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This paper presents an experimental study to characterize the mechanical behaviour, at the local scale, of sound and degraded concrete after leaching. An experimental protocol was developed to study the effects of the calcium leaching mechanism at the interfacial transition zone (ITZ) on the mechanical properties of the cement-aggregate interface and bulk paste of model material. The process of lixiviation with deionised water occurs very slowly. The experimental study in the laboratory was accelerated by replacing the water with an ammonium nitrate solution. To quantify the development and kinetics of degradation at the cemented bond, the concrete leaching fronts were characterized at different levels of degradation using phenolphthalein and local mechanical tests (compression and tensile) and performed on samples consisting of two aggregates bound by cement paste. Tests were performed on sound samples at different hydration times and on chemically degraded samples. The results show the effect of leaching on the mechanical properties of the samples and making it possible to correlate the progress of leaching to the evolution of these locally considered properties. The experimental results show that there is an ITZ effect on the alteration of the mechanical properties due to leaching.

The Atlas cedar is an endemic species of the African North Mountains. The goal for which this work was conducted is to determine the chemical composition and to study the antibacterial and the antifungal activity of the hydrodistilized essential oil from both the winged and wingless seeds of the High Atlas Cedrus atlantica (Morocco). The essential oil is analyzed by gas chromatography and gas chromatography mass spectrometry. The essential oil yields of winged as well as wingless seeds were respectively 2.6% and 3.6%.The main constituents of the cedar wingless seeds are the α-pinene, the manool, and the bornyl acetate; whereas, the major constituents of the cedar winged seeds are the manool and the α-pinene. The antibacterial and antifungal activities of the essential oils were tested on four bacteria, three molds and four fungi of wood rot. The fungal strains tested were revealed more sensitive to the essential oil studied than the bacterial strains.

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