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Showing 1 to 20 of 41 for “"Low velocity impact"”.
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Simulation of low-velocity impact damage in sandwich composites
… of composites is their high susceptibility to impact-induced damage, which may result in significant strength reduction or even structural collapse. A detailed understanding of the extent and nature of impact damage is thus greatly needed for damage tolerance based structural design and a …
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Low-Velocity Impact to High-Temperature Low-Sag Overhead Conductors
<p>High-Temperature Low-Sag (HTLS) conductors, such as Aluminum Conductor Composite Core (ACCC), improve infrastructure to support the delivery of power to meet the nation's increasing demand for electricity. Their response to low-velocity impacts during transportation, installation or in service, …
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Low-velocity Impact Analysis of Composite Repair Patches of Different Shapes
… repaired by the use of composite materials. Low velocity impact can cause barely visible damage to the interior structure of laminated composite. These impacts can cause delamination in composite materials. In this study, a Finite Element Analysis was conducted using Abaqus/Explicit and the …
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Computational Design of Transparent Polymeric Laminates subjected to Low-velocity Impact
… understanding of their deformations under impact loading and of energy dissipation mechanisms is needed for minimizing their weight. This requires verified and robust computational algorithms and validated mathematical models of the problem. Here we have developed a mathematical model for …
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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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Finite element analysis of permanent indentation of solids due to low velocity impact
… is developed. This model is subjected to an impact loading that produces plastic stresses. The finite element software COSMOS/M 1.7 is used to study the nonlinear behavior of the canister overpack. A new mechanism for energy absorption is adopted to determine the permanent indentation. The …
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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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Dynamic response of glass under low-velocity impact and high strain-rate compression loading
… characterized using a Dynatup 8250 drop weight impact test system, and a modified Split Hopkinson Pressure Bar (SHPB). In the low-velocity punch-shear experiment, similar trend has been observed for all glass types, and Starphire and Borosilicate demonstrated the highest total energy absorption. …
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Low velocity impact response of rc beam with artificial polyethylene aggregate as concrete block infill
… Based on the experimental results, the impact force, displacement and crack patterns were affected by the impact load. For RCAI specimens, the impact force was larger but smaller displacement value was observed, compared to the NRC specimens. Furthermore, the width of the cracks …
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Some issues concerning the dynamic response and damage of composite laminates subjected to low velocity impact
… on 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 …
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Improving Damage Tolerance of Composite Sandwich Structures Subjected to Low Velocity Impact Loading: Experimental and Numerical Analysis
… conventional composite facing skins exhibit low impact resistance in the transverse direction. Here, composite skin sandwich structures with three different impact resistant core materials were fabricated and tested both experimentally and numerically. Neat CFRP and 2024-T3 aluminum alloy …
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Low velocity impact response of laminated textile coir-aramids/epoxy hybrid composites subjected to transverse penetration loading
… fibre has been found to have a high potential as impact resistance, in which brittle fibre helps to spread the impact energy over a wider area. The focus of the study is to determine if any improvement in impact response exists as a result of combining high performance Kevlar synthetic fibre and …
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Shape Optimization of a Sandwich Composite Plate with Low-Velocity Impact Loading and Effect of Finite Difference Sensitivity Analysis
… the critical load cases in spacesuit design is a low-velocity impact (LVI) which may occur due to tool drop and other similar scenarios. The objectives of this work were (a) to create a finite element (FE) model of a component of a spacesuit, (b) validation of the FE model through experiments, (c) …
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Analytical behaviour of FRP strengthened reinforced concrete beams under low velocity impact load incorporating rate dependant material constitutive models
… of FRP strengthened RC beams subjected to low velocity impact events. Furthermore, many of the Finite Element (FE) analysis models developed in these studies yielded results that were inconsistent with the test data. Key shortcomings of these models relate to a lack of definition of the …
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The Effect of a Low-Velocity Impact on the Flexural Strength and Dynamic Response of Composite Sandwiches with Damage Arrestment Devices
<p>Impact strength is one of the most important structural properties for a designer to consider, but is often the most difficult to quantify or measure. A constant concern in the field of composites is the effect of foreign object impact damage because it is often undetectable by visual …
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Finite Element Modeling of Delamination Damage in Carbon Fiber Laminates Subject to Low-Velocity Impact and Comparison with Experimental Impact Tests Using Nondestructive Vibrothermography Evaluation
… in many design applications where high strength, low weight, and/or high stiffness are required. While composite materials can provide high strength and stiffness-to-weight ratios, they are also more complicated to analyze due to their inhomogeneous nature. One important failure mode of composite …
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Impact Damage Resistance of Shape Memory Alloy Hybrid Composite Structures
… hybrid composite plates, which can be used for low velocity impact or quasi-static contact loading, are derived. The governing equations include the transverse shear deformation to the first-order, large deformation of the plates, and SMA/epoxy lamina. The equations are derived in the general …
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Fluid-structure interaction of metallic and composite plates subjected to dynamic loading
… composite materials is theirsusceptibility to impact damage. Even under relatively low velocity impact, compositesare vulnerable to internal damage caused by transverse loads, but unlike metallicstructures, material damage can be hidden within the material and show no form ofexternal damage. In …
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Analysis of After Impact Characteristics and Structural Optimization of CFRP Composite Plate
<p>Low-velocity impact (LVI) on composites may cause Barely Visible Impact Damage (BVID), which is one of the most common damage types and may result in a decrease in strength of the composite. The objectives of this research were (a) to identify the characteristics of a carbon/epoxy composite …
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Time- and Temperature-Dependence of Fracture Energies Attributed to Copper/Epoxy Bonds
… fracture energies of peel specimens during low-velocity impact. This test has been successfully used to determine the apparent critical strain energy release rate of copper/epoxy bonds for low-velocity impact conditions (1-10 m/s), for a case of near-interfacial failure. The falling wedge …
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