Análise comparativa entre projetos residenciais com laje maciça e pré-moldada: impacto no dimensionamento estrutural e no volume de concreto e aço

Abstract

Civil engineering has evolved with the development of new materials, methods, and technologies, making construction processes more precise and efficient. In this context, innovative construction solutions have gained prominence due to the need to reduce execution time and costs in building projects. Given this scenario, the present study proposes a comparative analysis between two structural designs of the same five-story residential building, differentiated by the use of solid slabs and precast slabs, focusing on the volume of concrete and steel consumed. While some studies present comparative analyses of slab systems in isolation, this work evaluates two slab systems considering the behavior of the entire structural set, including foundations, columns, and beams. The objective is to determine the best alternative in terms of material consumption and direct material cost, disregarding labor and execution time. For the development of the study, the projects were modeled using Cypecad© software, following current technical standards and maintaining the architectural layout. From the program, quantitative data for each structural element — foundations, beams, columns, and slabs — were obtained, and a comparative analysis was subsequently carried out based on SINAPI reference values as well as consultations with local suppliers. The results showed that the project with the precast slab presented a concrete volume 0.01% higher and a steel consumption 114.6% lower than the solid slab. Nevertheless, its total cost was approximately 1.73% higher due to the use of metal trusses and EPS blocks, indicating that the solid slab proved to be more economical within the analyzed context.