DEGRADAÇÃO DO CONCRETO: ANÁLISE DA EFICÁCIA DE AGENTES PREVENTIVOS

Abstract

Concrete is the second most consumed material by civil construction in the world, mainly due to its great initial fluidity in the fresh state and high mechanical resistance in the hardened state. Despite the wide use of the material, the number of collapses involving the durability of reinforced concrete structures is still recurrent. On the other hand, in Brazil, there is still no specific standard for assessing the useful life and durability of concrete. Most of the pathological manifestations present in reinforced concrete structures are linked to the aggressiveness of the insertion medium and the material's vulnerabilities in the face of it, with expenditure on corrective repairs being highly critical and costly. In view of these concerns, the present work aims to compare the performance of the preventive agents silica fume and nanosilica, pore blockers and epoxy acrylic resin, in terms of durability, with regard to the pathological manifestations that usually affect the structures of reinforced concrete, namely: reinforcement corrosion due to chloride attack, carbonation and abrasion wear. For this, a literature review was carried out. Research by different authors was selected and specifically addressed the following tests: Abrasion Los Angeles, accelerated carbonation, chloride diffusion and electrical resistivity, for concretes prepared with and without the selected preventive agents. Surveys were selected, read, and the results compared and analyzed. In the end, based on the results, it was possible to verify the best preventive method adopted for the selected aggressive agents, classifying the joint action of two agents evaluated as the most effective and viable prevention, in order to prolong the useful life of the structures and minimize rework costs on repairs.