bluuebunny/crossref_metadata_2025_split huggingface dataset:
An assessment, using three field studies, of the theoretical concept of the efficiency of drainage layers in an embankment
Authors: Sills G. C. 
Published: October 2009

The efficiency of drainage layers in an embankment has been defined in terms of the pore-pressure dissipation (Gibson and Shefford, 1968). In order to relate this to field experience, three embankments have been studied. In each case, the pore-water pressure that might be expected to develop in the absence of drainage was calculated. This was then compared with the measured pore-pressure, to obtain an estimate of the degree of dissipation due to the drainage system. By relating this to the calculated efficiency, the theoretical concept can be assessed in comparison with observed behaviour. L'efficacité des couches de drainage d'un remblai se définit (d'après Gibson et Shefford, 1968) selon la dissioation de la pression interstitiélle. L'éetude de trois remblais a été effectée dans le but de comparer cet concept avec des résultats pratiques. Dans chacun des cas en question, on a calculeé la pression d'eau interstitielle à laquelle on pouvait s'attendre en l'absence de tout drainage. Puis une comparaison fut effectuée avec la pression interstitielle enregistrée, en vue d'obtenir une évaluation du niveau de dissipation provenant du sysètme de drainage. Un rapport fut alors établi entre le résultat obtenu et l'efficacité calculée, permettant ainsi une évaluation de la notion théorique au moyen d'une comparaison avec le comportement effectif.
The determination of stress fields from plane strain data
Authors: Endicott L. J. 
Published: October 2009

Two new methods of analysis for obtaining stress fields from plane strain data are derived. The two methods are mutually independent, each using strain parameters and a stress–strain relationship of a type different from that used by the other. Two solutions of stress fields are presented being obtained by using the two methods of analysis. The strain data used for the solutions are taken from one stage of a laboratory test. Thus the two stress distributions should be identical. The two solutions are compared and found to be in agreement. The application of the second new method of analysis to the problem of solving bearing pressure and slope stability problems is discussed and an example is given. On établit deux nouvelles méthodes analytiques afin d'obtenir des zones de résistance à partir des données de deformation plane. Les deux méthodes sont mutuellement indépendantes. Chacune se sert des paramètres de déformation ainsi que de tel rapport entre la résistance et la déformation qui diffère de celui dont se sert l'autre. On présente deux solutions pour les zones de réistance qui sont obtenues à partie des deux méthodes analytiques en question. D'une partie d'essai de laboratoire on obtient les donées de déformation réquises dans les dites solutions. Les deux distributions de déformation doivent être done identiques. Une comparaison des deux solutions révèlent qu'elles soient conformes. On discute—d'ailleurs un exemple est cité à titre—l'application de la deuxième nouvelle méthode analytique afin de résoudre les problèmes de charge et de stabilité de talus.
Dynamic displacements of offshore structures due to low frequency sinusoidal loading
Authors: Smith I. M. , Molenkamp F. 
Published: October 2009

Two of the most important aspects of foundation design for cyclic loading conditions are the assessment of material degradation due to cycling (the fatigue problem) and of dynamic amplification of the foundation response (the resonance problem). The first of these seems hardly amenable to calculation at all, except in the form of back-analysis of laboratory element and model test data or of field observations. The second, on the other hand, seems ill-suited to laboratory investigation and may therefore be estimated by calculation. For this purpose a simple bilinear soil model is presented and evaluated in comparison with a linearized equivalent. The performance of the model in relation to fatigue predictions is also explored. L'évaluation de la dégradation des matériaux due aux charges cycliques (problème de la fatigue), d'une part, et l'évaluation de l'empliflcation dynamique de la ré des fondations (problème de la résonance), d'autre part, constituent deux des aspects les plus importants de la réalisation de fondations soumis à des charges cycliques. Dans le Premier de ces cas, toute forme de calcul semble pratiquement impossible, mise à part l'analyse à rebours de données d'essais de modèles et éléments en laboratoire ou d'observations in situ. Le second cas, par contre, se prête mal aux recherches en laboratoire et peut donc être évalué par calcul. C'est dans ce but qe'st, présenté un modè de sol bilinéaire simple, lequel est évalué et comparé à un équivalent linéarisé. La performance du modèle par rapport aux prévisions de fatigue fait également l'objet d'une étude.
Design of the retaining walls for the M25 cut and cover tunnel at Bell Common
Authors: Hubbard H. W. , Potts D. M. , Miller D. , Burland J. B. 
Published: October 2009

