Evaluation of the failure progress in the static bending of GFRP laminates reinforced with a classic plain‐woven fabric and a 3D fabric, by means of the vibrations analysis

Abstract

The aim of the work is to evaluate the effectiveness of analysis of a failure progress of the glass fiber reinforced polymer laminate (classic and 3D), during static bending, with the use of high frequency vibration analysis (the order of kHz). During the tests, the instantaneous velocity of the samples' vibrations was recorded. The 3D laminate showed a more favorable course of failure (mostly fiber fracture) than the classic laminate (mostly delamination), but only in the direction transverse to the translaminar interweave strands. In the direction parallel to the interweave, it was also characterized mainly by delamination. It was stated that the vibration measurements significantly broaden and supplement the characteristics of bending, by way of revealing the local degradation changes in the examined material, especially before the initiation of the main stage of failure. The work also describes the frequency bands in which the symptoms of the occurring failures of particular laminate components were observed and where the values of the basic point parameters were estimated, which points to the occurrence of structure failure. The obtained results confirm the effectiveness of the vibration analysis as a tool for the evaluation of the course of composite material failure under static loads. POLYM. COMPOS., 38:1070–1085, 2017. © 2015 Society of Plastics Engineers

Prediction of transport vehicles’ durability with consideration of corrosive surface cracks propagation in structural elements

“…At initial and final terms: To realize the mathematical model (16)(17)(18), the following approximate approach [12][13] is proposed, according to which the change in the area of a moving crack of the considered configuration is approximately the same as for a semicircular crack of a radius a of a plane initial area. The rate of periphery propagation of such a crack is defined by the constant in all its points for the maximum value…”

“…When transporting fertilizers, poisonous chemicals and other aggressive agrarian products, the dust of these substances is deposited on the structure surface. The combination of dust and moisture creates an aggressive environment, which, together with the operating loads (usually cyclic), leads to intense corrosion damage, in particular, by propagating surface corrosionfatigue cracks in elements of vehicular structures [1][2][3][4][5][6][7][8][14][15][16][17][18][19][20][21][22]. The corrosion processes rate is known to be a function of the aggressiveness and duration of the environment effect, the air temperature, the metal surface state (composition and structure of the protective film), the chemical composition of the metal, the presence of mechanical stresses, structural features (welds, bolt and rivet joints), and the combination of elements creating cavities or cracks, in which moisture condenses.…”

Impact of Application of Selected Composite Materials on the Weight and Vibroactivity of the Upper Gearbox Housing

“…According to the information available in the scientific and industrial literature, composite materials have not yet been subjected to detailed vibroacoustic tests. Some works in this area have been published by the authors of this study, among others [54,55]. In the literature, there is a distinct lack of manufacturing and functional guidelines concerning the vibroacoustic properties of composite materials that can be used in the construction of means of transport and gearboxes.…”

Failure Progress of 3D Reinforced GFRP Laminate during Static Bending, Evaluated by Means of Acoustic Emission and Vibrations Analysis

“…The authors established there that the main cause of laminate failure during bending is delamination, which was clearly proven in acoustic emission tests [55], as well as vibration analysis [53,54]. As a continuation of the studies, the authors propose a new idea of analyzing the 3D woven laminate failure progress.…”

“…The method had its value already confirmed in the assessment of laminate failure progress, among others, in [53,54]. To analyze the vibration signal efficiently, the proper signal measure must be used [57,58].…”