure ◽  
Model Base ◽  
National University ◽  
Surface Soil Layer ◽  
Oedometer Tests

Researched the strength, deformation, sudden settlement by water of the surface soil layer. Discussed about the ground base on a structure model. Applied for planning, calculating design and foundation in the Vietnam National University - Hochiminh City at Thu Duc district. Carried out to test the basic geotechnical properties and the special tests such as in situ compression and oedometer tests with unsaturation and saturation; monitored deformation, and changes of cohesion, C (kgf/cm2), friction angl , φ (d gr ) in various conditions ith the time. Analysed the structure of soil under the microscope. Built the ground structure model base on the surveied data.

A very rapid in situ Kikuchi technique to determine relative crystal misorientation

1988 ◽  
Vol 46 ◽  
pp. 830-831
Author(s):  
J. I. Bennetch
Keyword(s):  
Electron Beam ◽  
Analytical Techniques ◽  
Superplastic Forming ◽  
The Other ◽  
Kikuchi Pattern ◽  
Kikuchi Line ◽  
Line Analysis

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

Determination of the Burgers vector of a dislocation in a Fe-Mn alloy by weak-beam image in HVEM

1978 ◽  
Vol 36 (1) ◽  
pp. 330-331
Author(s):  
Y. Ishida ◽  
H. Ishida ◽  
K. Kohra ◽  
H. Ichinose
Keyword(s):  
High Order ◽  
Simulation Technique ◽  
The Other ◽  
Image Simulation ◽  
Diffraction Vector ◽  
Burgers Vector ◽  
Weak Beam ◽  
Beam Image ◽  
Edge Component

IntroductionA simple and accurate technique to determine the Burgers vector of a dislocation has become feasible with the advent of HVEM. The conventional image vanishing technique(1) using Bragg conditions with the diffraction vector perpendicular to the Burgers vector suffers from various drawbacks; The dislocation image appears even when the g.b = 0 criterion is satisfied, if the edge component of the dislocation is large. On the other hand, the image disappears for certain high order diffractions even when g.b ≠ 0. Furthermore, the determination of the magnitude of the Burgers vector is not easy with the criterion. Recent image simulation technique is free from the ambiguities but require too many parameters for the computation. The weak-beam “fringe counting” technique investigated in the present study is immune from the problems. Even the magnitude of the Burgers vector is determined from the number of the terminating thickness fringes at the exit of the dislocation in wedge shaped foil surfaces.

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