Effect of mechanical restraint on the rate of corrosion in concrete

1998 ◽  
Vol 25 (1) ◽  
pp. 81-86 ◽  
Author(s):  
N Hearn ◽  
J Aiello
Keyword(s):  
Mix Design ◽  
Concrete Repair ◽  
Accelerated Corrosion ◽  
One Dimensional ◽  
Mechanical Restraint ◽  
Corrosion Rates ◽  
Accelerated Corrosion Tests ◽  
The Matrix ◽  
The Relationship

Experimental work on prismatic concrete specimens was conducted to determine the relationship between mechanical restraint and the rate of corrosion. The current together with the changes in strain of the confining frame were monitored during the accelerated corrosion tests. The effect of mix design and cracking on the corrosion rates was also investigated. The results show that one-dimensional mechanical restraint retards the corrosion process, as indicated by the reduction in the steel loss. Improved quality of the matrix, with and without cracking, reduces the rate of steel loss. In the inferior quality concrete, the effect of cracking on the corrosion rate is minimal.Key words: corrosion, concrete, repair.

Study on the Mechanism of Rebar Corrosion Considering the Relationship between Corrosion and Crack Width

2007 ◽  
Vol 348-349 ◽  
pp. 481-484
Author(s):  
Jei Jun You ◽  
Han Seung Lee ◽  
Yoshiteru Ohno
Keyword(s):  
Stainless Steel ◽  
Crack Width ◽  
Corrosion Current ◽  
Reinforcement Corrosion ◽  
Accelerated Carbonation ◽  
Accelerated Corrosion ◽  
Cement Ratio ◽  
Accelerated Corrosion Tests ◽  
Rebar Corrosion ◽  
The Relationship

In this study, accelerated corrosion tests were conducted on concrete specimens with and without accelerated carbonation beforehand for the purpose of elucidating the effects of carbonation, cover depth, and water-cement ratio (W/C) on the reinforcement corrosion. During testing, the corrosion current between the anode steel and cathode stainless steel was measured to continuously monitor the progress of corrosion throughout the test period, thereby investigating the mechanism of reinforcement corrosion and the relationship between corrosion and crack width, as well as other parameters.

Strain Analysis of Corrosed Prestressed Concrete Beams on Fatigue Test

2011 ◽  
Vol 255-260 ◽  
pp. 355-359
Author(s):  
Jin Qing Jia ◽  
Fang Yu ◽  
Da Li Yao ◽  
Wei Qing Zhu
Keyword(s):  
Prestressed Concrete ◽  
Concrete Beams ◽  
Strain Analysis ◽  
Fatigue Loading ◽  
Test Results ◽  
Fatigue Load ◽  
Accelerated Corrosion ◽  
Corrosion Rates ◽  
The Relationship ◽  
Concrete Strain

In order to study the relationship between strains and corrosion levels of prestressed concrete beams uder fatigue loading, accelerated corrosion method is used to make various corrosion rates of prestressed steel strands. The beams have the same designs and submitted to the same maximum and minimum load during the test. With the corrosion level as main parameter, strains at different position of the beams, such as non-prestressed steel strain, concrete strain in compressive region at mid-span and prestressed steel strain are studied. The test results show that beams with different corrosion rates have the same “three-stage“ law on the development of non-prestressed steel maximum and residual strain,as well as concrete strain and prestress strain. The significant increase of concrete strain is generated due to corrosion after concrete cracking.The increase of non-prestressed steel strain is nearly proportional to the growth of corrosion under the same fatigue load. A relationship was found to be a function. It can be obtained the corrosion rate of prestressed steel when the stress of non-prestressed steel strains are measured.

