Determinação de parâmetros ambientais para o dimensionamento otimizado de estruturas em concreto armado

Abstract

In Brazil, reinforced concrete is currently one of the most used materials in the construction of building structures and big road infrastructures such as bridges, viaducts, pedestrian bridges and so on. Its widespread use results from the great execution ease and adaptation to many forms. One of the ways to search greater sustainability in construction industry is to reduce consumption of materials involved in the production of reinforced concrete, consequently reducing its cost. These reductions in materials consumption and costs, if evaluated under the impact their production generates in the environment, can come to enhance or redirect conclusions or decisions to be taken concerning the search for a higher environmental sustainability. Under this focus, the present study is elaborated. The objective is to quantify and evaluate the emission of carbon dioxide (CO2) and the electric energy consumption, and also the environmental impacts generated when extracting and producing materials (agglomerant, coarse aggregates, crushed aggregates, and steel) used in the north of the state of Rio Grande do Sul, in the production of reinforced concrete. The environmental impacts generated in the transportation of these materials to the place of their utilization are also evaluated, i.e., from the concrete batcher and the transportation to the building site. In a second phase, the use of these materials through the dimensioning of reinforced concrete beams was optimized, taking into account not only cost reduction but also the reduction of environmental impacts in its generation and transportation. The obtained results indicate meaningful final results in the emission of CO2 related to transportation. Yet, in the choice of concrete resistance, the use of smaller resistance presents a better result in relation to reduction of CO2 emission, electric energy consumption, and in costs, even if with a bigger resistance there is a decrease in the volume of the used materials