Amir Si Larbi

Deterioration of Basic Properties of the Materials in FRP-Strengthening RC Structures under Ultraviolet Exposure

This paper presents an experimental study of the basic properties of the main materials found in reinforced concrete (RC) structures strengthened by fibre reinforced polymer (FRP) sheets with scope to investigate the effect of ultraviolet (UV) exposure on the degradation of FRP, resin adhesive materials and concrete. The comparison studies focused on the physical change and mechanical properties of FRP sheet, and resin adhesive materials and concrete before and after UV exposure. However, the degradation mechanisms of the materials under UV exposure were not analyzed. The results show that the ultimate tensile strength and modulus of FRP sheets decrease with UV exposure time and the main degradation of FRP-strengthened RC structures is dependent on the degradation of resin adhesive materials. The increase in the number of FRP layers cannot help to reduce the effect of UV exposure on the performance of these materials. However, it was verified that carbon FRP materials have a relatively stable strength and elastic modulus, and the improvement of the compression strength of concrete was also observed after UV exposure.

Development of a textile reinforced concrete (TRC) to retrofit reinforced concrete structures

Repairing and strengthening concrete structures with carbon–epoxy composites is of considerable interest; however, there is room for improvement regarding existing methods like bonding of fibre reinforced polymer (FRP). The main objective of this study is to show alternatives to these FRP composites, such as textile reinforced concrete (TRC). Feasibility, performance and behaviour of TRC are examined. A parametric analysis conducted using an experimental approach focuses on the influence of the nature and configuration of the textile reinforcement, the textile reinforcement ratio of the TRC, the pre-impregnation product of the textile and the process for the contact moulding. This study enabled the development of a TRC suitable for repairing reinforced concrete beams by in situ contact moulding. The composite is made of a polymer-modified cementitious matrix reinforced with grids of alkali-resistant glass yarns that are pre-impregnated with a latex-based additive immediately prior to implementation.