Textile reinforced concrete exposed to aggressive environments

Abstract

The most common reinforcement used in concrete is the conventional steel reinforcement. Although this composite can reach high strengths it can lead to concrete degradation as a result of steel corrosion in certain circumstances. Textile reinforcement is a new- innovative material which has different properties from steel and is currently being introduced to the construction industry. Yet, the longer term durability performance of this new material is not yet known. This study deals with the mechanical properties of textile reinforced concrete (TRC) and its durability performance. The program was focused to determine the difference between textile reinforced concrete samples left to cure under ideal conditions and textile reinforced concrete exposed to accelerated ageing in determining the effects of aggressive environments acting on TRC. Carbon-fibre textile reinforcement and high-performance concrete with a compressive strength of 100MPa were used. Samples were exposed to different temperatures and were cured alkaline solutions in water-tanks under controlled temperature. Tensile testing was carried out on samples having a cross-section of 15x50mm and a 300mm total length. The research further addressed the performance of pre and fresh impregnation of the textile in resin embedded in concrete. In addition, the test samples were also tested in ambient and high temperature conditions during the tensile test itself according to the exposure selected. Both variations in temperature and different alkalinity solution left affects on the resulting yield strengths. The difference between results according to different combinations increased as the Peak strengths was reached. The peak strength reached from the specimen cured initially in a high pH14 solution was 1.2 times higher than the peak strength obtained from the reference sample. As the temperature was increased from 20 to 60 degrees Celsius a resulting decrease of approximately 35% was obtained. The largest reduction in peak strength was detected from the specimen exposed to both elevated temperature and a high alkaline solution. The detected reduction in ultimate tensile strength amounted to approximately 40%, when compared to the reference sample.