Etude Expérimentale et Numérique du Comportement des Murs en Maçonnerie Renforcés par Matériau Composite.

Abstract

There is a large number of old buildings including historical and cultural monuments around the world, which are constructed with unreinforced masonry (URM) and they are exposed to damage due to overloading and deterioration caused by environmental hazards. Therefore, it is highly recommended that adequate retrofit techniques be suggested in order to preserve this type of structure. Different techniques for the reinforcement of URM structures have been proposed, using a wide range of materials such as composite materials. Among the techniques used in the reinforcement of masonry structures, there is the Externally Bonded (EB) fiberreinforced polymer (FRP) technique and the Near-Surface Mounted (NSM) fiber-reinforced polymer (FRP) technique. The main objective of the current study was to investigate the shear behavior of FRP strengthened brick masonry assemblages under in-plane loading. For this purpose, four masonry specimen types were investigated. The obtained results show that, the strengthening techniques had a considerable improvement in shear strength and deformation capacity. In order to model the behaviour of masonry walls, the detailed micro-modelling (DMM) approach was adopted, which is implemented in ABAQUS program to perform a numeric simulation of different masonry assemblages. In this study, finite element models were developed to simulate the behavior of different test types of masonry assemblages. The nonlinearities behavior of brick and mortar was simulated using the Concrete Damaged Plasticity (CDP) constitutive laws. However, FRP strips were connected to masonry elements by interface model. This approach allows failure to occur on either the brick, mortar and brickmortar interface. In addition, the Extended Finite Element Method (XFEM)-based cohesive zone approach was used to simulate the arbitrary crack initiation and crack propagation within a mortar without an initial definition of crack location. The results of numerical simulations were compared with the experimental results. It was concluded that the proposed model presented an excellent prediction for shear behavior and failure mode of unreinforced and FRP-reinforced masonry walls. On the other hand, XFEM was found as a powerful technique to be used for the analysis of the fracture process and crack propagation in masonry walls