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Composite materials usage in several industrial fields is now widespread, and this leads to the necessity of overcoming issues that are still currently open. In the aeronautic industry, this is especially true for Barely Visible Impact Damage (BVID) and humidity uptake issues. BVID is the most insidious kind of impact damage, being rather common and not easily detectable. These, along with the ageing that a composite structure could face during its operative life, could be a cause of fatal failures. In this paper, the influence of water absorption on impacted specimens compressive residual strength was studied. Specimens were impacted using a modified Charpy pendulum. Two different locations were chosen for comparison: Near-Edge (NE) and Central (CI). Accelerated hygrothermal ageing was conducted on impacted and reference nonimpacted coupons, placing them in a water-filled jar at 70 °C. Compressive tests were performed in accordance with the Combined Loading Compression (CLC) test method. A Dynamic Mechanical Analysis (DMA) was performed as well. The results showed the influence of hygrothermal ageing, as expected. Nevertheless, the influence of impact location on compressive residual strength is not clearly noticeable in aged specimens, leading to the conclusion that hygrothermal ageing may have a greater effect on composite compressive strength than the analysed BVI damage.
Maria Falaschetti; Matteo Scafé; Nicola Zavatta; Enrico Troiani. Hygrothermal Ageing Influence on BVI-Damaged Carbon/Epoxy Coupons under Compression Load. Polymers 2021, 13, 2038 .
AMA StyleMaria Falaschetti, Matteo Scafé, Nicola Zavatta, Enrico Troiani. Hygrothermal Ageing Influence on BVI-Damaged Carbon/Epoxy Coupons under Compression Load. Polymers. 2021; 13 (13):2038.
Chicago/Turabian StyleMaria Falaschetti; Matteo Scafé; Nicola Zavatta; Enrico Troiani. 2021. "Hygrothermal Ageing Influence on BVI-Damaged Carbon/Epoxy Coupons under Compression Load." Polymers 13, no. 13: 2038.
Wing shape adaptability during flight is the next step towards the greening of aviation. The shape of the wing is typically designed for one cruise point or a weighted average of several cruise points. However, a wing is subjected to a variety of flight conditions, which results in the aircraft flying sub-optimally during a portion of the flight. Shape adaptability can be achieved by tuning the shape of the winglet during flight. The design challenge is to combine a winglet structure that is able to allow the required adaptable shape while preserving the structural integrity to carry the aerodynamic loads. The shape changing actuators must work against the structural strains and the aerodynamic loads. Analyzing the full model in the preliminary design phase is computationally expensive; therefore, it is necessary to develop a model. The goal of this paper is to derive an aeroelastic model for a wing and winglet in order to reduce the computational cost and complexity of the system in designing a folding winglet. In this paper, the static aeroelastic analysis is performed for a regional aircraft wing at sea level and service ceiling conditions with three degree and eight degree angle of attack. MSC Nastran Aeroelastic tool is used to develop a Finite Element Model (FEM), i.e., beam model and the aerodynamic loads are calculated based on a doublet lattice panel method (DLM).
Bereket Sitotaw Kidane; Enrico Troiani. Static Aeroelastic Beam Model Development for Folding Winglet Design. Aerospace 2020, 7, 106 .
AMA StyleBereket Sitotaw Kidane, Enrico Troiani. Static Aeroelastic Beam Model Development for Folding Winglet Design. Aerospace. 2020; 7 (8):106.
Chicago/Turabian StyleBereket Sitotaw Kidane; Enrico Troiani. 2020. "Static Aeroelastic Beam Model Development for Folding Winglet Design." Aerospace 7, no. 8: 106.