The M25 motorway forms part of the London orbital road and at two locations north of London (Holmesdale, Waltham Cross, and Bell Common, Epping) it is constructed in cut and cover tunnels for environmental reasons. The Bell Common Tunnel is underlain by London clay and the design of the embedded cantilever retaining walls revealed considerable uncertainties in the assessment of the bending moments. Moreover application of the stability requirements of the code of practice (CP2) gave rise to excessive wall penetrations. Part I of the Paper describes the initial design approach to the retaining walls and highlights the lack of guidance that exists for this type of construction. Part II describes the results of a study that was commissioned to assess the soil-structure interaction of the retaining walls at Bell Common together with a review of stability criteria. The decisions leading to the final design are then described. L'autoroute M25 fait partie de la rocade périphérique de Londres. Pour des raisons d'environnement elle a été construite en tunnels de faible profondeur (excavation suivie de remblai) sur deux sites au nord de Londres (Holmesdale à Waltham Cross et Bell Common à Epping). Le tunnel Bell Common repose sur l'argile de Londres et la construction des murs de soutènement cantilever ont montré que l'évaluation des moments de flexion était très incertaine. Le respect des exigences des règlements (CP2) concernant la stabilité a aussi entraîné des pénétrations excessives du mur. La première partie de cet article décrit l'attitude prise dès le commencement au sujet de la construction des murs de soutènement et souligne qu'il existe bien peu d'indications sur la manière correcte d'effectuer ce genre de travaux. La deuxième partie de l'article présente les résultats d'une étude qui a été entreprise spécialement pour évaluer l'interaction solouvrage des murs de soutènement à Bell Common. L'article passe en revue les critères de stabilité et décrit les choix d'après lesquels la construction définitive a été réalisée.
Undrained cyclic loading on a saturated dense sand stratum
Authors: Lee F. H. , Foo S. L. 
Published: October 2009

An analytical approach using finite elements is employed to study the validity of a hypothesis for explaining the presence of spiky acceleration records observed in centrifuge model earthquake tests on embankments and islands. This hypothesis attributes the presence of spiky acceleration records to the recoupling of motions caused by the transient recovery of stiffness of the dense sand in a state of cyclic mobility. The analyses show that spiky acceleration records similar to those observed experimentally can be generated analytically in the problem of a saturated dense sand layer if the material behaviour is of a hardening type. These acceleration spikes coincide with the onset of the hardening phase, thus supporting the above hypothesis. The analyses also show that this type of acceleration response cannot be obtained if the material behaviour is of a softening type. As the behaviour of saturated dense sand under undrained cyclic loading belongs to the hardening type, the mechanism discussed in this Paper may be present in such sand layers when the latter is subjected to earthquake loadings. Une méthode d'analyse aux éléments finis a eté employée pour étudier la validité d'une hypothèse expliquant la présence des pics d'accélération retrouvés dans les enregistrements d'essais sis-miques en centrifuge effectúes pour des remblais et des îles. L'hypothése explique la présence des pics d'accélération dans les enregistrements par le recouplement des mouvements causés par la récupération transitoire de la rigidité dn sable dense dans un état de mobilité cyclique. Les analyses démontrent qu'il est possible de produire par analyse des enregistrements avec des pics d'accélération analogues à ceux observés expérimentalement dans le cas du problème d'une couche saturée de sable dense, à condition que la matière soit d'un type qui s'endurcit. Les pics d'accélération coïncident avec le commencement de la phase d'endurcissement, renforçant de la sorte l'hypothèse en question. Les analyses indiquent aussi que ce genre de réponse à accélération ne peut pas se produire si la matière est d'un type qui se ramollit. Vu que le sable dense sature s'endurcit sous le chargement cyclique non-drainé, le mécanisme discuté dans cet article peut être présent dans de telles couches de sable lorsque le sable est soumis à des chargements sismiques.
Automatic orientation analysis of particles of soil microstructures
Authors: Luo D. , Macleod J. E. S. , Leng X. , smart P. 
Published: October 2009

