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Fuselage structures are subjected to combinations of axial, bending, shear and differential pressure loads. The validation of advanced metallic and composite fuselage designs against such loads is based on the full-scale testing of the fuselage barrel, which, however, is highly demanding from a time and cost viewpoint. This paper aims to assist in scaling-down the experimentation to the stiffened panel level which presents the opportunity to validate state-of-the-art designs at higher rates than previously attainable.

Development of a methodology to successfully design tests at the stiffened panel level and realize them using advanced, complex and adaptable test-rigs that are capable of introducing independently a set of distinct load types (e.g. internal overpressure, tension, shear) while applying appropriate boundary conditions at the edges of the stiffened panel.

A baseline test-rig configuration was developed after extensive parametric modelling studies at the stiffened panel level. The realization of the loading and boundary conditions on the test-rig was facilitated through innovative supporting and loading system set-ups.

The proposed test bench is novel and compared to the conventional counterparts more viable from an economic and manufacturing point of view. It leads to panel responses, which are as close as possible to those of the fuselage barrel in-flight and can be used for the execution of static or fatigue tests on metallic and thermoplastic curved integrally stiffened full-scale panels, representative of a business jet fuselage.

The present study deals with the numerical modeling of the low-velocity impact damage of laminated composites which have increasingly important applications in aerospace primary structures. Such damage, generated by various sources during ground handling, substantially reduces the mechanical residual performance and the safe-service life. The purpose of this paper is to present and validate a computationally efficient approach in order to explore the effect of critical parameters on the impact damage characteristics.

Numerical modeling is considered as one of the most efficient tool as compared to the expensive and time-consuming experimental testing. In this paper, a finite element model based on explicit dynamics formulations is adopted. Hashin criterion is applied to predict the intralaminar damage initiation and evolution. The numerical analysis is performed using the ABAQUS® programme.

The employed modeling approach is validated using corresponding numerical data found in the literature and the presented results show a reasonable correlation to the available literature data. It is demonstrated that the current model can be used to capture the force-time response as well as damage parameter maps showing the intralaminar damage evolution for different impact cases with respect to the physical boundary conditions and a range of impact energies.

Low-velocity impact damage of laminated composites is still not well understood due to the complexity and non-linearity of the damage zone. The presented model is used to predict the force-time response which is considered as one of the most important parameters influencing the structural integrity. Furthermore, it is used for capturing the damage shape evolution, exhibiting a high degree of capability as a damage assessment computational tool.

The purpose of this paper is the development and the assessment of detailed and macro-modelling methodology approaches, suitable for the analysis of composite material bolted joints.

A benchmark single-lap, single-bolt composite joint configuration is investigated, in order to demonstrate the different joint analysis approaches which are applicable in advanced riveted/bolted parts of aeronautical structures. In particular, several joint macro-models, i.e. numerical and analytical ones, as well as a detailed three-dimensional FE solid joint representation, were developed and compared in terms of stiffness prediction, while they were validated using respective experimental results. In addition, the numerical macro-model is implemented in a full scale, multi-bolt fuselage panel in order to demonstrate its capability to efficiently predict the panel’s response under compressive loads.

Good correlation was observed between the majority of the models’ predictions and the relative experimental data regarding the lap joint configuration, while the simplified numerical macro-model showed some discrepancies due to the contact instabilities, which, however, may be accepted taking into account the remarkable solution time reductions. In the same manner, the FE macro-model illustrates sufficient accuracy in the prediction of the panel’s response, while, simultaneously, it maintains a low CPU time.

The present study is part of Nikolaos Perogamvros’ doctoral thesis, an original research work. There are very limited literature papers which include the development and the assessment of different efficient and detailed composite joint analysis approaches, regarding their accuracy and efficiency in the stiffness prediction of a composite bolted joint configuration, as well as on the prediction of a multi-bolt panel’s response.

The purpose of this paper is to analyze the bird impact damage of fuselage composite stiffened structures by numerical method and to evaluate the damage and the bird impact resistance of different structures.

The deformation and damage of composite stiffened plates during bird impact are numerically analyzed by the explicit finite element software LS-DYNA. A comparative study on the numerical calculation results was conducted by using SPH (Smoothed Particle Hydrodynamics)-FEM (Finite Element Method) modeling and simulation. First, the I-shaped, T-shaped, straight stiffened plates and unstiffened plate were designed. Second, the accuracy of the bird model was verified and further used to evaluate bird strikes on composite stiffened plate. Third, the results of damage modes as well as displacements of the stiffened plates were compared.

The stiffeners can increase the local stiffness of the composite panel, which can effectively inhibit the bird’s movement along the impact direction. Adding stiffeners can change the panel matrix tension damage from global distribution to local distribution mode; however, the impact damage distribution and the ability to inhibit damage propagation can differ for different stiffened panels. Especially, the I-stiffened panel exhibits a better anti-bird strike performance.

