Avaliação estrutural e econômica de lajes em concreto protendido e armado convencional em projeto residencial de alto padrão executado na cidade de Curitiba - PR: uma abordagem com o software TQS

Abstract

This study aims to compare the structural performance and economic feasibility of slabs constructed with conventional reinforced concrete and prestressed concrete, applied to the design of a high-standard single-family residence. The choice of theme is justified by the growing use of prestressed concrete in residential buildings and by the need to systematically evaluate in which situations this solution is truly advantageous when compared to the conventional system. For this purpose, two structural versions of the building were modeled using the TQS software, maintaining identical loading conditions, geometries, and normative criteria, thus ensuring an equitable comparison between the systems. The methodology included defining the design parameters, modeling the structural elements, performing the global processing of both models, and verifying the Ultimate and Serviceability Limit States, considering deformations, load distribution, and overall structural behavior. Subsequently, material quantities were extracted from the “Structural Summary” report, including concrete volume, steel consumption, and formwork area. Based on these data, a comparative cost analysis was carried out using SINAPI compositions, enabling the assessment of the financial impact of each solution. The results showed that the prestressed system presented superior structural performance, with reduced deformations and greater efficiency in spanning larger distances, in addition to enabling a reduction in the number of beams and the elimination of intermediate columns. On the other hand, an increase in concrete volume and a significant rise in final costs were observed, due to the higher unit prices of prestressing compositions and the need for specialized labor, although steel consumption was lower. Therefore, it is concluded that prestressed concrete is structurally more efficient but economically less advantageous for the typology studied. The choice between both systems should consider architectural particularities, project standards, and client expectations, noting that, in projects requiring large spans and greater spatial flexibility, prestressed concrete tends to be the most suitable solution.