Comparative assessment of the environmental impact of paving types: asphalt, concrete and blockpavers, used in causeways of residential neighbourhoods in the city of Mendoza, Argentina

ARENA, AP; CORREA, E; DE ROSA, CARLOS

Brisbane

Conferencia; LCA THIRD AUSTRALIAN CONFERENCE; 2002

Australian LIfe Cycle Assessment Society

The construction of streets involves the use of materials of high energy cost, such as cement, and others which are non renewable, for example bituminous compounds and gravel, the latter usually extracted from river embankments that represent high landscape value. The processes involved in the extraction, production and transportation of these materials consume huge quantities of non renewable energy resources and emit enormous quantities of solid, liquid and gaseous pollutants. During the paving process, heavy machinery, with very powerful engines are used, which implies more energy consumption and release of pollutants. Maintenance and repaving activities generate enormous volumes of solid wastes, which being chemically inert cannot be reprocessed by natural ecosystems. From the viewpoint of the urban environment, the infrastructure of circulation networks, both pedestrian and vehicular, presents itself as an ensemble of components of unquestionable relevance, since their quantitative incidence over the total urban area is highly significant. For instance, in traditional gridiron urban areas, the vehicular causeways occupy 15.9% of the urban soil, and in rectangular layouts as commonly used in social housing neighborhoods, this value reaches 22.6%. Despite this stern picture, the construction of streets has not received enough consideration from a sustainability point of view. The goal of this study is to evaluate the environmental performance of concrete block pavers used in the construction and maintenance of residential streets as compared with the more traditional poured-in-place (in situ) concrete and asphalt paving types. These three paving types cover almost 100 % of the total paved surface in Mendoza´s residential streets. For the evaluation of the environmental impact an abridged Life Cycle Assessment (LCA) procedure has been used, including all materials and processes involved in the construction and maintenance of every paving type. Due to the lack of information, end-of-life management has not been included in this study. The functional unit considered is a stretch of 960 m2 of street (100 m length), located in the Central Park area in the City of Mendoza.