Address of the President Dr E. D. Adrian, O. M., at the Anniversary Meeting, 1 December 1952

1953 ◽  
Vol 140 (901) ◽  
pp. 443-453
Keyword(s):  
Wave Theory ◽  
Physical World ◽  
Negative Energy ◽  
Wave Mechanics ◽  
First Order ◽  
The Matrix ◽  
Relationship Of ◽  
The Relationship ◽  
Made In

The Copley Medal is awarded to Professor Paul Adrien Maurice Dirac for is remarkable contributions to the quantum theory of elementary particles and ectromagnetic fields. All his work has a very distinctive quality, in that he has Shown how to make evident the relationship of the remote abstractions of the mathematician to the extremely practical problems facing the atomic Phyysicist. This appeared even in his earliest work, for in 1926 he took up the commutative algebra of Heisenberg, and solved the problem of a non- planetary orbit. Not long afterwards he showed how the ‘matrix’ of Heisenberg could be identified with the ‘wave mechanics’ of Schrödinger. It is this paper, with its development of the idea of ‘representations’ physical states, that more than any other has given the colour of his work. The advances made in 1927 had not provided a relativistically invariant for the electron, nor had they explained the phenomenon of ‘electron’. In 1928 he remedied both of these defects at the same time. Perhaps the quality of this work was that it replaced the second order of equations, universal in wave-theory, by equations of the first order. These equa- had some astonishing consequences, such as possible states of negative energy; and Dirac attempted a physical interpretation of these states by Le concept of a background of electrons occupying nearly all such states. An state appeared in the physical world to be a particle of electronic and positive charge, equal in magnitude to that of the electron. The ‘positive electron’ or ‘positron’ was actually only discovered several years later and it into Dirac’s scheme.

scholarly journals How Much of Usable Matrix is Necessary to Suppress Fragmentation Effect? An Individual Based Model of Population Extinction

2020 ◽  
Author(s):  
Bruno Travassos-de-Britto ◽  
José Miranda ◽  
Pedro Rocha
Keyword(s):  
Computational Models ◽  
Landscape Management ◽  
Single Population ◽  
Individual Based Model ◽  
Population Extinction ◽  
Matrix Quality ◽  
The Matrix ◽  
Relationship Of ◽  
The Relationship

AbstractThe use of the matrix has been considered an important factor in landscape ecology, as it can change the relationship of the population with the configuration of the landscape. There are indications that the usability of the matrix is a factor that can help mitigate the effect of further fragmentation. Using a systematic way to assess the effect of matrix quality in fragmented landscapes could lead to a better understanding of this system. We built a computational individual based model capable of simulate bi-dimensional landscapes and individuals that inhabit that landscape. We explored how changes in the level of fragmentation and matrix quality affected time of permanence of a single population in the landscape. As the quality of the matrix changes from very unsuitable to very suitable, the number of situations in which fragmentation reduces the time of permanence of the population changes from frequent to rare. In addition, as most of the organisms can survive in a sub-optimum habitat, the cases in which fragmentation has real effect on populations’ permanence are even fewer then stated by Fahrig. The result indicates that the proportion of intermediate habitat necessary to suppress fragmentation effect should follow the percentage of usability of these intermediate habitat until it falls under 50% of usability, and with less than 30% of usability, intermediate habitats are not able to suppress fragmentation effect. An index to measure the usability of elements of the matrix should be an important tool relating computational models and landscape management.

Cyclic corrosion tests of organometallic coated fuel tanks

2016 ◽  
Vol 63 (2) ◽  
pp. 89-96 ◽  
Author(s):  
Patrícia Alves Saliba ◽  
Milene Adriane Luciano ◽  
Maria das Mercês Reis Castro ◽  
Vanessa Freitas Cunha Lins
Keyword(s):  
Electron Microscopy ◽  
Accelerated Corrosion ◽  
Content Type ◽  
Corrosion Tests ◽  
Accelerated Corrosion Tests ◽  
Fuel Tanks ◽  
Steel Tanks ◽  
Galvannealed Steel ◽  
Scanning Electron

