Effect of Specimen Geometry on the Predicted Mechanical Behavior of Polyethylene Pipe Material

2014 ◽  
Author(s):  
Tarek M. A. A. El-Bagory ◽  
Tawfeeq A. R. Alkanhal ◽  
Maher Y. A. Younan
Keyword(s):  
Mechanical Behavior ◽  
Longitudinal Direction ◽  
Primary Objective ◽  
The Other ◽  
Pipe Material ◽  
Ring Specimen ◽  
Design Data ◽  
Practical Applications ◽  
Other Hand ◽  
Gauge Section

The primary objective of the present paper is to depict the mechanical behavior of high density polyethylene, (HDPE), pipes under different loading conditions with different specimen geometries to provide the designer with reliable design data relevant to practical applications. Therefore, it is necessary to study the effect of strain rate, ring configuration, and grip or fixture type on the mechanical behavior of dumb-bell-shaped, (DBS), and ring specimens made from HDPE pipe material. DBS and ring specimens are cut from the pipe in longitudinally, and circumferential (transverse) direction respectively. On the other hand, the ring specimen configuration is classified into two types; full ring, (FR), and notched ring, (NR) (equal double notch from two sides of notched ring specimen) specimens according to ASTM D 2290-12 standard. Tensile tests are conducted on specimens cut out from the pipe with thickness 10 mm at different crosshead speeds (10–1000 mm/min), and ambient temperature, Ta = 20 °C to investigate the mechanical properties of DBS, and ring specimens. In the case of test specimens taken from longitudinal direction from the pipe a necking phenomenon before failure appears at different locations along the gauge section. On the other hand, the fracture of NR specimens occurs at one notched side. The results demonstrated that the NR specimen has higher yield stress than DBS, and FR specimens at all crosshead speeds. The present experimental work reveals that the crosshead speed has a significant effect on the mechanical behavior of both DBS, and ring specimens. The fixture type plays an important role in the mechanical behavior for both FR and NR specimens at all crosshead speeds.

Effect of Specimen Geometry on the Predicted Mechanical Behavior of Polyethylene Pipe Material1

2015 ◽  
Vol 137 (6) ◽  
Author(s):  
Tarek M. A. A. EL-Bagory ◽  
Tawfeeq A. R. Alkanhal ◽  
Maher Y. A. Younan
Keyword(s):  
Mechanical Behavior ◽  
Longitudinal Direction ◽  
Tensile Tests ◽  
Primary Objective ◽  
The Other ◽  
Pipe Material ◽  
Design Data ◽  
Practical Applications ◽  
Other Hand ◽  
Gauge Section

The primary objective of the present paper is to depict the mechanical behavior of high density polyethylene (HDPE) pipes under different loading conditions with different specimen geometries to provide the designer with reliable design data relevant to practical applications. Therefore, it is necessary to study the effect of strain rate, ring configuration, and grip or fixture type on the mechanical behavior of dumb-bell-shaped (DBS), and ring specimens made from HDPE pipe material. DBS and ring specimens are cut from the pipe in longitudinal and circumferential (transverse) directions, respectively. On the other hand, the ring specimen configuration is classified into two types; full ring (FR), and notched ring (NR) (equal double notch from two sides of NR specimen) specimens according to ASTM D 2290-12 standard. Tensile tests are conducted on specimens cut out from the pipe with thickness of 10 mm at different crosshead speeds (10–1000 mm/min), and ambient temperature, Ta = 20 °C to investigate the mechanical properties of DBS and ring specimens. In the case of test specimens taken from the longitudinal direction from the pipe, a necking phenomenon before failure appears at different locations along the gauge section. On the other hand, the fracture of NR specimens occurs at one notched side. The results demonstrated that the NR specimen has higher yield stress than DBS and FR specimens at all crosshead speeds. The present experimental work reveals that the crosshead speed has a significant effect on the mechanical behavior of both DBS and ring specimens. The fixture type plays an important role in the mechanical behavior for both FR and NR specimens at all crosshead speeds.