Resin transfer molding (RTM) technologies are widely used in automotive, marine, and aerospace applications. The need to evaluate the impact of design and production critical choices, also in terms of final costs, leads to the wider use of numerical simulation in the preliminary phase of component development. The main issue for accurate RTM analysis is the reliable characterization of the involved materials. The aim of this paper is to present a validated methodology for material characterization to be implemented and introduce data elaboration in the ESI PAM-RTM software. Experimental campaigns for reinforcement permeabilities and resin viscosity measurement are presented and discussed. Finally, the obtained data are implemented in the software and then compared to experimental results in order to validate the described methodology.
Maria Pia Falaschetti; Francesco Rondina; Nicola Zavatta; Lisa Gragnani; Martina Gironi; Enrico Troiani; Lorenzo Donati. Material Characterization for Reliable Resin Transfer Molding Process Simulation. Applied Sciences 2020, 10, 1814 .
AMA StyleMaria Pia Falaschetti, Francesco Rondina, Nicola Zavatta, Lisa Gragnani, Martina Gironi, Enrico Troiani, Lorenzo Donati. Material Characterization for Reliable Resin Transfer Molding Process Simulation. Applied Sciences. 2020; 10 (5):1814.
Chicago/Turabian StyleMaria Pia Falaschetti; Francesco Rondina; Nicola Zavatta; Lisa Gragnani; Martina Gironi; Enrico Troiani; Lorenzo Donati. 2020. "Material Characterization for Reliable Resin Transfer Molding Process Simulation." Applied Sciences 10, no. 5: 1814.
Laser shock peening has established itself as an effective surface treatment to enhance the fatigue properties of metallic materials. Although a number of works have dealt with the formation of residual stresses, and their consequent effects on the fatigue behavior, the influence of material geometry on the peening process has not been widely addressed. In this paper, Laser Peening without Coating (LPwC) is applied at the surface of a notch in specimens made of a 6082-T6 aluminum alloy. The treated specimens are tested by three-point bending fatigue tests, and their fatigue life is compared to that of untreated samples with an identical geometry. The fatigue life of the treated specimens is found to be 1.7 to 3.3 times longer. Brinell hardness measurements evidence an increase in the surface hardness of about 50%, following the treatment. The material response to peening is modelled by a finite element model, and the compressive residual stresses are computed accordingly. Stresses as high as −210 MPa are present at the notch. The ratio between the notch curvature and the laser spot radius is proposed as a parameter to evaluate the influence of the notch.
Enrico Troiani; Nicola Zavatta. The Effect of Laser Peening without Coating on the Fatigue of a 6082-T6 Aluminum Alloy with a Curved Notch. Metals 2019, 9, 728 .
AMA StyleEnrico Troiani, Nicola Zavatta. The Effect of Laser Peening without Coating on the Fatigue of a 6082-T6 Aluminum Alloy with a Curved Notch. Metals. 2019; 9 (7):728.
Chicago/Turabian StyleEnrico Troiani; Nicola Zavatta. 2019. "The Effect of Laser Peening without Coating on the Fatigue of a 6082-T6 Aluminum Alloy with a Curved Notch." Metals 9, no. 7: 728.
This study focuses on the development of a source identification algorithm inspired by the SHAZAM music app. The algorithm makes use of a spectrogram analysis technique for distinguishing different Acoustic Emission (AE) events. The peaks of the spectrogram are used to obtain a constellation map generating a “fingerprint” like pattern for each acoustic emission source. The fingerprints are then used within an artificial intelligence algorithm as part of a Knowledge Discovery database. The database is then able to link the AE signal to a specific source type. An experimental program was developed to test the methodology. The results of this study demonstrate that signal sources can be classified and linked to specific emission types with a high level of accuracy
Niccolo Facciotto; Marcias Martinez; Enrico Troiani. Source Identification and Classification of Acoustic Emission Signals by a SHAZAM-inspired Pattern Recognition Algorithm. Structural Health Monitoring 2017 2017, 1 .
AMA StyleNiccolo Facciotto, Marcias Martinez, Enrico Troiani. Source Identification and Classification of Acoustic Emission Signals by a SHAZAM-inspired Pattern Recognition Algorithm. Structural Health Monitoring 2017. 2017; (shm):1.
