Calibration testing of discs using photoelasticity method

Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow, 129337, Russia

^* Corresponding author: lfrishter@mail.ru

Abstract

Using of the photoelasticity method for determining the stresses under the action of specified forced deformations and, in particular, temperature deformations, which do not satisfy the compatibility conditions, is relevant in the study of composite structures. Photoelasticity method, which is a continual method, and the method of “defrosting” forced deformations, as its subsection, allow obtaining a stress-strain state in the composite area with forced deformations on models made of optically - responsive material. The method of defrosting forced deformations, using the procedure of preliminary freezing of model elements with subsequent defrosting of the entire model, is an effective, versatile and promising method for simulation of stresses as a result of specified forced deformations. In the study of composite structures by the method of photoelasticity and defrosting “defrosting” of forced deformations, a model composed of elements with previously created forced deformations is created. To determine the created forced deformations, calibration tests are performed, in which the following actual loads are determined: forced deformations, pressure, optical and mechanical characteristics of the model material: modulus of elasticity, material fringe value. Novelty of the calibration test method is the definition of “frozen” forced deformations in the blank of the photoelasticity model using a single composite disk model without testing additional models - beams [1, 2]. Taken into account the material parameters of model: Young's modulus, the price of a polymeric material strip, which are different for batches of initial components: epoxy resin and anhydrite. In order to approve the results of calibration tests, this paper considers the theoretical and experimental solution of the elasticity test problem for a composite disk, one of the areas of which is uniformly heated. The obtained data are used for calibration tests in determining the actual loads and mechanical characteristics in the model sections.