In studying soil microstructure, the orientations of soil particles and of the voids between them are two of the most important factors. In this Paper, the directed vein method and the convex hull method are proposed for automatic orientation analysis of soil microstructure. In the directed vein method a directed vein image of the boundaries of the particles in an electron micrograph of soil structure is constructed using a chain code, and the expected directions of a directed vein are calculated to provide the orientation of the vein. In the convex hull method simple polygons are constructed from the boundaries, the convex hulls of the simple polygons are built up, and the longest diagonal of each convex hull is selected, the direction of which is taken as the orientation of the particle. Before either method can be applied, image preprocessing must be carried out to find the boundaries of the particles. Both methods involve simpler programming, faster computing and less storage than do other methods. Les orientations des particules du sol et des vides entre ces particules représentent deux des facteurs les plus importants dans I'étude de la microstructure des sols. L'article propose pour I'analyse automatique des orientations dans la microstructure des sols une méthode dite à veine dirigée et une méthode dite à enveloppe convexe. Dans la méthode à veine dirigée on construit, à I'aide d'un code à chaîne une image à veine dirigée des limites des particules dans un micrographe électronique de la structure du sol, après quoi on calcule les directions attendues d'une veine dirigée pour fournir I'orientation de la veine. Dans la méthode à enveloppe convexe on construit des polygones simples à partir des limites, on construit des enveloppes convexes de polygones simples et on choisit la diagonale la plus longue de chaque enveloppe convexe, sa direction est admise comme I'orientation de la particule. Avant I'application de I'une ou de I'autre de ces méthodes il faut prétraiter I'image afin d'obtenir les limites des particules. En comparaison avec d'autres méthodes, ces deux méthodes présentent I'advantage de programmes simplifiés, de calculs plus rapides et de mémoires réduites.
Interpretation of constant head in situ permeability tests in soil zones of finite extent
Authors: Bromhead E. N. 
Published: October 2009

This paper considers the effect of performing a constant head in situ permeability test on spherical piezometers in soil zones of finite extent. The finite extent of the seepage domain is shown to cause a change in slope in the plot of the experimental results—an effect which is widely found in practice. Some fully analytical solutions are presented; in other cases, for which no closed-form solution has yet been found, results obtained from finite element calculations are used in support of the arguments. Inferences are drawn on the test procedure and the interpretation of field data. Cet article décrit l'effet de mesures de perméabilités in-situ dans des zones de sol d'extension fine sur des piézmètres sphériques. Uextension réduite de la zone d'influence cause un changement de pente sur les courbes expérimentales. Cet effet est fréquemment rencontré en pratique. Quelques solutions analytiques sont pré sentées. Dans d'autres cas, pour lesquels aucune forme fermée n'a pu &circitre déterminée, des résultats, obtenus par la m6thode des éléments finis, sont utilisés. Des conclusions en sont tirées pour la mise en oeuvre de procédures de test et l'interprétation de donmées de terrains.
A lower-bound analysis for torsion in concrete frames
Authors: Mansur M.A. , Rangan B.V. 
Published: October 2009

Synopsis This paper presents the development of a theory for predicting the strength of reinforced concrete indeterminate frames in which the members are subjected to bending as well as twisting moments and transverse shear. The theory has been applied to two types of simple indeterminate frame -the frames being statically indeterminate by one and three degrees. The predictions of the theory are compared with the test results of the authors as well as those reported in the literature. The agreement is reasonably good.
Load–deflection curves for fibre-reinforced concrete beams in flexure
Authors: Hughes B. P. , Fattuhi N. I. 
Published: October 2009

Synopsis The paper examines the effects of the addition of various fibres, including fibrillated and monofilament polypropylene, as well as round straight, Duoform, crimped and hooked steel, upon the flexural load-deflection properties of a basic concrete matrix at three different ages. The flexural and splitting strengths of the beams were increased with the addition of steel fibres, especially for those with efficient forms of mechanical anchorage, such as Duoform and hooked steel. The fracture toughness of reinforced beams was increased considerably for all the fibres used.
Fracture mechanics and concrete behaviour
Authors: Kotsovos Michael D. , Newman John B. 
Published: October 2009