Effect of Loading Rate and Pipe Wall Thickness on the Strength and Toughness of Welded and Unwelded Polyethylene Pipes

2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Tarek M. A. A. EL-Bagory ◽  
Hossam E. M. Sallam ◽  
Maher Y. A. Younan
Keyword(s):  
Mechanical Behavior ◽  
Mechanical Characteristics ◽  
Tensile Tests ◽  
Primary Objective ◽  
Design Data ◽  
Practical Applications ◽  
Polyethylene Pipes ◽  
Gauge Section ◽  
Reliable Design ◽  
Hdpe Pipes

Abstract The primary objective of this paper is to depict the mechanical behavior of welded and unwelded high-density polyethylene (HDPE), pipes to provide the designer with reliable design data relevant to practical applications. Therefore, it is necessary to study the effect of strain rate and specimen configuration on the mechanical behavior of welded and unwelded pipes made from HDPE. Tensile tests are conducted on specimens longitudinally cut from the pipe with thickness (10 and 30 mm), at different crosshead speeds (5–500 mm/min), and different gauge lengths (20, 25, and 50 mm) to investigate the mechanical properties of welded and unwelded specimens. All tests are performed at room temperature (Ta = 23 °C). Butt fusion, BF, welding method is used to join the different parts of HDPE pipes. The present results showed that the mechanical characteristics of welded specimens are lower than those of unwelded specimens. In the case of test specimens taken from unwelded pipe, the results of mechanical characteristics revealed that a necking phenomenon before failure appears at different locations along the gauge section. On the other hand, the fracture of welded specimens almost occurs at the fusion zone. It is found that the crosshead speed and specimen configurations have a significant effect on the mechanical behavior of both welded and unwelded specimens.

Mechanical Behavior of Welded and Un-Welded Polyethylene Pipe Materials

2013 ◽  
Author(s):  
Tarek M. A. A. El-Bagory ◽  
Maher Y. A. Younan ◽  
Hossam E. M. Sallam
Keyword(s):  
Mechanical Behavior ◽  
Fusion Zone ◽  
Tensile Tests ◽  
Primary Objective ◽  
Design Data ◽  
Practical Applications ◽  
Gauge Section ◽  
Reliable Design ◽  
Welded Pipe ◽  
Hdpe Pipes

The primary objective of the present paper is to depict the mechanical behavior of high density polyethylene, HDPE, pipes to provide the designer with reliable design data relevant to practical applications. Therefore, it is necessary to study the effect of strain rate and specimen configuration on the mechanical behavior of welded and un-welded pipes made from HDPE. Tensile tests are conducted on specimens longitudinally cut from the pipe with thickness (10, and 30 mm), at different crosshead speeds (5–500 mm/min), and different gauge lengths (20, 25, and 50 mm) to investigate the mechanical properties of welded and un-welded specimens. Butt-fusion, BF, welding method is used to join the different parts of HDPE pipes. In the case of test specimens taken from un-welded pipe a necking phenomenon before failure appears at different locations along the gauge section. On the other hand, the fracture of welded specimens almost occurs at the fusion zone. At lower crosshead speeds the fracture of welded specimen occurs in all specimen configurations at the fusion zone. The present experimental work reveals that the crosshead speed has a significant effect on the mechanical behavior of both welded and un-welded specimens.

scholarly journals The Influence of Demographic and Herbal Characteristics on Purchase Decisions of Zingiberacea Familia: An Exploration in Kota Bharu, Kelantan Society

2019 ◽  
Vol 8 (2S9) ◽  
pp. 1058-1062
Keyword(s):  
World View ◽  
Secondary Data ◽  
Positive Influence ◽  
Primary Objective ◽  
The Other ◽  
Primary Data ◽  
Purchase Decision ◽  
Green Product ◽  
Other Hand ◽  
Environmentally Safe

In Malaysia, for over a decade a product of Zingibereacea familia especially ginger are coming as one of the famous product in Malaysian market. The study brings out green product from Zingiber Officianale Roscoe (Ginger) among 100 respondents in Kota Bharu, Kelantan with a primary objective to search a response from the customer’s either this product can be presumed to be environmentally safe should be preserved as a medicinal plant and commercialized within and outside the country. In regard to the fact that “Green Marketing” is developed as a products that are presumed to be environmentally safe. The objective of this research was to determine usage profiles and some variables that influence the purchase decision of herbal medicine in Kota Bharu Kelantan, and (2) to evaluate the consumer’s response on the development of Zingiberacea Familia Based Product, either it can be a symbol of herbs that can be lifted as a health and beauty product in the preservation and preservation of Malay culture. Primary data was collected from the survey tabulated within the Kota Bharu society, and secondary data was collected from the available literature sources. The core idea of the finding are a world view is also a two-way bridge: A respondent shows a positive reaction that Zingibearacea Familia product could be be a symbol of herbs that can be lifted as a health and beauty product in the preservation and preservation of Malay culture. On the other hand, only age characteristic showed significant influence on purchase decision of green product from Zingiberacea Familia, on the other hand races, level of education and job sector didn’t show positive influence

scholarly journals The limits of distribution-free conditional predictive inference