Chicago/Turabian StyleNiccolo Facciotto; Marcias Martinez; Enrico Troiani. 2017. "Source Identification and Classification of Acoustic Emission Signals by a SHAZAM-inspired Pattern Recognition Algorithm." Structural Health Monitoring 2017 , no. shm: 1.
The issue of cross-ply testing to determine mechanical properties for the characterization of the strength of composite laminates is fundamental to fiber–polymer composites, because experience has shown that this technique leads to more accurate and more representative characterizations for the tensile and compressive strengths of unidirectional composite laminae than those achieved by direct measurement. The indirect analytical method for the evaluation of the tensile and compressive strength of UD laminates at 0° is based on the application of the so-called Back-Out Factor (BF), a multiply factor determined by using the experimental values obtained from tensile and compressive tests on cross-ply specimens.
L.J. Hart-Smith; E. Troiani. 7.7 Backing-Out Composite Lamina Strengths from Cross-Ply Testing. Comprehensive Composite Materials II 2017, 119 -130.
AMA StyleL.J. Hart-Smith, E. Troiani. 7.7 Backing-Out Composite Lamina Strengths from Cross-Ply Testing. Comprehensive Composite Materials II. 2017; ():119-130.
Chicago/Turabian StyleL.J. Hart-Smith; E. Troiani. 2017. "7.7 Backing-Out Composite Lamina Strengths from Cross-Ply Testing." Comprehensive Composite Materials II , no. : 119-130.
M.P. Falaschetti; M. Scafè; A. Tatì; E. Troiani. Experimental determination of thickness influence on compressive residual strength of impacted carbon/epoxy laminate. Procedia Structural Integrity 2017, 3, 237 -245.
AMA StyleM.P. Falaschetti, M. Scafè, A. Tatì, E. Troiani. Experimental determination of thickness influence on compressive residual strength of impacted carbon/epoxy laminate. Procedia Structural Integrity. 2017; 3 ():237-245.
Chicago/Turabian StyleM.P. Falaschetti; M. Scafè; A. Tatì; E. Troiani. 2017. "Experimental determination of thickness influence on compressive residual strength of impacted carbon/epoxy laminate." Procedia Structural Integrity 3, no. : 237-245.
Enrico Troiani. Analytical evaluation of the Stress Intensity Factor in stiffened sheets with multiple side damage. AIMS Materials Science 2016, 3, 1615 -1622.
AMA StyleEnrico Troiani. Analytical evaluation of the Stress Intensity Factor in stiffened sheets with multiple side damage. AIMS Materials Science. 2016; 3 (4):1615-1622.
Chicago/Turabian StyleEnrico Troiani. 2016. "Analytical evaluation of the Stress Intensity Factor in stiffened sheets with multiple side damage." AIMS Materials Science 3, no. 4: 1615-1622.
Enrico Troiani; Maria Pia Falaschetti; Sara Taddia; Alessandro Ceruti. CFRP Crash Absorbers in Small UAV: Design and Optimization. SAE Technical Paper Series 2015, 1, 1 .
AMA StyleEnrico Troiani, Maria Pia Falaschetti, Sara Taddia, Alessandro Ceruti. CFRP Crash Absorbers in Small UAV: Design and Optimization. SAE Technical Paper Series. 2015; 1 ():1.
Chicago/Turabian StyleEnrico Troiani; Maria Pia Falaschetti; Sara Taddia; Alessandro Ceruti. 2015. "CFRP Crash Absorbers in Small UAV: Design and Optimization." SAE Technical Paper Series 1, no. : 1.