Synopsis A fracture mechanism for concrete valid under any state of stress and which can be used to predict observed deformational behaviour is postulated on the basis of theoretical considerations regarding the extension of a crack within a brittle elastic medium. This fracture mechanism forms the basis of an analysis of experimental data on the deformational response of concrete under various states of triaxial stress, and has led to a comprehensive description of the fracture processes of the material under generalized loading conditions.
An experimental study of early thermal cracking in reinforced concrete
Authors: Hughes B. P. , Ghunaim F. 
Published: October 2009

Synopsis Restrained volume changes in concrete can cause cracking before normal service loads are applied, since all concrete members undergo an early thermal cycle due to the heat of hydration. This mechanism of early thermal cracking is reviewed and an experimental laboratory investigation is described which tested the validity of the current proposals in BS 5337 for some different types, arrangements and amounts of reinforcement. Of the types of reinforcement investigated, the fabric was found, as expected, to give the best crack width control. It was confirmed that, provided a minimum ratio of reinforcement is present in reinforced concrete, thermal crack widths are a function of reinforcement ratio, reinforcement diameter, strength of concrete and bond strength between reinforcement and concrete.
Socioeconomic Status and Body Mass Index Among Hispanic Children of Immigrants and Children of Natives
Authors: Balistreri Kelly Stamper , Van Hook Jennifer 
Published: October 2009

Objectives. We examined how Hispanic parents' income and education, combined with their nativity status, influenced the body mass index (BMI) of their children, compared with non-Hispanic White children and their parents. Methods. We used data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998–99 to estimate linear growth curve models of children's initial BMI in kindergarten and change in BMI through fifth grade. Socioeconomic status was measured by logged household income and parental educational attainment (less than high school, high school graduate, some college, college graduate or higher). Results. Parental education was negatively associated with children's BMI (baseline and growth) for non-Hispanic White children. Among Hispanic children, the association of parental education with growth in BMI was negative but much weaker. The weak effect of parental education was not explained by the presence of immigrants in the Hispanic population. Income was strongly negatively associated with children's BMI in kindergarten among children of Hispanic and White natives, but positively associated among Hispanic immigrant families. Conclusions. The positive income–BMI association among Hispanic immigrant children might reflect cultural differences that immigrant parents carry with them from their countries of origin.
Risk of Alcohol-Impaired Driving Recidivism Among First Offenders and Multiple Offenders
Authors: Rauch William J. , Zador Paul L. , Ahlin Eileen M. , Howard Jan M. , Frissell Kevin C. , Duncan G. Doug 
Published: October 2009

Objectives. We sought to determine the statewide impact of having prior alcohol-impaired driving violations of any type on the rate of first occurrence or recidivism among drivers with 0, 1, 2, or 3 or more prior violations in Maryland. Methods. We analyzed more than 100 million driver records from 1973 to 2004 and classified all Maryland drivers into 4 groups: those with 0, 1, 2, or 3 or more prior violations. The violation rates for approximately 21 million drivers in these 4 groups were compared for the study period 1999 to 2004. Results. On average, there were 3.4, 24.3, 35.9, and 50.8 violations per 1000 drivers a year among those with 0, 1, 2, or 3 or more priors, respectively. The relative risks for men compared with women among these groups of drivers were 3.8, 1.2, 1.0, and 1.0, respectively. Conclusions. The recidivism rate among first offenders more closely resembles that of second offenders than of nonoffenders. Men and women are at equal risk of recidivating once they have had a first violation documented. Any alcohol-impaired driving violation, not just convictions, is a marker for future recidivism.
The Effect of Less-Lethal Weapons on Injuries in Police Use-of-Force Events
Authors: MacDonald John M. , Kaminski Robert J. , Smith Michael R. 
Published: October 2009

