Fazia Fouchal

An Interface Model Including Cracks and Roughness Applied to Masonry

In this paper an interface model accounting for roughness and micro-cracks is presented and applied to masonry-like structures. The model is consistently derived by coupling a homogenization approach and arguments of asymptotic analyses. A numerical procedure is introduced and numerical results, based on a finite element formulation, are successfully compared with experimental data , obtained on masonry samples undergoing to shear tests. Finally, a parametric numerical analysis is proposed, highlighting the influence of the roughness features on the interface response.

Damage Modeling of Asphaltic Pavement Rough Interfaces Under Tensile and Shear Loading

The interface mechanical behavior in asphaltic pavement structures represents a key parameter for the computational design. Several degradation mechanisms are observed in surface layers due to the de-bonding despite the implementation of tack coats or reinforcing systems. The interface modeling becomes more important in the pavement field during the last ten years, even if this concept is widely studied in composites, masonry structures… Furthermore, the experimental research highlights the sensitivity of the imperfect interface behavior in respect to the underlayer roughness. Due to these concerns, parametrical studies are proposed in this paper, by using a macro scale cohesive zone model. This model allows taking into account the damage behavior of the interface, in pure or mixed mode. Damage mechanisms are governed by internal variables. The numerical results based on a finite element method are compared with experimental tensile and shear data. The geometrical periodic roughness (triangular, crenel) and the mixed mode failure are investigated under monotonic loading. A parametric numerical analysis is presented and shows clearly the roughness influence of these structures.

New Mortar for Clay Masonry Structures

Construction system using timber frame with earth brick infill shows the formation of cracks at their interface with the fluctuation of temperature and humidity. Geopolymer binder has been identified to create good adhesion between these two materials. The aim of the study is to characterize the pullout and shear mechanical behavior of laboratory masonry assemblies of wood, geomaterial binder and extruded earth brick. Compression test on the brick were also performed. Full-field deformation of double shear test sample werecarried-out by digital image correlation (DIC) in order to better describe and understand the mechanical behavior. The geopolymer binder show good adhesion properties with mean shear test results around 1.5 MPa and pullout test result around 0.82MPa.