2020 ◽  
Author(s):  
Rina Foygel Barber ◽  
Emmanuel J Candès ◽  
Aaditya Ramdas ◽  
Ryan J Tibshirani
Keyword(s):  
The Other ◽  
Conditional Inference ◽  
Predictive Inference ◽  
Distribution Free ◽  
Conformal Prediction ◽  
Underlying Distribution ◽  
Practical Applications ◽  
Other Hand ◽  
Test Points ◽  
Exact Conditional Inference

Abstract We consider the problem of distribution-free predictive inference, with the goal of producing predictive coverage guarantees that hold conditionally rather than marginally. Existing methods such as conformal prediction offer marginal coverage guarantees, where predictive coverage holds on average over all possible test points, but this is not sufficient for many practical applications where we would like to know that our predictions are valid for a given individual, not merely on average over a population. On the other hand, exact conditional inference guarantees are known to be impossible without imposing assumptions on the underlying distribution. In this work, we aim to explore the space in between these two and examine what types of relaxations of the conditional coverage property would alleviate some of the practical concerns with marginal coverage guarantees while still being possible to achieve in a distribution-free setting.

Effect of Size-Dependent Cavitation on Micro- to Macroscopic Mechanical Behavior of Rubber-Blended Polymer

2008 ◽  
Vol 130 (2) ◽  
Author(s):  
Isamu Riku ◽  
Koji Mimura ◽  
Yoshihiro Tomita
Keyword(s):  
Surface Tension ◽  
Plastic Deformation ◽  
Mechanical Behavior ◽  
Volumetric Strain ◽  
Critical Value ◽  
The Other ◽  
Size Dependent ◽  
Other Hand ◽  
Blended Polymer ◽  
Onset Of Cavitation

In rubber-blended polymer, the onset of cavitation in the particles relaxes the high triaxiality stress state and suppresses the onset of crazing in the polymer. As a result, large plastic deformation is substantially promoted compared with single-phase polymer. On the other hand, it is also well known that the onset of cavitation depends on the size of particle. To investigate the size dependence of cavitation behavior in the particle, a theoretical analysis is done employing a void model under plane strain condition, which takes into account the surface tension and the limiting stretch of the void. Continuously, to study the effect of the size-dependent cavitation on the micro- to macroscopic mechanical behavior of the blend, a computational model is proposed for the blend consisting of irregularly distributed heterogeneous particles containing the void with surface force. The results indicate that when the size of the particle decreases to a critical value that depends on both the initial shear modulus of particle and the surface tension on the surface of void, the increase of the critical stress for the onset of cavitation becomes remarkable and consequently, the onset of cavitation is eliminated. When the particle is embedded in polymer, the relation between average normal stress, which is acting on the interface of particle and matrix, and volumetric strain of particle shows dependence on the size of particle but no dependence on the triaxiality of macroscopic loading condition. For the blend consisting of particles smaller than the critical value, the onset of cavitation is eliminated in particles and as a result, the conformation of the shape of particle to the localized shear band in matrix becomes difficult and the shear deformation behavior tends to occur all over the matrix. Furthermore, in this case, the area of the maximum mean stress is confined to the area adjacent to the particle and the value of it increases almost linearly throughout the whole deformation process, which would lead to the onset of crazing in matrix. On the other hand, it is clarified that the onset of cavitation is predominant in the localized microscopic region containing heterogeneous particles and therefore, the plastic deformation is promoted in this region.

scholarly journals The Impact of Labor Mobility on Living Standard: an Empirical Study on the Northern Region of Bangladesh

2021 ◽  
Vol 10 (1) ◽  
pp. xx-xx
Author(s):  
Omar Faruque
Keyword(s):  
Global Economy ◽  
Labor Mobility ◽  
Northern Region ◽  
Primary Objective ◽  
The Other ◽  
Primary Data ◽  
Living Standard ◽  
Other Hand ◽  
The People ◽  
The Impact