Objectives. We investigated the effect of the use of less-lethal weapons, conductive energy devices (CEDs), and oleoresin capsicum (OC) spray on the prevalence and incidence of injuries to police officers and civilians in encounters involving the use of force. Methods. We analyzed data from 12 police departments that documented injuries to officers and civilians in 24 380 cases. We examined monthly injury rates for 2 police departments before and after their adoption of CEDs. Results. Odds of injury to civilians and officers were significantly lower when police used CED weapons, after control for differences in case attributes and departmental policies restricting use of these weapons. Monthly incidence of injury in 2 police departments declined significantly, by 25% to 62%, after adoption of CED devices. Conclusions. Injuries sustained during police use-of-force events affect thousands of police officers and civilians in the United States each year. Incidence of these injuries can be reduced dramatically when law enforcement agencies responsibly employ less-lethal weapons in lieu of physical force.
Chronic Maternal Dietary Chromium Restriction Modulates Visceral Adiposity
Authors: Padmavathi Inagadapa J.N. , Rao K. Rajender , Venu Lagishetty , Ganeshan Manisha , Kumar K. Anand , Rao Ch. Narasima , Harishankar Nemani , Ismail Ayesha , Raghunath Manchala 
Published: October 2009

OBJECTIVE
We demonstrated previously that chronic maternal micronutrient restriction altered the body composition in rat offspring and may predispose offspring to adult-onset diseases. Chromium (Cr) regulates glucose and fat metabolism. The objective of this study is to determine the long-term effects of maternal Cr restriction on adipose tissue development and function in a rat model.

RESEARCH DESIGN AND METHODS
Female weanling WNIN rats received, ad libitum, a control diet or the same with 65% restriction of Cr (CrR) for 3 months and mated with control males. Some pregnant CrR mothers were rehabilitated from conception or parturition and their pups weaned to control diet. Whereas some CrR offspring were weaned to control diet, others continued on CrR diet. Various parameters were monitored in the offspring at three monthly intervals up to 15–18 months of age.

RESULTS
Maternal Cr restriction significantly increased body weight and fat percentage, especially the central adiposity in both male and female offspring. Further, the expression of leptin and 11 β-hydroxysteroid dehydrogenase 1 genes were significantly increased in CrR offspring of both the sexes. Adipocytokine levels were altered in plasma and adipose tissue; circulating triglyceride and FFA levels were increased, albeit in female offspring only. Rehabilitation regimes did not correct body adiposity but restored the circulating levels of lipids and adipocytokines.

CONCLUSIONS
Chronic maternal Cr restriction increased body adiposity probably due to increased stress and altered lipid metabolism in WNIN rat offspring, which may predispose them to obesity and associated diseases in later life.
Adipocyte Turnover: Relevance to Human Adipose Tissue Morphology
Authors: Arner Erik , Westermark Pål O. , Spalding Kirsty L. , Britton Tom , Rydén Mikael , Frisén Jonas , Bernard Samuel , Arner Peter 
Published: October 2009

OBJECTIVE
Adipose tissue may contain few large adipocytes (hypertrophy) or many small adipocytes (hyperplasia). We investigated factors of putative importance for adipose tissue morphology.

RESEARCH DESIGN AND METHODS
Subcutaneous adipocyte size and total fat mass were compared in 764 subjects with BMI 18–60 kg/m2. A morphology value was defined as the difference between the measured adipocyte volume and the expected volume given by a curved-line fit for a given body fat mass and was related to insulin values. In 35 subjects, in vivo adipocyte turnover was measured by exploiting incorporation of atmospheric 14C into DNA.

RESULTS
Occurrence of hyperplasia (negative morphology value) or hypertrophy (positive morphology value) was independent of sex and body weight but correlated with fasting plasma insulin levels and insulin sensitivity, independent of adipocyte volume (β-coefficient = 0.3, P &lt; 0.0001). Total adipocyte number and morphology were negatively related (r = −0.66); i.e., the total adipocyte number was greatest in pronounced hyperplasia and smallest in pronounced hypertrophy. The absolute number of new adipocytes generated each year was 70% lower (P &lt; 0.001) in hypertrophy than in hyperplasia, and individual values for adipocyte generation and morphology were strongly related (r = 0.7, P &lt; 0.001). The relative death rate (∼10% per year) or mean age of adipocytes (∼10 years) was not correlated with morphology.

CONCLUSIONS
Adipose tissue morphology correlates with insulin measures and is linked to the total adipocyte number independently of sex and body fat level. Low generation rates of adipocytes associate with adipose tissue hypertrophy, whereas high generation rates associate with adipose hyperplasia.