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Reinforcement using an interlayer system has been demonstrated for more than four decades as a multi-purpose solution to improve performance, to extend service life and thus to reduce maintenance costs of road pavements. Among a large number of existing interlayer systems, glass fibre grids have shown effective use in pavement reinforcement with a hot mix asphalt overlay. Recently they have received increasing attention from the pavement community. However, as for other types of interlayer systems, the mechanisms underlying the effectiveness and proper installation of this type of reinforcement system are still not fully understood, and the choice of the most appropriate grid (e.g. mesh size, tensile strength) and its optimal location in the pavement system are mainly based on experience. This article presents firstly a literature review on the use of glass fibre grids in pavement reinforcement. Then some results of recent full-scale tests on the accelerated pavement testing facility of the IFSTTAR are presented. They confirm that glass fibre grid properly installed near the bottom of the asphalt layer improves significantly the fatigue life of the reinforced pavement. They also demonstrate the efficiency of glass grid use under only a thin asphalt overlay. Finally, first results obtained using an original instrumentation of glass grid strands by means of strain gages, to understand better the mechanical behaviour of the glass fibre reinforcement in a new pavement structure are described

The compressive stiffness of PMMA-based vertebroplasty cement can be reduced to almost a third by the addition of saline. The probable explanation is an increase in microporosity. Future simulator experiments will show whether the achieved reduction in stiffness is large enough to reduce the rate of subsequent vertebral fractures.

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This article examines the determinants of the optimal percentage that private investors seek to invest in a socially responsible (SR) way when forming their portfolio. By conducting a global online survey in English, German and French, we find indications that it is sufficient for the majority of investors to have a certain amount of their budget invested sustainably. Accordingly, the optimal proportion tends to be lower the higher the available investment volume is. In addition, the non-financial utility derived from SR investments appears to be independent of the form of financing the investor provides. Moreover, the results show that well-educated women and slightly younger persons seek to invest a higher percentage of their portfolio socially responsibly.

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Bitumen aging has long been recognized as one of the primary factors that affect pavement's durability. The amount of rheology-based indexes proposed to track the evolution of bitumen aging level underlines their potential for this purpose.Among these phase angle is a powerful tool since it is highly sensitive to changes that occur in bitumen. Hence, this work aims to estimate the aging level of 23 neat bitumens based solely on the evaluation of their phase angle master curve through the application of two multivariate statistical approaches: Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA). PCA score plot displays correctly the studied bitumens according to their aging level, going from left to right, where a marked inflection point is detected along the path taken by the studied bitumen when they age. The groups of bitumens located on each side of this inflection point coincide with the two major clusters obtained through HCA. All the bitumens classified as being in the imminent or cracking zone through the well-known Glover Rowe (G-R) cracking indicator integrate the HCA cluster after the inflection point. The originality of this study lies in the possibility of indicating the aging state and also cracking susceptibility of bitumen based exclusively on the assessment of the phase angle master curve.