In order to evaluate the effectiveness of the Laser Shock Peening (LSP) in reducing the fatigue related problems in metallic structures, thin aluminum specimens have been peened along straight patterns perpendicular to the crack. Despite of the induced compressive residual stresses, the tests showed a negative effect of the LSP on the fatigue crack propagation performances. Starting from the numerical assessment of the self-balancing residual stress distribution and the measurements of the residual stresses, the fatigue crack growth has been analytically evaluated and compared with experimental results. The comparison highlights the sensitivity of the crack propagation to the width of the LSP treated strip and its position relative to the crack.
Sara Taddia; Enrico Troiani. Effect of Laser Shock Peening on the Fatigue Behavior of Thin Aluminum Panels. Materials Today: Proceedings 2015, 2, 5006 -5014.
AMA StyleSara Taddia, Enrico Troiani. Effect of Laser Shock Peening on the Fatigue Behavior of Thin Aluminum Panels. Materials Today: Proceedings. 2015; 2 (10):5006-5014.
Chicago/Turabian StyleSara Taddia; Enrico Troiani. 2015. "Effect of Laser Shock Peening on the Fatigue Behavior of Thin Aluminum Panels." Materials Today: Proceedings 2, no. 10: 5006-5014.
M.P. Falaschetti; M. Scafè; Enrico Troiani; V. Agostinelli; S. Sangiorgi. Experimental Determination of Compressive Residual Strength of a Carbon/epoxy Laminate after a Near-edge Impact. Procedia Engineering 2015, 109, 171 -180.
AMA StyleM.P. Falaschetti, M. Scafè, Enrico Troiani, V. Agostinelli, S. Sangiorgi. Experimental Determination of Compressive Residual Strength of a Carbon/epoxy Laminate after a Near-edge Impact. Procedia Engineering. 2015; 109 ():171-180.
Chicago/Turabian StyleM.P. Falaschetti; M. Scafè; Enrico Troiani; V. Agostinelli; S. Sangiorgi. 2015. "Experimental Determination of Compressive Residual Strength of a Carbon/epoxy Laminate after a Near-edge Impact." Procedia Engineering 109, no. : 171-180.
In the paper the Friction Welding (FRW) process is investigated by means of FEM simulation and experimental trials on AA 6082-T6 round extruded bars. Tests are realized at different rotational speeds and forging forces: the thermal field is monitored by means of k-type contact thermocouples and a contactless self-calibrating pyrometer. Deform lagrangian code is initially validated and optimized for process simulation of experimental trials then the simulations were used for the analysis of welding quality (through welding criteria) and for the microstructure evolution by means of a model already developed by the authors for aluminum extrusion microstructure evolution prediction.
Lorenzo Donati; Enrico Troiani; Paolo Proli; Luca Tomesani. FEM Analysis and Experimental Validation of Friction Welding Process of 6xxx Alloys for the Prediction of Welding Quality. Materials Today: Proceedings 2015, 2, 5045 -5054.
AMA StyleLorenzo Donati, Enrico Troiani, Paolo Proli, Luca Tomesani. FEM Analysis and Experimental Validation of Friction Welding Process of 6xxx Alloys for the Prediction of Welding Quality. Materials Today: Proceedings. 2015; 2 (10):5045-5054.
Chicago/Turabian StyleLorenzo Donati; Enrico Troiani; Paolo Proli; Luca Tomesani. 2015. "FEM Analysis and Experimental Validation of Friction Welding Process of 6xxx Alloys for the Prediction of Welding Quality." Materials Today: Proceedings 2, no. 10: 5045-5054.
In this paper a new method for nondestructive testing (NDT), applied to carbon fiber composite materials, is investigated. The approach is based on the comparison between the electromagnetic signal reflected by the carbon fiber composite sheet under test, when an ultra-wideband (UWB) signal is incident on it, and the one reflected by a healthy sheet. The possible presence of a defect is then revealed by an appropriate metric measuring the mismatch between the two reflected waveforms. The performance of different metrics is investigated, for two defect types, based on real measurements in an indoor environment. As an outcome of our experimental activity, very promising results have been obtained for one of the tested metrics, which allows to accurately detect surface defects with a size comparable to the radar resolution on a carbon fiber composite sheet.
