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Showing 1 to 15 of 15 for “"Compression After Impact"”.
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Compression After Impact Experiments and Analysis on Honeycomb Core Sandwich Panels with Thin Facesheets
A better understanding of the effect of impact damage on composite structures is necessary to give the engineer an ability to design safe, efficient structures. Current composite structures suffer severe strength reduction under compressive loading conditions, due to even light damage, such as from …
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Compression After Impact Load Prediction in Graphite/Epoxy Laminates Using Acoustic Emission and Artificial Neural Networks
… neural networks (ANNs) in predicting the compression after impact (CAI) load of graphite/epoxy laminates from acoustic emission (AE) nondestructive testing (NDT) data. Thirty-four 24-ply bidirectional woven cloth laminate coupons were constructed and impacted at various energy levels …
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Ultimate Compression After Impact Load Prediction in Graphite/Epoxy Coupons Using Neural Network and Multivariate Statistical Analyses
… predict the ultimate compressive load of impact damaged graphite/epoxy coupons using a Kohonen self-organizing map (SOM) neural network and multivariate statistical regression analysis (MSRA). An optimized use of these data treatment tools allowed the generation of a simple, physically …
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Neural Network Prediction of Ultimate Compression After Impact Loads in Graphite-Epoxy Coupons from Ultrasonic C-Scan Images
… could predict the ultimate compressive loads of impact damaged 24-ply graphite-epoxy coupons from ultrasonic C-scan images. The 24-ply graphite-epoxy coupons were manufactured with bidirectional preimpregnated tape and cut into 21 coupons, 4 inches by 6 inches each. The coupons were impacted at …
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Damage Control Measures in Composites: Focus on Damage Tolerance of Aerospace Structures
<p>Barely Visible Impact Damage (BVID) in composite materials presents a stealthy yet significant risk to structural integrity, particularly challenging due to its elusive nature. The approach adopted here diverges from traditional methodologies, focusing on the novel application of Digital Image …
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Impact and energy absorption of laminated and sandwich composites
… increasingly being used in naval applications. Impact damage of laminated and sandwich composites under low-velocity and high-velocity impact are investigated. Delamination damage is explored in detail since delamination is one of the major failure modes of many advanced composites structures. …
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The effects of process parameters on the properties of resin transfer molded composites
… the void calculations. Mechanical tests included compression strength, inplane and interlaminar shear strengths, and impact. Compression after impact tests were performed and compared to undamaged compression strengths. The compression, inplane shear, and interlaminar shear strengths of the epoxy …
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Residual Compressive Strength Prediction of Carbon/Epoxy Laminates Subjected to Low Velocity Impact Damage
<p>Low energy impact damage to a composite structure is difficult to detect and can have profound effects on compressive strengths. Low energy impact damage is sometimes termed as barely visible impact damage (BVID). Detecting BVID is only possible by implementing nondestructive testing (NDT) …
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Compression of thick laminated composite beams with initial impact-like damage
While the study of compression after impact of laminated composites has been under consideration for many years. the complexity of the damage initiated by low velocity impact has not lent itself to simple predictive models for compression strength. The damage modes due to non-penetrating. low …
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Application of fracture mechanics to predict the growth of single and multi-level delaminations and disbonds in composite structures
… composite structures subjected to barely visible impact damage (BVID). The advantages of fracture mechanics-based methodologies to predict interlaminar failure in composite structures were identified, from which the crack tip element (CTE) approach and the virtual crack closure technique (VCCT) …
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Effect Of Impact Damage On Compression-Compression Fatigue Behavior Of Sandwich Composites
… research work was to investigate the effect of impact damage on in-plane buckling and compression-compression fatigue behavior for a new sandwich structure made from E-glass/epoxy face sheets over end-grain balsa wood core. Low velocity impact tests were carried out using a drop-weight impact …
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Out of autoclave manufacturing of cfrps having multiscale reinforcement for improved interlaminar fracture toughness and multifunctional characteristics
… either from fatigue loadings or low-velocity impact which are caused by the extension of multiple matrix cracks. Therefore, composites are highly susceptible to impact damage due to brittle matrix behaviour and poor impact damage tolerance. In light of this issue, the introduction of carbon …
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Development of self-healing techniques for fiber reinforced composites
… either from fatigue loadings or low velocity impact events. Conventional repair techniques of composites have a lot of drawbacks; are expensive, require extensive human work and cannot repair defects deep inside the material. Self-healing polymers is an approach which has not yet been …
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Autonomic healing of low-velocity impact damage in woven fiber-reinforced composites
… but are particularly susceptible to transverse impacts. Impact can significantly reduce strength and the extent of damage can grow under cyclic loading conditions. Because this type of damage often occurs below the surface, hidden from inspection, it is especially critical in structural …
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Some issues concerning the dynamic response and damage of composite laminates subjected to low velocity impact
… a few specific topics regarding the low velocity impact behaviour of laminated composites. These topics were chosen because of their significance as well as the relatively limited attention received so far by the scientific community. The first issue considered is the comparison between the …