DAMAGE EVOLUTION IN COMPOSITE BONDED JOINTS UNDER FATIGUE LOADING
In the present paper the evolution of fatigue damage in composite bonded joints is extensively analysed and discussed, with particular reference to the influence of layer orientation at the adhesive-adherend interface, corner geometry at the end of the overlap area and stacking sequence. Single lap bonded joints manufactured from autoclave-moulded laminates were investigated under tension-tension fatigue loading. Two laminate lay-ups [45/02]s and [452/0]s , two overlap lengths (20 and 40 mm) and two corner geometry (square edge and fillet) were considered. The evolution of fatigue damage, a crack initiation followed by propagation up to a critical length, was investigated at macroscopic and microscopic level, by monitoring stiffness trends and by optical and scanning electron microscopy and it is extensively discussed in the paper. The presence of a 45° oriented layer at the adhesive-interface layer makes damage patterns and crack paths much more complicated with respect to 0° interface joints, previously investigated by the authors. As a result the resistance to crack propagation is increased.
Composite adhesive joints under cyclic loading
Abstract With the increasing use of adhesive bonding in structural joints in many applications, the interest in the behaviour of adhesive joints under cyclic loading has increased as well. Much work has already been performed on the analysis of adhesively bonded joints under static loading. Also the damage growth and failure mechanisms of adhesive joints under cyclic loading has been investigated, to a less extent for joints in composite structures. A major difficulty is the large amount of parameters that can be of influence on crack initiation and growth in adhesive joints. This makes it hard to characterise the debond behaviour of a joint. This article is intended to give an overview of studies performed on adhesive composite joints under cyclic loading on and to serve as a starting point for designers who need information on experimental and analytical methods of composite adhesive joints.
Gender Pay Gap in the European Union Labor Market
The participation of women in the European Union labor market has been increasing over recent years, putting an end to the notion that women are a marginal part of the labor force. However, such increased integration of women into paid work has neither ended the traditional gender divide between jobs nor it translated into gender equality in terms of economic opportunity and economic participation in the labor market. The purpose of the paper is to briefly discuss the gender pay gap in the EU labor market. The paper defines gender pay gap and provides a brief theoretical overview of the underlying causes of such pay asymmetry between men and women. Statistics provided for EU 25 reveal that the current policy attempts to reduce such a gender asymmetry still lack improvement in practice. The paper concludes with selected policy suggestions aiming to make a progress in the issue of the gender equality in pay.