Use of composite materials as a new technology

New composite materials are one of the recent techniques for the rehabilitation of structures showing signs of aging, fatigue, failure, overloading, etc. The discovery of fibre materials and the new type of epoxy resin adhesive have allowed the development of new techniques capable of rehabilitating metallic and non-metallic structures in different environments. Recently, FRP materials are used for strengthening steel and concrete beams and structures. In these types of strengthening, shear and delamination forces develop in the bonded structure at the interface of the beam and the FRP plate. The interfacial stresses will develop as a result and a delamination phenomenon of the reinforced structure elements may give rise, and as a consequence may ruin the structure due to the high values of interfacial stresses. The main objective of this thesis is the study of the delamination phenomenon of reinforced beams, The originality of this work is to present an analytical model and a numerical model for the prediction of stresses by itegrating the taper effect and thermomechanical loads under a coupling of prestressing force and hygrothermal effect. This work highlights various parameters, such as geometrical and physical properties, on the stress behavior at the reinforced structure levels.