In the past 10 years, Bangladesh has experienced positive economic and social changes.  Historically, labor mobility has been a common livelihood strategy of the people as well as the Bangladeshi people. Labor mobility has become an integral part of the current global economy. The primary objective of this study is to provide a review of the impact of labor mobility on living standards in the northern region of Bangladesh. To develop the paper, primary as well as secondary data are collected. The quantitative, as well as qualitative analyses, are conducted in this study. Primary data is collected through a set of well-structured questionnaires. In the study, it is observed that there is 8% of labor are migrated within the last three years. From 2011 to 2015, the maximum laborers are migrated i.e., 37% and 33% migrated labor were day labor.  There are 35.56% of people with zero income level per day before their migration. On the other hand, after the migration, there are no people with nil income. Before the migration, 81.11% of people incur their expenditure for buying the inferior goods and the rest of the people incur for the necessary goods, but no one can consume the luxurious goods. On the other hand, after the migration, only 4.44% of laborers are availing of luxurious goods. So still they are not enjoying their life. Before the migration, they are 9% of people who are extremely dissatisfied with these types of facilities, and 33.33% of people were very dissatisfied. On the other hand, there are 23.33% of laborers are very pleased with their medical facilities, shelter, and child education facilities. The result shows that 41% of people are pushed for migration. It is assumed that there is a great impact of labor mobilization on the living standard. The labor is migrated in order to have a better living standard. There are two alternatives for their survival, first, we have to provide job opportunities near their residence, and the alternative is to provide a better living standard for the migrated people.

scholarly journals Chatbot and its Practical Applications in the Materialistic World

2019 ◽  
Vol 8 (4) ◽  
pp. 4459-4463
Keyword(s):  
Artificial Intelligence ◽  
Machine Learning ◽  
Industrial Revolution ◽  
Gradual Increase ◽  
The Other ◽  
Way Of Life ◽  
Practical Applications ◽  
Other Hand ◽  
The World ◽  
Different Types

These days Chat has become the new way of conversation and changed the way of life and the view that the world used to see before and due to Industrial revolution 4.0 , the gradual increase in machine learning and artificial intelligence fields has gone to higher and many companies are reaching customers to get their products with more ease . This is where chatbots are used. It all started with one question! can machines think? The concept of chatbots came into existence to check whether the machines could fool users and make them think that they are actually talking to humans and not robots. On the Other hand, with the Successes Rate of Chat bots, Different companies Started using machines for having conversations with their customers about everything which made their work simpler and reduced the need of man power. There are many different types of building a chatbot but this paper will mainly concentrate on building a Chatbot using TensorFlow API in python

scholarly journals PRINCIPAIS DESAFIOS DAS CIDADES BRASILEIRAS E ALTERNATIVAS OPORTUNIZADAS PELA INTERNET DAS COISAS

2020 ◽  
Vol 11 (1) ◽  
pp. 39-51
Author(s):  
Deuzilene Braga Santana ◽  
Vivianni Marques Leite dos Santos
Keyword(s):  
Decision Making ◽  
Internet Of Things ◽  
Electronic Devices ◽  
The Other ◽  
The Internet ◽  
Systematic Mapping ◽  
Practical Applications ◽  
Other Hand ◽  
The Internet Of Things ◽  
Internet Network

The Internet of Things (IoT) is a technology that encompasses electronic devices that have embedded technologies, sensors and connection to the Internet network, capable of collecting, processing, transmitting data and sharing information among each other, in order to transform data into information for decision making. On the other hand, there are still urban challenges facing cities where IoT can contribute. Aiming to support this theme, this study developed a systematic mapping of the literature on IoT and the main challenges faced by Brazilian cities, pointing out existing initiatives and alternatives of how IoT can help to solve them. The results showed evidence of practical applications on the use of IoT as a solution to the challenges in the cities. In addition, these results suggest the feasibility of using IoT in the solution of these problems.  

Linear Thermal Expansion of Elastomers in the Range 300° to 76° K

1964 ◽  
Vol 37 (1) ◽  
pp. 154-168 ◽  
Author(s):  
R. F. Robbins ◽  
Y. Ohori ◽  
D. H. Weitzel
Keyword(s):  
Thermal Expansion ◽  
Linear Thermal Expansion ◽  
The Other ◽  
Thermal Contraction ◽  
Cryogenic Temperatures ◽  
Design Data ◽  
Polar Groups ◽  
Other Hand ◽  
Commercial Sources ◽  
Ceramic Fillers

Abstract From the relations between Tg's of the component homopolymers with that of the resulting copolymer, one sees that the limit of the Tg of copolymers is that of the homopolymers. To obtain a low Tg one must avoid polymers with polar groups and/or bulky groups. Polar groups afford opportunities for intermolecular links which hinder rotation necessary for “rubberyness.” Bulky groups cause stiffness, and also serve as obstructions to contractions. On the other hand, the same reasons that polar and bulky groups raise Tg serve to lower overall thermal contraction, since αr is always greater than αg. Fillers can be used to lower contraction, and new ceramic fillers with negative coefficients of expansion might be combined with specific polymers to obtain a material with a desired contraction. The authors feel that the data presented here, together with design data available from commercial sources, should enable the design engineer to find many new uses for elastomers at cryogenic temperatures.

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