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in place of the thermosetting organic matrix (usually epoxy) employed for FRP strengthening overcomes some important issues such as the degradation attributable to ultraviolet (UV) and high-temperature exposure and the lack of permeability relative to the concrete substrate.The literature regarding FRCM composites is still very limited, and a comprehensive study of the stress-transfer mechanism in FRCM-concrete joints is not available. The limited number of studies published report that FRCM-concrete joints fail because of debonding of the fibers within the embedding matrix (Carloni et al. 2013;D'Ambrisi et al. 2012D'Ambrisi et al. , 2013a. The debonding process is complicated by the so-called telescopic behavior, a mechanism that leads to a differential slip of the fiber filaments within the fiber bundle principally because of the different matrix impregnation of the outer filaments with respect to the core filaments (Banholzer 2004).The study of the stress-transfer mechanism between the composite and the concrete substrate is of fundamental importance to determine the load-carrying capacity of FRCM-concrete joints. The stress-transfer mechanism between the fibers and the surrounding matrix has been recently studied using a fracture mechanics approach assuming that the shear stresses transferred from the embedded fibers to the two matrix-fiber interfaces are equal (D'Ambrisi et al. 2012;D'Antino et al. 2014). This paper examines this as-sumption and the role of each matrix layer in the stress transfer.

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The chemical composition of the essential oils of Origanum vulgare ssp. hirtum, growing wild in three different localities in the Southern Apennines, was studied by GC-FID and GC/MS analyses. In total, 103 compounds were identified. The oils were mainly composed of phenolic compounds and all oils belonged to the chemotype carvacrol/thymol. The three essential oils were evaluated for their in vitro phytotoxic activity by determining their influence on the germination and initial radicle elongation of Sinapis arvensis L., Phalaris canariensis L., Lepidium sativum L., and Raphanus sativus L. The seed germination and radicle growth were affected in various degrees. Moreover, the antifungal activity of the three essential oils was assayed against three species causing pre- and postharvest fruit decay (Monilinia laxa, M. fructigena, and M. fructicola). At 1000 ppm, the three oils completely inhibited fungal growth. The hemolytic activity of the oils was assayed and showed no effect on the cell membranes of bovine erythrocytes.

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