Summary This paper presents the experimental results of strain measurements made by the fiber Bragg grating sensors embedded into polymer composite materials (PCMs). A series of performed experiments are described to demonstrate the capability of fiber optic sensors to measure strains in the case of their pronounced gradient distribution within the material, under compression and tension, at cyclic variation of strains with time and at different temperatures. A measuring technique is presented, and the results of strain measurements during the process of preparation of PCM including measurements of residual process‐induced strains are discussed.The results of strain measurements made by fiber optic strain sensors (FOSS) are compared with the results of numerical modeling based on the finite element method and independent measurement data obtained with the use of a digital optical system Vic‐3D and other experimental devices. The comparison made shows good agreement between the results obtained by the experimental methods and numerical simulation.The results of numerical computations demonstrate that the embedment of optical fibers in a PCM introduces perturbations in the strain distribution pattern in the vicinity of optical fibers but practically does not cause changes in the value of the strain tensor component measured by the FOSS. The conclusions about applicability range of FOSS embedded into PCM were made based upon the numerical simulation. The interrelation model between Bragg wavelength peak shift and the strain of the optical fiber in the fiber Bragg grating area for the sensor that is not affected by the environment is proposed.

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Aging of composites is a pervasive problem that leads to mechanical properties degradation, reduced design life of a structure and premature accidental failure. The work is devoted to an experimental study of the preliminary temperature aging effect on the residual mechanical properties of structural CFRP. The joint use of test systems and systems for registration and analysis of acoustic emission signals was applied. The Short Beam Shear Test of CFRP specimens were carried out using the short beam method. The tests were carried out on universal electromechanical systems Instron 5882 and Instron 5965 in accordance with the recommendations of ASTM D2344. In the process of loading the samples were continuously recorded by using the acoustic emission signals system AMSY-6. A piezoelectric sensor with a frequency range of 300-800 kHz was used. The test and diagnostic systems were synchronized during the tests. In the course of the work the values of the interlayer shear strength were determined for the samples of CFRP. Typical types of the sample destruction are illustrated. When analyzing the change in the mechanical properties of the carbon fiber reinforced plastic from a temperature increase the critical values of temperatures were established in which a sharp decline in the strength and elastic characteristics of materials occurs due to an active destruction of the binder. The graphs of the energy parameter dependence and frequency characteristics of acoustic emission signals on time have been constructed and analyzed. The estimate of the processes of damage accumulation in composites is carried out. The change of the damage accumulation mechanisms was illustrated. The obtained results illustrate the effect of elevated temperatures and the duration of their impact on the mechanical behavior of structural CFRP specimens during the static tests for the interlayer shear.

