The impact of dust emits by the steel complex of El Hadjar (ANNABA) on two biological models: Mousses and lichens

The effect of the dust rejected by the steel complex of El Hadjar (SIDER) studies was by subjecting the mousses and lichens under a treatment by various concentrations of dust. Previously, the chemical composition of this dust was to analyze and show as well the quantitative and qualitative composition of dust and the dust is consisted of the pollutants with rates much higher than those authorized by WHO. All the measured morphophysiology parameters were strongly disturbed by dust in the case of the mousses and as well as that of the lichens. A clear disturbance of the energy respiratory metabolism was observed at the two species study; these disturbances are related to enzymatic dysfunctions likely to diagnose phototoxicity by certain heavy metals. It was concluded that, the dust rejected by SIDER disturbs the morphophysiology and biochemical parameters of the mousses and lichens and on the other hand, its dust strongly inhibits the two energy phenomena study with known breathing and photosynthesis.Key words: Heavy metals, dust, mousses, lichens, breathing

Behavior of pre-cracked deep beams with composite materials repairs

International audienceThe study covers the behavior of reinforced concrete deep beams loaded under 4-point bending, failed by shear and repaired using bonding glass fiber reinforced plastics fabrics (GFRP) patches. Two rehabilitation methods have been used to highlight the influence of the composite on the ultimate strength of the beams and their failure modes. In the first series of trials the work has been focused on the reinforcement/rehabilitation of the beam by following the continuous configuration of the FRP fabric. The patch with a U-shape did not provide satisfactory results because this reinforcement strategy does not allow to increase the ultimate strength or to avoid the abrupt shear failure mode. A second methodology of rehabilitation/reinforcement has been developed in the form of SCR (Strips of Critical Region), in which the composite materials reinforcements are positioned to band the inclined cracks (shear) caused by the shear force. The results obtained by using this method lead a superior out come in terms of ultimate strength and change of the failure mode from abrupt shearing to ductile bending

Statistical Analysis of 3-Point Bending Properties of Polymer Concretes Made From Marble Powder Waste, Sand Grains, and Polyester Resin

International audienc