Description of Cyclic Properties of Steel in Variability Conditions of Mean Values and Amplitudes of Loading Cycles

2012 ◽  
Vol 726 ◽  
pp. 69-76 ◽  
Author(s):  
Grzegorz Szala ◽  
Bogdan Ligaj
Keyword(s):  
Mechanical Properties ◽  
Mathematical Models ◽  
Experimental Test ◽  
Point Of View ◽  
Test Results ◽  
Mean Values ◽  
Fatigue Characteristics ◽  
Verification Test

The work includes description of determination of two-parametric fatigue characteristics (TFC) on the base of experimental test results and description of mathematical models of these characteristics. Mathematical models were verified in C45 and 41Cr4 tests that are essentially different from the point of view of mechanical properties. On the base of analysis of verification test results there were determined ranges of applications of TFC models described in the work.

Behaviors of Xiashu Loess in the Lower Reaches of China’s Yangtze River under Triaxial Compression and the Microscopic Explanations

2016 ◽  
Vol 858 ◽  
pp. 91-97
Author(s):  
Jun Hua Xiao ◽  
Wen Qi Zheng
Keyword(s):  
Mechanical Properties ◽  
Yangtze River ◽  
Shear Failure ◽  
Triaxial Compression ◽  
Processing Technique ◽  
Point Of View ◽  
Image Processing Technique ◽  
Test Results ◽  
Compression Tests ◽  
Triaxial Compression Tests

To investigate the macroscopic mechanical properties of undisturbed structural Xiashu loess in the lower reaches of China’s Yangtze River under triaxial compression, and obtain the intrinsic explanations for the macroscopic mechanical properties from the microscopic point of view, in laboratory, triaxial compression tests were carried out, microstructure images of sheared samples were collected by scanning electron microscope (SEM), and quantitative parameters of microstructure (mainly about particle or pore size, distribution, and alignment) were extracted by digital image processing technique. Based on the test results, the deviator stress-strain relationships of both undisturbed and remoulded Xiashu loess, the structural strength, and the microstructural evolution mechanism about the formation of shear failure zone of Xiashu loess under triaxial compression were analyzed.

scholarly journals Empirical determination of the mechanical properties of Vacuum Packed Particles

2019 ◽  
Vol 254 ◽  
pp. 05008 ◽  
Author(s):  
Piotr Bartkowski ◽  
Robert Zalewski
Keyword(s):  
Mechanical Properties ◽  
Numerical Model ◽  
Model Validation ◽  
Experimental Test ◽  
Empirical Determination ◽  
Validation Procedure

In this work the experimental test of Vacuum Packed Particles (VPP) under 3-point bending are presented. VPP it is the structure compose of grains inside the plastomer coating. When the pressure inside is equal or higher than zero structure behave like a liquid, otherwise like a elasto-plastic solid. Three types of grain material and different values of underpressure were tested. Results presented in this paper will be used in the further work for the numerical model validation procedure.

scholarly journals Electrochemical Determination of Sudan Dyes and Two Manner to Realize it: a Theoretical Investigation

2020 ◽  
Vol 9 (4) ◽  
pp. 1451-1458
Keyword(s):  
Mathematical Models ◽  
Bifurcation Analysis ◽  
Stability Theory ◽  
Electrochemical Determination ◽  
Theoretical Description ◽  
Point Of View ◽  
Linear Stability Theory ◽  
Sudan Dyes ◽  
Monotonic Instability

In this work, a general theoretical description of the electrochemical determination of Sudan dyes by cathodic and anodic route has been made. Two mathematical models have been developed for each case, being, afterward, analyzed by means of linear stability theory and bifurcation analysis. It has been shown that in both cases, the systems are efficient from the electroanalytical point of view. The possibility for the oscillatory and monotonic instability has also been verified.

scholarly journals Determination of Mechanical Properties of Rubberized Concrete in Marine Environment

2019 ◽  
Vol 8 (2) ◽  
pp. 5761-5765
Keyword(s):  
Mechanical Properties ◽  
Fly Ash ◽  
Marine Environment ◽  
Concrete Specimen ◽  
Crumb Rubber ◽  
Fine Aggregate ◽  
Test Results ◽  
Rubberized Concrete ◽  
Split Tensile Strength

