eng
Pouyan Press
Computational Engineering and Physical Modeling
2588-6959
2019-04-01
2
2
1
14
10.22115/cepm.2019.127447.1025
95952
مقاله پژوهشی
Approaches in the development of motion sensors in the dynamics of granular media
Andrey Eliseev
eavsh@ya.ru
1
A.S. Mironov
2
S.V. Eliseev
3
Irkutsk State Transport University, 15 Chernyshevsky St., Irkutsk, 664074, Russia
Irkutsk State Transport University, 15 Chernyshevsky St., Irkutsk, 664074, Russia
Irkutsk State Transport University, 15 Chernyshevsky St., Irkutsk, 664074, Russia
For the processes implemented in the technologies of vibrational strengthening of parts, it is necessary to develop options and justify the constructive and technical schemes of measuring devices that react to the existence of special modes of interaction of the granular working medium with a vibrating surface. Development of methodological positions for the development of measuring devices for evaluating the properties of the vibrational fields of technological machines. Three directions of construction of measuring devices are considered. A signal carrying useful information is formed by changing the sound pressure in the capsule with the microphone. The variants of constructive implementation of schemes for measuring the parameters of the vibrational field are considered. The article uses analytical approaches to the theory of vibrational displacements; it proposes and studies modes with a continuous tossing and the time of approach of the medium element, multiple to the period of the oscillation of the support surface. When processing experimental results, statistical analysis methods are used. A technique for processing the sensor signal is developed and proposed with the use of programs of analysis and detection of regularities. It is shown that the processes of interaction with a continuous tossing have properties that can be reflected in the forms of self-organization of the movement of the elements of the measuring device. The article presents the results of experiments.
https://www.jcepm.com/article_95952_84e18b39f8f08e7a700ab469aa9ba8f8.pdf
mechanical system
vibrational interaction
vibrating field
Sensor
eng
Pouyan Press
Computational Engineering and Physical Modeling
2588-6959
2019-04-01
2
2
15
24
10.22115/cepm.2019.186146.1064
95951
Using Pressuremeter Test Results to Estimate Bearing Capacity in the Vicinity of a Slope- Numerical Analysis-
Ouabel Houari
ouabelhouari@yahoo.fr
1
Department of Civil Engineering, Faculty of Technology, University of Tlemcen, Algeria
This work consists in using the results of the modeling of the pressuremeter test in the estimation of the bearing capacity near a slope, the proposed basic formulas correspond to a simple configuration of reference, the soil mass being on surface free horizontal and the foundation subjected to a vertically centered load. The most complex cases, and in particular the presence of a slope, are treated by means of reducing coefficients applied to the basic formulas. The main objective of this article is to estimate numerically the characteristics of the pressuremeter test (pressure limit, pressuremeter module) to determine the bearing capacity in the vicinity of a slope. Our contribution is therefore to use a calculation code based on the element method with the contribution of two elasto-plastic laws, namely Mohr-Coulomb and Cam-Clay), with the exploitation of the results of the geotechnical survey carried out. as part of the project on the railway line in the Tissesmilt region (west of Algeria) and finally test the reliability of the results with the use of a statistical study by the approach of the normal law (probabilistic method).
https://www.jcepm.com/article_95951_3a8616da612799ae4d86b5a480a5d8aa.pdf
Pressuremeter test
Bearing Capacity
Slope
Mohr-Coulomb
Cam-Clay
Normal law
eng
Pouyan Press
Computational Engineering and Physical Modeling
2588-6959
2019-04-01
2
2
25
35
10.22115/cepm.2019.159164.1053
96018
مقاله پژوهشی
Design Formula at Ultimate Stresses for Ekki (Lophira Alata) Timber Beam
Jimoh Abdullahi Alao
aajimoh4real@yahoo.com
1
Department of Civil Engineering, University of Ilorin, Ilorin, Nigeria
The global pursuance of design method for economic utilization of building material is the basis of this study. The ultimate stress design method proposed in this study is in line with this pursuit as it encourages full utilization of material section and thus brings in economy in material application. This is the focus of this study on appropriate design procedure for Ekki (Lophira alata ) timber beam. This new method can replace the conventional design which is based only on modulus of rupture that has been reported not a rational method because it relies only on the extreme thin fibre tensile strength of the beam in flexure, whereas, for such a beam, it is subjected to both tension stress (below the neutral axis ) and compression stress (above the neutral axis). Based on this fact, the method generated two stress expressions, one for axial tension and the other for axial compression, represented by their typical stress-strain equations for loaded Ekki specimens. To develop the beam design equations, the axial typical stress-strain equations were converted to bending expressions of the stress-neutral axis depth relationships for the Ekki beam section. These relationships were further simplified and tested to give theoretical results that compare well with the experimental values.