Simone Gubinelli; Enrico Paolini; Andrea Giorgetti; Matteo Mazzotti; Andrea Rizzo; Enrico Troiani; Marco Chiani. An ultra-wideband radar approach to nondestructive testing. 2014 IEEE International Conference on Ultra-WideBand (ICUWB) 2014, 303 -308.
AMA StyleSimone Gubinelli, Enrico Paolini, Andrea Giorgetti, Matteo Mazzotti, Andrea Rizzo, Enrico Troiani, Marco Chiani. An ultra-wideband radar approach to nondestructive testing. 2014 IEEE International Conference on Ultra-WideBand (ICUWB). 2014; ():303-308.
Chicago/Turabian StyleSimone Gubinelli; Enrico Paolini; Andrea Giorgetti; Matteo Mazzotti; Andrea Rizzo; Enrico Troiani; Marco Chiani. 2014. "An ultra-wideband radar approach to nondestructive testing." 2014 IEEE International Conference on Ultra-WideBand (ICUWB) , no. : 303-308.
Raffaella Di Sante; Lorenzo Donati; Enrico Troiani; Paolo Proli. Evaluation of bending strain measurements in a composite sailboat bowsprit with embedded fibre Bragg gratings. Measurement 2014, 54, 106 -117.
AMA StyleRaffaella Di Sante, Lorenzo Donati, Enrico Troiani, Paolo Proli. Evaluation of bending strain measurements in a composite sailboat bowsprit with embedded fibre Bragg gratings. Measurement. 2014; 54 ():106-117.
Chicago/Turabian StyleRaffaella Di Sante; Lorenzo Donati; Enrico Troiani; Paolo Proli. 2014. "Evaluation of bending strain measurements in a composite sailboat bowsprit with embedded fibre Bragg gratings." Measurement 54, no. : 106-117.
Flat thin aluminum panels with centered crack have been Laser Shock Penned along straight patterns perpendicular to the crack. Despite of the locally induced compressive residual stresses, the experimental tests showed the negative effect of the LSP on the fatigue crack propagation performances of panels. Starting from the numerical assessment of the self-balancing residual stress distribution along the entire panel width, the fatigue crack growth through the panels has been analytically evaluated and compared with experimental results, showing a good agreement. The comparison highlights the sensitivity of the fatigue crack propagation life to the selected LSP pattern configuration (i.e. the width of the LSP treated strip and the relative position to the crack centre) which have to be accurately setup in order to exploit the full potentiality of the LSP process in increasing the fatigue life and avoid undesired reduction of the component performances.
Enrico Troiani; Sara Taddia; Ivan Meneghin; Gianluca Molinari. Fatigue Crack Growth in Laser Shock Peened Thin Metallic Panels. Advanced Materials Research 2014, 996, 775 -781.
AMA StyleEnrico Troiani, Sara Taddia, Ivan Meneghin, Gianluca Molinari. Fatigue Crack Growth in Laser Shock Peened Thin Metallic Panels. Advanced Materials Research. 2014; 996 ():775-781.
Chicago/Turabian StyleEnrico Troiani; Sara Taddia; Ivan Meneghin; Gianluca Molinari. 2014. "Fatigue Crack Growth in Laser Shock Peened Thin Metallic Panels." Advanced Materials Research 996, no. : 775-781.