With an objective of saving the environment by providing crumb rubber as an alternative to natural fine aggregate this paper presents a study carried out to find the mechanical properties of rubberized concrete. Rubberized concrete is made up of waste rubber from vehicle tyres and other rubber waste which otherwise is left out polluting the environment. In this paper, 7.5% of crumb rubber (obtained by shredding the vehicle tyres) as an alternative to fine aggregate and 7.5% of fly-ash as an alternative to cement is added with other ingredients of concrete to produce an eco-friendly concrete which can be used economically and effectively for construction along the coastal areas. Various properties like workability, compressive strength, split tensile strength, and flexural strength was carried out on concrete specimens exposed to the natural marine environment along the coast of Visakhapatnam, Andhra Pradesh. The total exposure of concrete specimen was about 150 days, and various specimens were tested at 7, 28, 90, 120 and 150 days, respectively. The test results showed that with a slight compromise in strength, the workability of concrete and resistance to the effect of seawater on the strength of concrete significantly improved with the addition of crumb rubber and fly-ash.

scholarly journals Investigation on the Mechanical Properties of Fiber Reinforced Recycled Concrete

2016 ◽  
Vol 2 (1) ◽  
pp. 13-22 ◽  
Author(s):  
Hasan Jalilifar ◽  
Fatholla Sajedi ◽  
Sadegh Kazemi
Keyword(s):  
Mechanical Properties ◽  
Flexural Strength ◽  
Experimental Test ◽  
Fiber Volume Fraction ◽  
Volume Fraction ◽  
Fiber Content ◽  
Recycled Concrete ◽  
Test Results ◽  
Fiber Volume ◽  
Flexural Toughness

The flexural strength of conventional concrete material is known to be enhanced by incorporating a moderate volume-fraction of randomly distributed fibers. However, there is limited information on describing the influence of fiber volume-fraction on the compressive and flexural strength of recycled coarse aggregate concrete (RCA-C) material. This paper reports on experimental test results of the RCA-C material replaced with 0, 30, 50 and 100% recycled aggregate and 0, 0.5, 1 and 1.5% steel fiber volume fraction. Three-point flexural tests of notched prism specimens were completed. The mechanical properties in compression were characterized using cube specimens. Significant improvement in compressive and flexural strength of RCA-C was found as fiber content increased from 0 to 1.5%. The experimental test results of RCA-C were further evaluated to investigate the influence of fiber content on flexural toughness. According to test results, the addition of steel fibers to RCA-C material appreciably increased the flexural toughness.

scholarly journals Laboratory determination of hydraulic anisotropy of dense graded asphalt concrete

2018 ◽  
Vol 38 (1) ◽  
pp. 67-73 ◽  
Author(s):  
Alberto Gaxiola-Hernández
Keyword(s):  
Asphalt Concrete ◽  
Asphalt Mixture ◽  
Point Of View ◽  
Design Stage ◽  
Test Results ◽  
Test Device ◽  
Hydraulic Anisotropy ◽  
Vehicle Loads ◽  
Constant Head

Dense graded asphalt concrete is widely used in roads as support structure for vehicle loads, however, is also used for hydraulic purposes in canal linings as well as faces and cores of dams. In the design stage of these constructions it is necessary to have the permeability data of the materials that will be used and, although in some cases it is sufficient to know this parameter in only one direction, in others it is necessary to have it in two directions. This research presents test results of axial permeability in constant head permeameter and the design a of radial permeability test device in asphalt concrete made for hydraulic purposes. As a result it was determined that the compaction process of asphalt concrete, applied in one direction, causes the material to have anisotropic behavior from the hydraulic point of view, resulting in anisotropy ratios 7.1 to 10.4, for the studied asphalt mixture.

