This article discusses the design of a reinforced thermoplastic pipe (RTP) with a mesh frame and provides an overview of analytical methods for determining the stresses arising in these pipes under the action of internal pressure. It is necessary to determine the stresses arising in the RTP in order to assess the strength of the structure and the loads allowed for it. The purpose of this work is to evaluate the accuracy of analytical methods describing the stress-strain state of pipes. For this, an experimental study was carried out to determine the breaking pressure and mechanical properties of materials (Young's modulus, Poisson's ratio, coefficient of linear thermal expansion, yield stress and ultimate strength). Since all the considered analytical methods are intended to describe the stress-strain state of pipes in the elastic deformation zone, it would be incorrect to use directly the data obtained in the course of the experimental study. In this regard, based on the obtained experimental data, numerical models were built and adapted in the ANSYS software package. The condition for the destruction of the numerical model was the achievement of the equivalent stresses calculated according to Mises (energy (fourth) theory of strength), the ultimate strength in at least one of the materials of the structure. Then, using the adapted models by the finite element method, the stresses arising from the action of a lower internal pressure and not exceeding the yield strength of the materials were calculated. Based on the results obtained, an analysis of analytical methods was carried out and conclusions were drawn about the possibility of their application to describe the stress-strain state of a RTP with a mesh frame.
References
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