Estudo sobre aderência entre barras de aço e concreto autoadensável com baixo consumo de cimento

Abstract

Cement consumption at global level increases gradually, so too grows the environmental degradation that the construction generates. In this scenario, the search for rationalization of materials becomes important. Self-compacting concrete with low consumption of cement (SCCLCC) part of the concept to achieve sustainability in construction, as it provides longevity of deposits of raw materials and reduction in emission of CO2. Being self-compacting, confers on this concrete characteristics in its fresh state, such as: resistance to segregation, passing ability, fluidity and workability. In order to check the use of SCCLCC as a structural concrete, this research assessing the influence of low cement consumption in relation to the bond behavior between steel bar and concrete. Therefore, this research is characterized as a theoretical and experimental study of steel-concrete bond, using SCLCC. For this study, tests were performed with pullout test following the model shown by RILEM-FIP-CEB (1973). The variables studied were: the concrete, which compared the bond behavior between reference self-compacting concrete (RSCC) and the SCCLCC, being used three doses SCCLCC with reduction of 17.5%, 20,0% and 25,0% of cement in relation to the reference concrete and, the steel bar diameter (10 mm and 16 mm). Also, compared the results of bond behavior with bond forecast for formulations of some regulatory codes and theoretical models employed in the literature scientific technique. According to the results, the bond behavior of the SCCLCC was similar or superior to the RSCC, reduced consumption of cement in concrete composition did not influence negatively the bond behavior, as well as other mechanical properties. Regarding theoretical models, there was no satisfactory convergence of the results, demonstrating the need for further studies to predict theoretically the behavior of the bond tension.