Purpose – The purpose of this study is to evaluate the quality of organometallic coatings of automotive fuel tanks. Galvannealed steels and galvannealed steels coated with organometallic layers were analyzed using accelerated corrosion tests. Design/methodology/approach – The characterization of galvannealed and organometallic coatings was done by mass (layer removal and weighing) and layer thickness (glow discharge optical emission spectroscopy and scanning electron microscopy), chemical composition (energy dispersive spectroscopy) and surface morphology (scanning electron microscopy). The accelerated corrosion tests were performed in accordance with SAE J2334 and GMW 14872 standards. Findings – The samples tested using the GMW 14872 standard were more deteriorated as compared to the samples submitted to the SAE J2334 test because of the higher degree of aggressiveness of the GMW 14872 test. Despite the presence of white rust, the corrosion resistance of organometallic-coated steel samples was higher as compared to the resistance of galvannealed steel samples. Research limitations/implications – The organometallic coating is a commercial product, whose chemical composition is confidential. Practical implications – This study reinforces the quality of automotive tanks with organometallic coating and helps to increase their competitiveness in the market tanks as compared to polymeric tanks. Social implications – The study contributes to increase the competitiveness of steel tanks against polymeric tanks that meet the technical requirements but are not environmentally friendly because they are multi-layered and cannot be recycled. Originality/value – The novelty of this study is the comparison of the corrosion resistance of galvannealed steel tanks and galvannealed steel tanks with organometallic coatings. This corrosion evaluation joined with the physical and chemical characterization was not found in literature and is relevant to the materials selection of the automotive industry.

The Relationship Between Interoception and Metacognition

2016 ◽  
Vol 30 (2) ◽  
pp. 76-86 ◽  
Author(s):  
Judith Meessen ◽  
Verena Mainz ◽  
Siegfried Gauggel ◽  
Eftychia Volz-Sidiropoulou ◽  
Stefan Sütterlin ◽  
...  
Keyword(s):  
Memory Performance ◽  
Memory Task ◽  
Demographic Characteristics ◽  
Metacognitive Awareness ◽  
Interoceptive Awareness ◽  
Future Research ◽  
Heartbeat Perception ◽  
Interoceptive Accuracy ◽  
The Relationship

Abstract. Recently, Garfinkel and Critchley (2013) proposed to distinguish between three facets of interoception: interoceptive sensibility, interoceptive accuracy, and interoceptive awareness. This pilot study investigated how these facets interrelate to each other and whether interoceptive awareness is related to the metacognitive awareness of memory performance. A sample of 24 healthy students completed a heartbeat perception task (HPT) and a memory task. Judgments of confidence were requested for each task. Participants filled in questionnaires assessing interoceptive sensibility, depression, anxiety, and socio-demographic characteristics. The three facets of interoception were found to be uncorrelated and interoceptive awareness was not related to metacognitive awareness of memory performance. Whereas memory performance was significantly related to metamemory awareness, interoceptive accuracy (HPT) and interoceptive awareness were not correlated. Results suggest that future research on interoception should assess all facets of interoception in order to capture the multifaceted quality of the construct.

The relationship between optimism, personal control and quality of life of patients with COPD

2002 ◽  
Author(s):  
R. Arnold ◽  
A. V. Ranchor ◽  
N. H. T. ten Hacken ◽  
G. H. Koeter ◽  
V. Otten ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Personal Control ◽  
The Relationship

Using the alveograph in developing requirements for the quality of flour for wafer sheet production

2020 ◽  
Vol 29 (12) ◽  
pp. 52-58
Author(s):  
E.P. Meleshkina ◽  
◽  
S.N. Kolomiets ◽  
A.S. Cheskidova ◽  
◽  
...  
Keyword(s):  
Rheological Properties ◽  
Quality Indicators ◽  
Wheat Flour ◽  
Mathematical Statistics ◽  
Intended Purpose ◽  
The Future ◽  
Relationship Of ◽  
The Relationship

Objectively and reliably determined indicators of rheological properties of the dough were identified using the alveograph device to create a system of classifications of wheat and flour from it for the intended purpose in the future. The analysis of the relationship of standardized quality indicators, as well as newly developed indicators for identifying them, differentiating the quality of wheat flour for the intended purpose, i.e. for finished products. To do this, we use mathematical statistics methods.

