The Experts below are selected from a list of 129 Experts worldwide ranked by ideXlab platform
R M Frizzell - One of the best experts on this subject based on the ideXlab platform.
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stress analysis of single bolt single lap Countersunk composite joints with variable bolt Hole clearance
Composite Structures, 2012Co-Authors: Brian Egan, C T Mccarthy, M A Mccarthy, R M FrizzellAbstract:Abstract Single-lap, carbon–epoxy joints with Countersunk fasteners were modelled using the nonlinear finite element code Abaqus. A highly-detailed analysis of the stress distribution at the Countersunk Hole boundary is provided. Bolt-Hole clearance, which arises due to limitations in manufacturing capabilities, is modelled extensively. Clearance levels both inside and outside typical aerospace fitting tolerances are studied and the finite element model is validated with experimental data. Plots of radial stress in each ply of the Countersunk laminate show the load transfer to be severely localised, with only a few plies bearing the majority of the load. The inclusion of clearance in the model was shown to result in far higher radial stresses compared to those in the neat-fit joint model. An associated loss in joint stiffness of more than 10% was recorded for the highest clearance considered (240 μm). Finally compressive through-thickness stresses are shown to be present at the damageable region of the Countersunk Hole, and increase with bolt-Hole clearance. These compressive stresses, which are an indicator of lateral constraint, are seen to suppress “brooming” failure in the Countersunk laminate.
Brian Egan - One of the best experts on this subject based on the ideXlab platform.
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Static and high-rate loading of single and multi-bolt carbon-epoxy aircraft fuselage joints
Composites Part A-applied Science and Manufacturing, 2013Co-Authors: Brian Egan, Conor T. Mccarthy, Michael A. Mccarthy, P.j. Gray, Ronan M. O'higginsAbstract:Abstract Single-lap shear behaviour of carbon–epoxy composite bolted aircraft fuselage joints at quasi-static and dynamic (5 m/s and 10 m/s) loading speeds is studied experimentally. Single and multi-bolt joints with Countersunk fasteners were tested. The initial joint failure mode was bearing, while final failure was either due to fastener pull-through or fastener fracture at a thread. Much less Hole bearing damage, and hence energy absorption, occurred when the fastener(s) fractured at a thread, which occurred most frequently in thick joints and in quasi-static tests. Fastener failure thus requires special consideration in designing crashworthy fastened composite structures; if it can be delayed, energy absorption is greater. A correlation between energy absorption in multi-bolt and single-bolt joint tests indicates potential to downsize future test programmes. Tapering a thin fuselage panel layup to a thicker layup at the Countersunk Hole proved highly effective in achieving satisfactory joint strength and energy absorption.
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stress analysis of single bolt single lap Countersunk composite joints with variable bolt Hole clearance
Composite Structures, 2012Co-Authors: Brian Egan, C T Mccarthy, M A Mccarthy, R M FrizzellAbstract:Abstract Single-lap, carbon–epoxy joints with Countersunk fasteners were modelled using the nonlinear finite element code Abaqus. A highly-detailed analysis of the stress distribution at the Countersunk Hole boundary is provided. Bolt-Hole clearance, which arises due to limitations in manufacturing capabilities, is modelled extensively. Clearance levels both inside and outside typical aerospace fitting tolerances are studied and the finite element model is validated with experimental data. Plots of radial stress in each ply of the Countersunk laminate show the load transfer to be severely localised, with only a few plies bearing the majority of the load. The inclusion of clearance in the model was shown to result in far higher radial stresses compared to those in the neat-fit joint model. An associated loss in joint stiffness of more than 10% was recorded for the highest clearance considered (240 μm). Finally compressive through-thickness stresses are shown to be present at the damageable region of the Countersunk Hole, and increase with bolt-Hole clearance. These compressive stresses, which are an indicator of lateral constraint, are seen to suppress “brooming” failure in the Countersunk laminate.
Hua Wang - One of the best experts on this subject based on the ideXlab platform.
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effects of Countersunk Hole s geometrical deviation on the strength of bolted carbon fiber reinforced plastic polymer metal joints under tensile loading
Proceedings of the Institution of Mechanical Engineers Part B: Journal of Engineering Manufacture, 2020Co-Authors: Bo Liu, Chen Yan, Hua WangAbstract:Countersinking process introduces variations in the angle and depth of the Countersunk Hole due to the wearing down of the drilling bit and the specific properties of carbon fiber–reinforced plasti...
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Effects of Countersunk Hole’s geometrical deviation on the strength of bolted carbon fiber–reinforced plastic/polymer metal joints under tensile loading:
Proceedings of the Institution of Mechanical Engineers Part B: Journal of Engineering Manufacture, 2019Co-Authors: Hua WangAbstract:Countersinking process introduces variations in the angle and depth of the Countersunk Hole due to the wearing down of the drilling bit and the specific properties of carbon fiber–reinforced plasti...
