Estudo comparativo de custo numa residência de 1º andar entre o uso de Laje maciça e Laje pré-fabricada volerrana e treliçada

Abstract

Currently, civil construction requires a constant search for new materials and construction techniques in order to improve the performance of buildings. With the current architectural requirements and the constant search for lower costs, the slabs are being increasingly studied, however, there is still little consistent data to assist in the choice of the structural system to be used in the building works. In order to contribute to the evolution of civil construction, a cost comparison was made for flate plates and precast slabs for a 1st floor residence, considering that they are the two most used methods today in this work pattern. The flate plates have the advantages of a better distribution of efforts in the contour beams and easier installation of the pipes, while the precast slabs are able to overcome larger spans with a lower weight of their own, due to the lower consumption of concrete, and require the use of a smaller number of forms and manpower. The sizing and detailing were performed using structural software and tables. For flat plates, structural software was used and the heights of each slab were obtained, as well as the reinforcement and its dispositions. For precast slabs, ceramic tiles were adopted and divided between ceiling slabs and floor slabs, using one way ribbed slabs and lattice slabs for each type of use, respectively. For the dimensioning of one way ribbed slabs, tables available in Cunha and Souza (1998) were used, while for the lattice slabs it was used the aid of GERDAU Trusses Software, where the total heights, joists, ceramic bricks and capping heights were obtained, as well as the inter-axes. After the sizing was completed, budgets were made with the help of tools that define the values of the inputs and services required for engineering works and services, where the values were adopted without tax relief. For flat plates and one way ribbed slabs, the Secretaria de Infraestrutura’s (SEINFRA) Table of Costs was used, 026 edition, while for the lattice slabs, the table of Companhia Paulista de Obras e Serviços (CPOS), March 2018 edition, was used. The result obtained was a 38.08% lower value for precast slabs compared to flat plates, largely due to the use of a smaller volume of concrete, less manpower and a reduced number of shapes.