Comparison of environmental benchmarks of masonry and concrete structure based on a building model

Abstract

Construction materials have distinguished energy consumptions and different emissions of carbon dioxide from fabrication up to application. The processes and the treatments needed to transform the raw materials into the final products, the transport to the construction sites and the techniques used for their application, all contribute to the differences in embodied energy and carbon footprint of these materials. In an environmental assessment one wonders what kind of constructive solution is environmentally more favorable. This study refers to the environmental comparison of reinforced concrete and clay bricks. Through a digital three-dimensional building model the required data are analyzed. The building is once considered with a reinforced concrete structure, consisting of columns, beams and slabs, with brick walls in between the columns in the periphery and interior of the building. Then, structural masonry with clay blocks in the exterior and interior walls is studied. Both models are analyzed in two versions. In the first version the slabs are of reinforced concrete and in the second version the slabs are built in pre stressed concrete beams and clay blocks. The building model represents for all solutions equal conditions. The comparison is limited to the quantification of the most important environmental parameters, the embodied energy and CO2 emissions. The results of this study show that the Masonry Model Version 1 has a 11% reduction in CO2 and 12% reduction in energy consumption, while Version 2 of both models has a 39% reduction in CO2 emissions and 41% reduction in embodied energy in case of Masonry Model and 30% reduction in CO2 emissions and 32% embodied energy in case of the Concrete Model compared to the Concrete Model with reinforced concrete slabs. These differences are due to the reduction of reinforced concrete, which is more significant in Versions 2.