The analysis of geometric parameters of structural components by numerical methods can reduce the cost of the design phase and has been widely used in aircraft design. The present study evaluated the bird impact damage of composite stiffened plates with different structures, which provides a guideline for selecting the stiffened plate structure in the fuselage skin.

The purpose of this paper is to investigate the ballistic impact response of square clamped fiber-metal laminates and monolithic plates consisting of different metal alloys using the ANSYS LS-DYNA explicit nonlinear analysis software. The panels are subjected to central normal high velocity ballistic impact by a cylindrical projectile.

Using validated finite element models, the influence of the constituent metal alloy on the ballistic resistance of the fiber-metal laminates and the monolithic plates is studied. Six steel alloys are examined, namely, 304 stainless steel, 1010, 1080, 4340, A36 steel and DP 590 dual phase steel. A comparison with the response of GLAss REinforced plates is also implemented.

It is found that the ballistic limits of the panels can be substantially affected by the constituent alloy. The stainless steel based panels offer the highest ballistic resistance followed by the A36 steel based panels which in turn have higher ballistic resistance than the 2024-T3 aluminum based panels. The A36 steel based panels have higher ballistic limit than the 1010 steel based panels which in turn have higher ballistic limit than the 1080 steel based panels. The behavior of characteristic impact variables such as the impact load, the absorbed impact energy and the projectile’s displacement during the ballistic impact phenomenon is analyzed.

The ballistic resistance of the aforementioned steel fiber-metal laminates has not been studied previously. This study contributes to the scientific knowledge concerning the impact response of steel-based fiber-metal laminates and to the construction of impact resistant structures.

To study the corrosion resistance of the novel alloy Al‐12.6La (wt%) manufactured using directional solidification.

Samples fabricated using the Bridgman growth technique at three different withdrawal velocities were subjected to total immersion tests in distilled water and in 3.5 per cent NaCl solution and to DC polarisation tests in distilled water. XPS analyses conducted on samples after polarisation indicated the presence of an La compound in the non passive corrosion products film formed.

Anodic polarisation induced dissolution of the alloy with the formation of a non passive corrosion product film. During potentiodynamic polarisation, a sudden current increment occurred at a potential value that was more positive for samples solidified at higher rates. The corrosion resistance of this Al‐12.6%La alloy decreased as the solidification rate increased.

The results presented in this work are an insight to the understanding of the corrosion resistance and electrochemical behaviour of this alloy for future engineering applications and development.

The purpose of this paper is to propose that interprofessional working between professionals who work with people living with HIV (PLWHIV) contributes to improvements in the health, social care needs and long-term outcomes of PLWHIV. Interprofessional working initiatives have been useful in promoting successful frameworks used towards improving various aspects of the HIV disease family planning and transmission prevention. The paper proposes that interprofessional working is important in elevating stigma and discrimination that sometimes prevent PLWHIV from successfully achieving parenthood through adoption. The objective of this study is to contribute to social work practice and literature that supports adoption.

This paper draws on an interpretative phenomenological analysis (IPA) study looking at the experiences of PLWHIV going through the adoption process. The study relied on in-depth interviews with six PLWHIV who had gone through the adoption process and presented views regarding a need for better collaborative working by those assessing PLWHIV going through adoption. The sample was purpose and homogeneous. Interviews were recorded, transcribed and analysed using IPA framework. Transcripts had been written up and analysed individually. Following which a cross-case analysis to create meaning and conceptual understanding that was common among all cases.

Drawing on themes around interprofessional working, this paper argues that there is a need for improved and transparent interprofessional working models within adoption systems. The paper provides conceptual understanding around interprofessional working and how this can be brought about to support the needs of PLWHIV seeking to adopt children. It proposes that working in isolation will leave PLWHIV feeling that the adoption process is ambiguous and unfair, yet efforts to combat this are evident in healthcare settings.

Limitations to this study include an acceptable but small convenience sample within IPA methodological approaches. This is a hard to reach sample and results may not be generalisable.

This paper opens a dialogue for discussing issues around the adoption for PLWHIV and informing professionals about increasing opportunities for PLWHIV to adopt children where there is a high demand for adoptive parents.

Placing the views of participants in this study within the body of knowledge could influence meaningful collaboration between adoption social workers and those supporting PLWHIV within health, social care and voluntary sectors. This may influence change and reduce stigma and barriers preventing some PLWHIV from successfully adopting children.

This paper meets an identified need to explore how PLWHIV can be supported to achieve parenthood. The paper expands on existing knowledge around the need to provide fertility treatment to PLWHIV. It suggests that child adoption can be promoted through child adoption and ultimately promoting normalcy around the desires of PLWHIV to achieve parenthood using non-traditional methods of conception.