https://www.jcepm.com/article_96018_d684917d910874805e0a3081b30f3c53.pdf
Typical stress-strain equation
moment of resistance
ultimate tensile stress
ultimate compressive stress
Design equation
eng
Pouyan Press
Computational Engineering and Physical Modeling
2588-6959
2019-04-01
2
2
36
48
10.22115/cepm.2019.183201.1062
96306
Study on Natural Frequency of Frame Structures
Ayesha Siddika
a.siddika@unsw.edu.au
1
Md. Robiul Awall
robi95@gmail.com
2
Md. Abdullah Al Mamun
mamun_05ce7@yahoo.com
3
Tasnuva Humyra
anny030114@yahoo.com
4
Department of Civil Engineering, Pabna University of Science & Technology (PUST), Pabna-6600, Bangladesh
Department of Civil Engineering, Rajshahi University of Engineering & Technology (RUET), Rajshahi-6204, Bangladesh
Department of Civil Engineering, Rajshahi University of Engineering & Technology (RUET), Rajshahi-6204, Bangladesh
Department of Civil Engineering, Rajshahi University of Engineering & Technology (RUET), Rajshahi-6204, Bangladesh
Moment resisting frame (MRF) structures are gaining popularity for their high lateral stiffness. This study investigates the parameters which affecting the natural frequency of moment resisting frame structures. Steel and concrete MRF structures were studied theoretically, analyzed numerically to obtain their mode shapes and frequency of vibration for each mode. From the theoretical and analytical results, a model equation for approximation of natural frequency of these types of MRF structures is proposed. The proposed model expressed the relationship of natural frequency of MRF structure with its total mass, lateral dimension in the direction of vibration and total height. The proposed equation will be helpful and easy to calculate the fundamental frequency for study on dynamic behavior of structures. Comparison between the current guidelines and proposed model is also discussed. The proposed model is satisfying the general concept of free vibrational response, and can be applied for analyzing small and full scale structures.
https://www.jcepm.com/article_96306_8250cbdf916db84beda8fbb9b0454ba8.pdf
Natural frequency
Free vibration
stiffness
Mass
eng
Pouyan Press
Computational Engineering and Physical Modeling
2588-6959
2019-04-01
2
2
49
61
10.22115/cepm.2019.193015.1065
96442
مقاله پژوهشی
Time-Frequency Localization of Earthquake Record by Continuous Wavelet Transforms
Khosro Kiyani
ali3821196@yahoo.com
1
Jalil Raeisi
jalilraeisidehkordi@gmail.com
2
Ali Heidari
heidari@eng.sku.ac.ir
3
Department of Civil Engineering, Islamic Azad University Shahrekord Branch, Shahrekord, Iran
Department of Civil Engineering, Shahrekord University, Shahrekord, Iran
Department of Civil Engineering, Shahrekord University, Shahrekord, Iran
Wavelet analysis is a new mathematical method and has been increasingly applied in engineering in recent years. Unlike Fourier transform, this method is particularly appropriate for non-stationary processes. Exceptional localization can be allowed using wavelet transform, both in time and frequency domains. Wavelet transform has been rarely used in earthquake engineering. A preliminary study of continuous wavelet transforms (CWTs) was conducted in this paper. As a rather novel technique, CWT application has generated enormous interest in recent years. It has been successfully employed in many fields, including the theories of communication and ordinary, partial differential equations, signal and image processing, and numerical analysis. As evidenced, exceptional localizations of time-frequency domains have become possible through CWTs. In this paper, CWT capability of providing a full time-frequency representation of an earthquake record was demonstrated. The Morlet mother wavelet was utilized to calculate the time-frequency localization of the desired earthquake records. In this method, the time series of the earthquake records, which were broken in a wave flume, demonstrated the ability of the wavelet transform technique in detecting the complex variabilities of signals in the time-frequency domain. In this investigation, various spectral representations resulting from the CWTs were discussed and their applications for earthquake records were shown.
https://www.jcepm.com/article_96442_481fec1282d99a696f901c7063f129c6.pdf
earthquake record
time-frequency
Localization
time series
continuous wavelet transform