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Ʌɨɛɚɧɨɜ Ⱦ.ɋ., ȼɢɥɶɞɟɦɚɧ ȼ.ɗ., ɋɩɚɫɤɨɜɚ ȿ.Ɇ., ɑɢɯɚɱɟɜ Ⱥ.ɂ. ɗɤɫɩɟɪɢɦɟɧɬɚɥɶɧɨɟ ɢɫɫɥɟɞɨɜɚɧɢɟ ɜɥɢɹɧɢɹ ɞɟɮɟɤɬɨɜ ɧɚ ɩɪɨɱɧɨɫɬɶ ɤɨɦɩɨɡɢɬɧɵɯ ɩɚɧɟɥɟɣ ɦɟɬɨɞɚɦɢ ɤɨɪɪɟɥɹɰɢɢ ɰɢɮɪɨɜɵɯ ɢɡɨɛɪɚɠɟɧɢɣ ɢ ɢɧɮɪɚɤɪɚɫɧɨɣ ɬɟɪɦɨɝɪɚɮɢɢ // ȼɟɫɬɧɢɤ ɉɟɪɦɫɤɨɝɨ ɧɚɰɢɨɧɚɥɶɧɨɝɨ ɢɫɫɥɟɞɨɜɚɬɟɥɶɫɤɨɝɨ ɩɨɥɢɬɟɯɧɢɱɟɫɤɨɝɨ ɭɧɢɜɟɪɫɢɬɟɬɚ. Ɇɟɯɚɧɢɤɚ. -2015Ɇɟɯɚɧɢɤɚ. - . -ʋ 4. -ɋ. 159-170. DOI: 10.15593/perm.mech/2015 Lobanov D.S., Wildemann V.E., Spaskova E. M., Chikhachev A.I. Experimental investigation of the defects influence on the composites sandwich panels strength with use digital image correlation and infrared thermography methods. PNRPU Mechanics Bulletin. 2015. No. 4. Pɪ. 159-170. DOI: 10.15593/perm.mech/2015 ɋɬɚɬɶɹ ɩɨɫɜɹɳɟɧɚ ɷɤɫɩɟɪɢɦɟɧɬɚɥɶɧɨɦɭ ɢɫɫɥɟɞɨɜɚɧɢɸ ɜɥɢɹɧɢɹ ɞɟɮɟɤɬɨɜ ɧɚ ɨɫɬɚɬɨɱɧɭɸ ɩɪɨɱɧɨɫɬɶ ɤɨɧɫɬɪɭɤɰɢɣ ɢɡ ɤɨɦɩɨɡɢɰɢɨɧɧɵɯ ɦɚɬɟɪɢɚɥɨɜ, ɚ ɬɚɤɠɟ ɜɨɡ-ɦɨɠɧɨɫɬɢ ɩɪɢɦɟɧɟɧɢɹ ɥɨɤɚɥɶɧɵɯ ɪɟɦɨɧɬɧɨ-ɜɨɫɫɬɚɧɨɜɢɬɟɥɶɧɵɯ ɨɩɟɪɚɰɢɣ.Ɉɛɴɟɤɬɚɦɢ ɢɫɫɥɟɞɨɜɚɧɢɹ ɹɜɥɹɸɬɫɹ ɤɨɧɫɬɪɭɤɬɢɜɧɨ-ɩɨɞɨɛɧɵɟ ɷɥɟɦɟɧɬɵ, ɨɛɪɚɡɰɵ ɡɜɭɤɨɩɨɝɥɨɳɚɸɳɢɯ ɩɚɧɟɥɟɣ (ɩɚɧɟɥɢ ɁɉɄ) ɫ ɢɫɤɭɫɫɬɜɟɧɧɨ ɧɚɧɟɫɟɧɧɵɦ ɞɟɮɟɤɬɨɦ ɬɢɩɚ ɫɤɜɨɡɧɨɝɨ ɩɪɨɛɨɹ, ɩɨɫɥɟ ɥɨɤɚɥɶɧɨɝɨ ɪɟɦɨɧɬɚ. Ɉɛɪɚɡɰɵ-ɩɚɧɟɥɢ ɢɡɝɨɬɨɜɥɟɧɵ ɢɡ ɫɟɪɢɣɧɵɯ ɦɚɬɟɪɢɚɥɨɜ ɩɨ ɫɟɪɢɣɧɨɣ ɬɟɯɧɨɥɨɝɢɢ ɢɡ ɩɪɟɩɪɟɝɚ ɫɬɟɤɥɨɬɟɤɫɬɨɥɢɬɚ.