Particleboard Manufactured with Variation of Press Time

2015 ◽  
Vol 1088 ◽  
pp. 644-647
Author(s):  
Cristiane Inácio de Campos ◽  
Bruno Santos Ferreira ◽  
André Luis Christoforo ◽  
Francisco Antonio Rocco Lahr ◽  
Juliana Cortez Barbosa ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Physical And Mechanical Properties ◽  
Mechanical Tests ◽  
Modulus Of Rupture ◽  
Test Results ◽  
Thickness Swelling ◽  
Mean Values ◽  
Tukey Test ◽  
Press Time ◽  
Brazilian Standard

This research aimed to produce and determine physical and mechanical properties of three-layered particleboard produced with Pinussp. wood particlesand three different times of press, i.e., 3, 5 and 7 minutes. Recommendations of the Brazilian standard ABNT NBR 14810 [1] were adopted to fundament physical and mechanical tests. The properties evaluated were the modulus of rupture (MOR) and modulus of elasticity (MOE) in static bending; internal bond; thickness swelling; water absorption; moisture content and apparent density.The mean values showed, for the physical properties, that all the panels manufactured achievedthe requirements of theBrazilian standard, and for mechanical properties, only the panelsmanufacturedwith 7minutesofpressing timemet therequirements. From the Tukey test results, timesof the pressingcycleinfluencedsignificantlyin allinvestigatedphysical and mechanicalproperties, showed better results the panels madewithseven minutesof the pressingcycle, implyingthat the time ofseven minutesof the pressingcycle is thebest among theinvestigatedperiodsin the manufactureofparticleboard.

scholarly journals Determination of emission of iron oxides from the welding process on the basis of mathematical models

2021 ◽  
Vol 93 (2) ◽  
pp. 35-42
Author(s):  
Jarosław Mikołajczyk ◽  
Karolina Pikulik
Keyword(s):  
Mathematical Models ◽  
Iron Oxides ◽  
Welding Process ◽  
Welding Current ◽  
Test Results ◽  
Negative Effects ◽  
Average Value ◽  
Harmful Emission ◽  
R Program

Oxygen in metals is most often present in the form of oxides, including: FeO, Fe2O3, Fe3O4. The complexity of the welding process means that oxygen compounds can enter both the liquid metal and the atmosphere, causing negative effects. A welder is exposed to harmful emission of oxides entering the human body through the respiratory system or pores in the skin. The essence of the problem is so serious that standards for air purity and determination of amount of oxides at workplaces have been introduced. The article presents the results of research on the influence of the welding current intensity on the emission of air pollutants (in particular the emission of iron oxides) of the inhalable and respirable fractions. The bench tests were carried out on the basis of the applicable standards for air quality at welding stations. Based on the test results, on the basis of the R program, mathematical models of the emission of iron oxides generated during the welding process were developed. It was observed that with the increase of the welding current, the average value of the emission of iron oxides – both the inhalable and respirable fractions – increases. For both fractions, it was also noted that the model values ​​are closer to the values measured in the model No. 1.

scholarly journals Anthropogenetic variability in the groups of homo- and heterosexually oriented individuals

Genetika ◽  
2015 ◽  
Vol 47 (2) ◽  
pp. 765-776
Author(s):  
Suzana Cvjeticanin
Keyword(s):  
Genetic Variability ◽  
Population Genetic ◽  
Control Group ◽  
Population Genetic Study ◽  
Test Results ◽  
Mean Values ◽  
Significant Difference ◽  
The Mean ◽  
Distribution Type

This population-genetic study compares morphophysiological and genetic variability in a group of homosexually oriented individuals from Serbia (N=96) with control group of heterosexual individuals (N=96) using a test of determination of homozygously recessive characteristics in humans (HRC-test). Results of our study revealed a statistically significant difference in the mean values of genetic homozygosity (control group 5.0+0.2 ; homosexuals 3.4 +0.1 HRCs, out of 20 observed characteristics) the differences in the distribution type, as well as in the variances of presence of specific combinations of such traits. These results suggest a complex polygenic difference between two observed systems. There is no difference in the degree of genetic homozygosity between the genders in each tested group of individuals. However, both homosexually oriented females and males have significantly lower mean values of HRCs compared to female and male heterosexuals.

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