In this work has been estimated the compressive strength of a unidirectional lamina of a\ud carbon/epoxy composite material, using the cross-ply and angle-ply laminates.\ud Over the years various methods have been developed to deduce compressive properties of composite materials\ud reinforced with long fibres. Each of these methods is characterized by a specific way of applying load to the\ud specimen.\ud The method chosen to perform the compression tests is the Wyoming Combined Loading Compression (CLC)\ud Test Method, described in ASTM D 6641 / D 6641M-09. This method presents many advantages, especially:\ud the load application on the specimen (end load combined with shear load), the reproducibility of measurements\ud and the experimental equipment quite simplified.\ud Six different laminates were tested in compressive tests. They were realized by the same unidirectional prepreg,\ud but with different stacking sequences: two cross-ply [0/90]ns, two angle-ply [0/90/±45]ns and two\ud unidirectional laminates [0]ns and [90]ns.\ud The estimate of the compressive strength of the unidirectional laminates at 0°, was done by an indirect\ud analytical method, developed from the classical lamination theory, and which uses a multiplicative parameter\ud known as Back-out Factor (BF). The BF is determined by using the experimental values obtained from\ud compression tests
M. Scafè; G. Raiteri; A. Brentari; R. Dlacic; Enrico Troiani; M. P. Falaschetti; E. Besseghini. Estimate of compressive strength of an unidirectional composite lamina using cross-ply and angle-ply laminates. Frattura ed Integrità Strutturale 2014, 8, 399 -409.
AMA StyleM. Scafè, G. Raiteri, A. Brentari, R. Dlacic, Enrico Troiani, M. P. Falaschetti, E. Besseghini. Estimate of compressive strength of an unidirectional composite lamina using cross-ply and angle-ply laminates. Frattura ed Integrità Strutturale. 2014; 8 (29):399-409.
Chicago/Turabian StyleM. Scafè; G. Raiteri; A. Brentari; R. Dlacic; Enrico Troiani; M. P. Falaschetti; E. Besseghini. 2014. "Estimate of compressive strength of an unidirectional composite lamina using cross-ply and angle-ply laminates." Frattura ed Integrità Strutturale 8, no. 29: 399-409.
Enrico Troiani; Lorenzo Donati; Gianluca Molinari; Raffaella Di Sante. Influence of Plying Strategies and Trigger Type on Crashworthiness Properties of Carbon Fiber Laminates Cured through Autoclave Processing. Strojniški vestnik – Journal of Mechanical Engineering 2014, 60, 375 -381.
AMA StyleEnrico Troiani, Lorenzo Donati, Gianluca Molinari, Raffaella Di Sante. Influence of Plying Strategies and Trigger Type on Crashworthiness Properties of Carbon Fiber Laminates Cured through Autoclave Processing. Strojniški vestnik – Journal of Mechanical Engineering. 2014; 60 (6):375-381.
Chicago/Turabian StyleEnrico Troiani; Lorenzo Donati; Gianluca Molinari; Raffaella Di Sante. 2014. "Influence of Plying Strategies and Trigger Type on Crashworthiness Properties of Carbon Fiber Laminates Cured through Autoclave Processing." Strojniški vestnik – Journal of Mechanical Engineering 60, no. 6: 375-381.
This work investigated issues for an efficient and reliable embedding and use of Fiber Bragg Grating (FBG) sensors for strain monitoring of composite structures with particular regard to the manufacturing process of components in the nautical field by means of the vacuum bag technique in autoclave. CFRP material laminates with embedded FBGs were produced and the effect of the curing process parameters on the light transmission characteristics of the optical fibers was initially investigated. Two different types of coating, namely polyimide and acrylate, were tested by measuring the light attenuation by an Optical Time Domain Reflectometer. Tensile specimens were subsequently extracted from the laminas and instrumented also with a surface-mounted conventional electrical strain gage (SG). Comparison between the FBG and SG measurements during static tensile tests allowed the evaluation of the strain monitoring capability of the FBGs, in particular of their sensitivity (i.e., gage factor) when embedded.
Raffaella Di Sante; Lorenzo Donati; Enrico Troiani; Paolo Proli. Reliability and accuracy of embedded fiber Bragg grating sensors for strain monitoring in advanced composite structures. Metals and Materials International 2014, 20, 537 -543.
AMA StyleRaffaella Di Sante, Lorenzo Donati, Enrico Troiani, Paolo Proli. Reliability and accuracy of embedded fiber Bragg grating sensors for strain monitoring in advanced composite structures. Metals and Materials International. 2014; 20 (3):537-543.