HUBUNGAN KUALITAS KEHIDUPAN KERJA TERHADAP KINERJA PERAWAT PELAKSANA

2019 ◽  
Vol 9 (4) ◽  
pp. 413-420
Author(s):  
Amella Gusty ◽  
Dachriyanus Dachriyanus ◽  
Leni Merdawati
Keyword(s):  
District Hospital ◽  
Simple Random Sampling ◽  
Work Life ◽  
Quality Of Work Life ◽  
P Value ◽  
Work Context ◽  
Cross Sectional ◽  
Quality Of Work ◽  
The Relationship

Kinerja perawat merupakan hasil yang dicapai dalam melaksanakan asuhan keperawatan di rumah sakit. Terciptanya asuhan keperawatan yang optimal sangat diperlukan dukungan dari pihak rumah sakit salah satunya adalah menciptakan kualitas kehidupan kerja baik bagi perawat. Penelitian ini bertujuan untuk mengetahui hubungan antara kualitas kehidupan kerja terhadap kinerja perawat pelaksana di RSUD Teluk Kuantan. Jenis penelitian kuantitatif dengan pendekatan cross sectional. Jumlah sampel 120 responden yang diperoleh melalui proportionate simple random sampling. Hasil penelitian menunjukkan kualitas kehidupan kerja perawat RSUD Teluk Kuantan berada pada kategori sedang, kinerja perawat berada pada kategori kurang baik. Berdasarkan analisis kedua variabel teridentifikasi bahwa tidak ada hubungan antara kualitas kehidupan kerja dengan kinerja perawat pelaksana dengan  p value 0,817. Dimensi work context merupakan komponen yang memiliki hubungan dengan kinerja perawat pelaksana dengan p value 0,008, dimensi work life  tidak berhubungan secara signifikan dengan kinerja perawat. Kesimpulan penelitian diketahui tidak ada hubungan antara kualitas kehidupan kerja dengan kinerja perawat pelaksana. Ada hubungan dimensi work context dengan kinerja perawat pelaksana. Tidak ada hubungan dimensi work life dengan kinerja perawat.   Kata kunci: kualitas kehidupan kerja, kinerja, perawat pelaksana   THE RELATIONSHIP BETWEEN THE QUALITY OF WORK LIFE AND THE PERFORMANCE OF IMPLEMENTERS NURSES   ABSTRACT Nurse performance is the result achieved in implementing nursing care in a hospital. The creation of optimal nursing care is very much needed support from the hospital, one of which is to create a good quality of work life for nurses. This study aims to determine the relationship between the quality of work life and the performance of nurses at the Kuantan District Hospital. This type of quantitative research with cross sectional approach. The number of samples of 120 respondents obtained through proportionate simple random sampling. The results showed that the quality of work life of nurses at the Kuantan District Hospital was in the medium category, the nurses' performance was in the unfavorable category. Based on the analysis of the two variables, it was identified that there was no relationship between the quality of work life with the performance of implementing nurses with a p value of 0.817. The work context dimension is a component that has a relationship with the performance of nurses implementing with p value 0.008, the dimension of work life does not significantly correlate with nurse performance. The conclusion of the research is that there is no relationship between the quality of work life and the performance of the implementing nurses. There is a relationship between the dimensions of the work context and the performance of the nurses. There is no relationship between the dimensions of work life and nurse performance.   Keywords: quality of work life, performance, implementers nurse

Management of Economics and State "Bottom"

2020 ◽  
Vol 17 (6) ◽  
pp. 76-91
Author(s):  
E. D. Solozhentsev
Keyword(s):  
Quality Of Life ◽  
Artificial Intelligence ◽  
Probabilistic Models ◽  
Human Life ◽  
Special Software ◽  
Human Quality ◽  
Relationship Of ◽  
The Relationship

The scientific problem of economics “Managing the quality of human life” is formulated on the basis of artificial intelligence, algebra of logic and logical-probabilistic calculus. Managing the quality of human life is represented by managing the processes of his treatment, training and decision making. Events in these processes and the corresponding logical variables relate to the behavior of a person, other persons and infrastructure. The processes of the quality of human life are modeled, analyzed and managed with the participation of the person himself. Scenarios and structural, logical and probabilistic models of managing the quality of human life are given. Special software for quality management is described. The relationship of human quality of life and the digital economy is examined. We consider the role of public opinion in the management of the “bottom” based on the synthesis of many studies on the management of the economics and the state. The bottom management is also feedback from the top management.

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