DESIGNING AND DETAILING OF BUILDING SYSTEMS. MECHANICS IN CIVIL ENGINEERING

Problematics of stress-strain state research in units of metal structures

Vestnik MGSU 5/2014
  • Morozova Dina Vol'demarovna - Moscow State University of Civil Engineering (MGSU) Candidate of Technical Sciences, Associate Professor, Senior Researcher, Department of Architectural and Structural Design, Moscow State University of Civil Engineering (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .
  • Serova Elena Aleksandrovna - Moscow State University of Civil Engineering (MGSU) postgraduate student, Department of Architectural and Structural Design, Moscow State University of Civil Engineering (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Pages 44-50

The article describes the experimental methods of determining stress-strain state of elements and structures with a brief description of the essence of each method. The authors focus mostly on polarization-optical method for determining stresses in the translucent optical sensing models made of epoxy resins. Physical component of the method is described in the article and a simple diagram of a circular polariscope is presented, as well as an example of the resulting interference pattern in illuminated monochromatic light. A polariscope, in its most general definition, consists of two polarizers. The polarizers sandwich a material or object of interest, and allows one to view the changes of the polarity of light passing through the material or object. Since we are unable to perceive the polarity of light with the naked eye, we are forced to use polariscopes to view the changes in polarity caused by the temporary birefringence of our photoelastic materials. A polariscope is constructed of two polarizers, each set perpendicular to the path of light transmitted through the setup. The first polarizer is called the "polarizer", and the second polarizer is called the "analyzer". The method how the polarizer works is quite simple: unpolarized light enters the polariscope through the polarizer, which allows through only the light of its orientation. This light then passes through the material under observation, and experiences some change in polarity. Finally, this light reaches the analyzer, which, like the polarizer, only lets the light of its orientation through.

DOI: 10.22227/1997-0935.2014.5.44-50

References
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Analysis of stress-strain state on top of a rectangular wedge

Vestnik MGSU 5/2014
  • Frishter Lyudmila Yur'evna - Moscow State University of Civil Engineering (MGSU) Doctor of Technical Sciences, Professor, Chair, Department of Higher Mathematic, Moscow State University of Civil Engineering (MGSU), 26 Yaroslavskoe Shosse, Moscow, 129337, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Pages 57-62

Modeling singular solutions of the elasticity theory problems, which are determined by geometric factor - bird's mouth of the edge, make it necessary to analyze the solutions with some peculiarity, which are obtained experimentally with the help of photoelasticity method. In this article the peculiar stress-strain state is analyzed on the example of the known experimental solutions for a wedge under a concentrated force obtained by M. Frocht. Solution analysis for a wedge with a power-type peculiarity obtained experimentally by photoelasticity method, helps to detach a singular solution field, where fringe contour is not visible. Due to idealization of the boundary shape and loading technique, infinitely large stresses arise, which are obtained as a singular solution of the boundary problem in a planar domain. Comparison of theoretical and experimental solutions obtained for a wedge shows areas of overlap and areas of significant and insignificant differences as a result of the inability to experimentally apply the force to a single point.

DOI: 10.22227/1997-0935.2014.5.57-62

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  11. Frishter L.Yu. O vozmozhnostyakh polucheniya metodom fotouprugosti napryazhennogo sostoyaniya v oblasti kontsentratsii napryazheniy [On the Possibilities to Obtain Stress State in the Area of Stress Concentration by the Photoelasticity Method]. Vestnik MGSU [Proceedings of Moscow State University of Civil Engineering]. 2008, no. 1, pp. 165—168.
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