Pegada hídrica na construção civil : uso e impactos de alvenarias

Abstract

Masonry are elements responsible for the vertical sealing of buildings, they can consist of different blocks and bricks, and they need different amounts of inputs. Masonry production has different water consumption for elements that perform the same function, even with different uses. Then, the accounting of water consumption of masonry allows comparisons. Thus, the objective of this research was to calculate the blue water footprint (PHblue) of three different masonry, in order to identify the masonry that has the best water performance - the lowest water consumption, and to identify inputs with a major contribution to the process of masonry production. Based on the SINAPI unitary compositions, the necessary inputs for the realization of one square meter of each masonry were identified and quantified, considering or not mortar coating. Then, a bibliographic survey was carried out to collect data on water consumption of intermediate products (PHblue,indirect) and water consumption in the preparation of mortars (PHblue,indirect), enabling the calculation of water consumption by material, by PH component. and masonry. Consumptions of 67.64 L m-², 75.05 L m-² and 270.85 L m-² were identified when not covering the masonry of perforated ceramic block - CF, solid ceramic brick - CM and concrete block - BC, respectively. Considering mortar lining, consumptions of 364.02 L m-², 371.43 L m-² and 567.24 L m-² were identified for masonry blocks CF, CM brick and BC respectively. The mortar coating was responsible for a large part of the water consumption in the masonry (from 52.25 to 81.42% of PHblue), resulting in 296.38 L m-² of masonry. PHblue, indirectly corresponded to the higher water consumption of masonry and mortar coating.