ɂɫɫɥɟɞɨɜɚɧɢɹ ɩɪɨɜɨɞɢɥɢɫɶ ɧɚ ɭɧɢɜɟɪɫɚɥɶɧɨɣ ɷɥɟɤɬɪɨɦɟɯɚɧɢɱɟɫɤɨɣ ɫɢɫɬɟɦɟ Instron 5982 ɢ ɫɟɪɜɨɝɢɞɪɚɜɥɢɱɟɫɤɨɣ Instron 8801. Ⱦɥɹ ɚɧɚɥɢɡɚ ɧɚɩɪɹɠɟɧɧɨ-ɞɟɮɨɪɦɢ-ɪɨɜɚɧɧɨɝɨ ɫɨɫɬɨɹɧɢɹ ɞɟɮɨɪɦɢɪɭɟɦɵɯ ɷɥɟɦɟɧɬɨɜ ɜ ɪɚɛɨɬɟ ɢɫɩɨɥɶɡɭɟɬɫɹ ɛɟɫɤɨɧɬɚɤɬ-ɧɚɹ ɬɪɟɯɦɟɪɧɚɹ ɰɢɮɪɨɜɚɹ ɨɩɬɢɱɟɫɤɚɹ ɫɢɫɬɟɦɚ Vic-3D, ɦɚɬɟɦɚɬɢɱɟɫɤɢɣ ɚɩɩɚɪɚɬ ɤɨ-ɬɨɪɨɣ ɨɫɧɨɜɚɧ ɧɚ ɦɟɬɨɞɟ ɤɨɪɪɟɥɹɰɢɢ ɰɢɮɪɨɜɵɯ ɢɡɨɛɪɚɠɟɧɢɣ (DIC). Ⱦɥɹ ɤɨɧɬɪɨɥɹ ɜɧɭɬɪɟɧɧɟɣ ɝɟɨɦɟɬɪɢɢ ɨɛɪɚɡɰɚ ɢ ɨɰɟɧɤɢ ɜɨɡɦɨɠɧɵɯ ɞɟɮɟɤɬɨɜ ɨɫɭɳɟɫɬɜɥɹɥɚɫɶ ɬɟɩ-ɥɨɜɚɹ ɞɟɮɟɤɬɨɫɤɨɩɢɹ ɫ ɩɨɦɨɳɶɸ ɢɧɮɪɚɤɪɚɫɧɨɣ ɬɟɩɥɨɜɢɡɢɨɧɧɨɣ ɫɢɫɬɟɦɵ FLIR SC7000. ɉɪɟɞɥɨɠɟɧɵ ɦɟɬɨɞɢɤɢ ɫɨɜɦɟɫɬɧɨɝɨ ɢɫɩɨɥɶɡɨɜɚɧɢɹ ɢɫɩɵɬɚɬɟɥɶɧɵɯ ɢ ɢɡɦɟ-ɪɢɬɟɥɶɧɵɯ ɫɢɫɬɟɦ ɩɪɢ ɩɪɨɜɟɞɟɧɢɢ ɫɬɚɬɢɱɟɫɤɢɯ ɢ ɰɢɤɥɢɱɟɫɤɢɯ ɢɫɩɵɬɚɧɢɣ.Ɇɟɯɚɧɢɱɟɫɤɢɟ ɢɫɩɵɬɚɧɢɹ ɞɥɹ ɫɪɚɜɧɟɧɢɹ ɩɪɨɜɟɞɟɧɵ ɧɚ ɨɛɪɚɡɰɚɯ ɩɚɧɟɥɟɣ ɁɉɄ ɩɪɢ ɫɬɚɬɢɱɟɫɤɨɦ ɪɚɫɬɹɠɟɧɢɢ ɢ ɩɪɢ ɫɬɚɬɢɱɟɫɤɨɦ ɪɚɫɬɹɠɟɧɢɢ ɫ ɩɪɟɞɜɚɪɢɬɟɥɶɧɵɦ ɰɢɤɥɢɱɟɫɤɢɦ ɧɚɝɪɭɠɟɧɢɟɦ ɫ ɪɟɝɢɫɬɪɚɰɢɟɣ ɩɨɥɟɣ ɞɟɮɨɪɦɚɰɢɣ ɢ ɬɟɪɦɨɝɪɚɦɦ. ɋ ɰɟɥɶɸ ɚɧɚɥɢɡɚ ɦɟɯɚɧɢɡɦɨɜ ɪɚɡɪɭɲɟɧɢɹ ɨɛɪɚɡɰɚ-ɩɚɧɟɥɢ ɜ ɪɚɛɨɬɟ ɩɪɟɞɫɬɚɜɥɟɧɵ ɞɢɚɝɪɚɦɦɵ, ɩɨɫɬɪɨɟɧɧɵɟ ɜ ɩɪɨɰɟɫɫɟ ɢɫɩɵɬɚɧɢɣ ɧɚ ɫɬɚɬɢɱɟɫɤɨɟ ɪɚɫɬɹɠɟɧɢɟ. ɉɨ ɩɨɥɭɱɟɧɧɵɦ ɷɤɫɩɟɪɢɦɟɧɬɚɥɶɧɵɦ ɞɚɧɧɵɦ ɫ ɜɢɞɟɨɫɢɫɬɟɦɵ ɢɫɫɥɟɞɨɜɚɧɚ ɷɜɨɥɸɰɢɹ ɧɟɨɞɧɨɪɨɞɧɵɯ ɩɨɥɟɣ ɩɪɨɞɨɥɶɧɵɯ ɢ ɩɨɩɟɪɟɱɧɵɯ ɞɟɮɨɪɦɚɰɢɣ ɧɚ ɩɨɜɟɪɯɧɨɫɬɢ ɨɛ-ɪɚɡɰɨɜ-ɩɚɧɟɥɟɣ ɫ ɡɚɥɟɱɟɧɧɵɦ ɞɟɮɟɤɬɨɦ ɩɪɢ ɫɬɚɬɢɱɟɫɤɨɦ ɧɚɝɪɭɠɟɧɢɢ, ɚ ɬɚɤɠɟ ɩɪɢ ɰɢɤɥɢɱɟɫɤɢɯ ɢɫɩɵɬɚɧɢɹɯ. ɋ ɩɨɦɨɳɶɸ ɢɧɮɪɚɤɪɚɫɧɨɣ ɬɟɩɥɨɜɢɡɢɨɧɧɨɣ ɫɢɫɬɟɦɵ ɪɟ-ɝɢɫɬɪɢɪɨɜɚɥɢɫɶ ɜɧɭɬɪɟɧɧɹɹ ɫɬɪɭɤɬɭɪɚ, ɩɪɨɰɟɫɫɵ ɪɚɡɜɢɬɢɹ ɞɟɮɟɤɬɨɜ, ɚ ɬɚɤɠɟ ɪɚɫ-ɩɪɟɞɟɥɟɧɢɟ ɬɟɦɩɟɪɚɬɭɪ ɧɚ ɩɨɜɟɪɯɧɨɫɬɢ ɢɫɩɵɬɵɜɚɟɦɨɝɨ ɨɛɪɚɡɰɚ. © ɉɇɂɉɍɄɥɸɱɟɜɵɟ ɫɥɨɜɚ: ɷɤɫɩɟɪɢɦɟɧɬɚɥɶɧɚɹ ɦɟɯɚɧɢɤɚ, ɤɨɦɩɨɡɢɰɢɨɧɧɵɟ ɦɚɬɟɪɢɚɥɵ, ɦɟɬɨɞɢɤɢ ɢɫɩɵɬɚɧɢɣ, ɦɟɬɨɞ ɤɨɪɪɟɥɹɰɢɢ ɰɢɮɪɨɜɵɯ ɢɡɨɛɪɚɠɟɧɢɣ, ɢɧɮɪɚɤɪɚɫɧɚɹ ɬɟɩɥɨɜɢɡɢɨɧɧɚɹ ɫɢɫɬɟɦɚ, ɨɰɟɧɤɚ ɪɚɛɨɬɨɫɩɨɫɨɛɧɨɫɬɢ, ɩɚɧɟɥɢ ɁɉɄ, ɥɨɤɚɥɶɧɵɣ ɪɟɦɨɧɬ ɜɨɥɨɤɧɢɫɬɵɯ ɤɨɦɩɨɡɢɬɨɜ, ɰɢɤɥɢɱɟɫɤɢɟ ɢɫɩɵɬɚɧɢɹ, ɢɫɩɵɬɚɧɢɹ ɧɚ ɪɚɫɬɹɠɟɧɢɟ © Ʌɨɛɚɧɨɜ Ⱦɦɢɬɪɢɣ ɋɟɪɝɟɟɜɢɱ -ɦɥɚɞɲɢɣ ɧɚɭɱɧɵɣ ɫɨɬɪɭɞɧɢɤ, e-mail: cem.lobanov@gmail.com ȼɢɥɶɞɟɦɚɧ ȼɚɥɟɪɢɣ ɗɪɜɢɧɨɜɢɱ -ɞɨɤ...