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Tolerance Allocation With Simulation-Based Digital Twin for CFRP-Metal Countersunk Bolt Joint
Volume 2: Advanced Manufacturing, 2018Co-Authors: Hua Wang, Mengqian Zhou, Bo LiuAbstract:Deviations in the Countersunk Hole’s angle and depth affect the strength of the bolted composites under tensile loading. Tolerance of the Countersunk Hole’s angle and depth could be allocated by the Digital Twin of the bolted CFRP-Metal bolt joint. The paper presents a simulation-based Digital Twin for tolerance allocation of CFRP-Metal Countersunk bolt joint, mainly considering the strength of the single bolt Countersunk joint. Using the design-of-experiment method, nine numerical models with different Hole’s angle and depth are constructed to simulate the Countersunk Holes with different deviations. Simulation results are input into the Digital Twin of the CFRP-Metal Countersunk bolt joint. Analysis of variation (ANOVA) method is employed to deeply investigate the interaction between the angle deviation and the depth deviation under tensile loading. Tolerance of the Countersunk Hole is allocated based on the proposed Digital Twin involving simulation information. The depth should be more strictly controlled than the angle during the course of countersinking. The reported work enhances the understanding of the tolerance allocation for the bolted joint of the composites, and of the simulation-based Digital Twin for CFRP-Metal Countersunk bolt joint.
Liang Wang - One of the best experts on this subject based on the ideXlab platform.
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Three-dimensional layer-by-layer stress analysis of single-lap, Countersunk composite joints with varying joining interface conditions
Composite Structures, 2018Co-Authors: Yunong Zhai, Liang WangAbstract:Abstract Due to manufacturing variations of composite parts, assembly gap and consequent shimming widely occur in the airframe skin-structure. To guarantee the safety and reliability, the aircraft manufacturers expect to fully understand the effect of assembly gap and shimming on the loading behavior of composite skin joints. One of the main concerns is the effect of interface gap and shimming on the elastic stress state at the Hole due to skin joints involve significant stress concentration and composite parts present brittleness and limited stress relief ability. But this topic has not yet been reported so far. In this paper, the effect of joining interface condition (including both shimming and interface gap) on three-dimensional layer-by-layer stress field at the Countersunk Hole of single-lap Countersunk composite joints was fully and systematically investigated by employing a three-dimensional FE model. Shimming conditions include material type and shim thickness, and interface gap conditions include gap span and gap thickness. Some previously unrevealed conclusions were concluded. This study could contribute to improving the reliability of composite airframe, and benefit both design and manufacture in aircraft industry.
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an experimental study on the effect of joining interface condition on bearing response of single lap Countersunk composite aluminum bolted joints
Composite Structures, 2015Co-Authors: Yunong Zhai, Dongsheng Li, Xiaoqiang Li, Liang WangAbstract:Abstract An experimental study on the effect of joining interface condition (including shimming and interface gap) on bearing response of single-lap, Countersunk composite-aluminum bolted joints are presented. The specimens consisted of a T700/3068 carbon/epoxy laminate with quasi-isotropic lay-up and an Aluminum alloy 7075T651 substrate. Bearing stress/bearing strain behavior were obtained according to ASTM standard. Both solid shim and liquid shim were considered and a comparison was made for them. 3D Digital Image Correlation was utilized to evaluate the effect of shimming on the surface strain distribution and out-of-plane deformation of the joints. One focus of the study was to investigate the effect of interface gap on the bearing performance of composite bolted joints. The interface gap was designed and characterized by variable parameters, i.e., thickness and span. It is found that compared to liquid-shim series, specimens with solid shim gain a little better bearing performance because of higher joint bending stiffness that benefits from the higher tensile modulus of solid peelable fiberglass shim. The presence of interface gap significantly weakens the bearing performance of single-lap, Countersunk composite-aluminum joints by making the Countersunk Hole losing support from aluminum plate at the shear plane, and meanwhile intensifying the loading eccentricity of single-lap joints.
C T Mccarthy - One of the best experts on this subject based on the ideXlab platform.
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stress analysis of single bolt single lap Countersunk composite joints with variable bolt Hole clearance
Composite Structures, 2012Co-Authors: Brian Egan, C T Mccarthy, M A Mccarthy, R M FrizzellAbstract:Abstract Single-lap, carbon–epoxy joints with Countersunk fasteners were modelled using the nonlinear finite element code Abaqus. A highly-detailed analysis of the stress distribution at the Countersunk Hole boundary is provided. Bolt-Hole clearance, which arises due to limitations in manufacturing capabilities, is modelled extensively. Clearance levels both inside and outside typical aerospace fitting tolerances are studied and the finite element model is validated with experimental data. Plots of radial stress in each ply of the Countersunk laminate show the load transfer to be severely localised, with only a few plies bearing the majority of the load. The inclusion of clearance in the model was shown to result in far higher radial stresses compared to those in the neat-fit joint model. An associated loss in joint stiffness of more than 10% was recorded for the highest clearance considered (240 μm). Finally compressive through-thickness stresses are shown to be present at the damageable region of the Countersunk Hole, and increase with bolt-Hole clearance. These compressive stresses, which are an indicator of lateral constraint, are seen to suppress “brooming” failure in the Countersunk laminate.
