Análise comparativa da distribuição mais econômica de vigas mistas de aço e concreto, considerando a vibração devido ao caminhar de pessoas e altura mínima de laje para segurança contra incêndio

Abstract

The composite steel-concrete system presents great advantages of use compared to other construction systems. One of the most decisive points for using this type of constructive system is the possibility of floors with large spans without shoring and great speed in the execution of the construction, however the cost of application of this constructive model still limits the use in small buildings. The purpose of this work is to design the most economical structure possible by the analysis and treatment of the design results of typical shop and office floors presented in the literature , in order to compare and evaluate if they meet the floor vibration criteria for walking excitations and the design criteria for composite slabs in fire situation. In addition, two design methods that meet the aforementioned criteria are proposed and validated, resulting in a lighter structure possible and, consequently, more economical. With the help of calculation worksheet, the typical floors presented by previous works were redesigned and two calculation methods were proposed, A and B, which consist of verifying the behavior of the structures when the vibrations of the main and secondary beams in different configurations and situations where the considered profiles are as light as possible. The results demonstrated that the proposed methods resulted in more economical structures than those presented by previous works. For typical office floors, between methods A and B, method B demonstrated to be more economical in most dimensioned cases, but method A had a better relationship between span and height of the beams and little percentage difference between the final weight of the method B. As for the typical shop floors, there was no difference in dimensioning between the methods.