Chicago/Turabian StyleRaffaella Di Sante; Lorenzo Donati; Enrico Troiani; Paolo Proli. 2014. "Reliability and accuracy of embedded fiber Bragg grating sensors for strain monitoring in advanced composite structures." Metals and Materials International 20, no. 3: 537-543.
Laser Shock Peening (LSP) is a material enhancement process used to introduce compressive residual stresses in metallic components. This investigation explored the effects of different combinations of LSP parameters, such as irradiance (GW/cm2) and laser pulse density (spots/mm2), on 3.2 mm thick AA6056-T4 samples, for integral airframe applications. The most significant effects that are introduced by LSP without a protective coating include residual stress and surface roughness, since each laser pulse vaporizes the surface layer of the target. Each of these effects was quantified, whereby residual stress analysis was performed using X-ray diffraction with synchrotron radiation. A series of fully reversed bending fatigue tests was conducted, in order to evaluate fatigue performance enhancements with the aim of identifying LSP parameter influence. Improvement in fatigue life was demonstrated, and failure of samples at the boundary of the LSP treatment was attributed to a balancing tensile residual stress.
Daniel Glaser; Claudia Polese; Rachana D. Bedekar; Jasper Plaisier; Sisa Pityana; Bathusile Masina; Tebogo Mathebula; Enrico Troiani. Laser Shock Peening on a 6056-T4 Aluminium Alloy for Airframe Applications. Advanced Materials Research 2014, 891-892, 974 -979.
AMA StyleDaniel Glaser, Claudia Polese, Rachana D. Bedekar, Jasper Plaisier, Sisa Pityana, Bathusile Masina, Tebogo Mathebula, Enrico Troiani. Laser Shock Peening on a 6056-T4 Aluminium Alloy for Airframe Applications. Advanced Materials Research. 2014; 891-892 ():974-979.
Chicago/Turabian StyleDaniel Glaser; Claudia Polese; Rachana D. Bedekar; Jasper Plaisier; Sisa Pityana; Bathusile Masina; Tebogo Mathebula; Enrico Troiani. 2014. "Laser Shock Peening on a 6056-T4 Aluminium Alloy for Airframe Applications." Advanced Materials Research 891-892, no. : 974-979.
On the basis of well-known literature, an analytical tool named LEAF (linear elastic analysis of fracture) was developed by the authors to predict the damage tolerance (DT) proprieties of aeronautical stiffened panels. The tool is based on the linear elastic fracture mechanics and the displacement compatibility method. By means of LEAF, an extensive parametric analysis of stiffened panels, representative of typical aeronautical constructions, was performed to provide meaningful design guidelines. The effects of riveted, integral and adhesively bonded stringers on the fatigue crack propagation performances of stiffened panels were investigated, as well as the crack retarder contribution using metallic straps (named doublers) bonded in the middle of the stringers bays. The effect of both perfectly bonded and partially debonded doublers was investigated as well. Adhesively bonded stiffeners showed the best DT properties in comparison with riveted and integral ones. A great reduction of the skin crack growth propagation rate can be achieved with the adoption of additional doublers bonded between the stringers.
G. Molinari; I. Meneghin; M. Melega; E. Troiani. Parametric damage tolerance design of metallic aeronautical stiffened panels. The Aeronautical Journal 2012, 116, 815 -831.
AMA StyleG. Molinari, I. Meneghin, M. Melega, E. Troiani. Parametric damage tolerance design of metallic aeronautical stiffened panels. The Aeronautical Journal. 2012; 116 (1182):815-831.
Chicago/Turabian StyleG. Molinari; I. Meneghin; M. Melega; E. Troiani. 2012. "Parametric damage tolerance design of metallic aeronautical stiffened panels." The Aeronautical Journal 116, no. 1182: 815-831.