Estudo comparativo entre o método dos pórticos equivalentes e o método dos elementos finitos para análise de lajes nervuradas.

Abstract

Due to the increasing use of large spans, waffle slabs have been increasing, euplayed based on large-span is more required. Thus, waffle slab has been used as subject of researches in order to improve he procedures for determining their solicitations. The ACI Method, for Equivalente Framework, establishes a simplified calculation model, which is applied to slabs that have columns with regular arrangement, providing the distribution of bending moments in bands. The Finite Element method is increasingly used for structural analysis, as it is a good indicator of the actual behavior of the structure and, therefore, increases the accuracy of the analyzes. Thus, this work seeks to develop a comparison between the cited methods for the analysis of waffle slabs. In addition, a waffle slab was dimensioned and detailed using the requests obtained through the normative specifications. For these applications, the floor of a store building composed of smooth waffle slabs was defined as a model. For the application of the Equivalent Framework Method, a central porch was defined for each direction of the slab and, later, the same were launched in the software Ftool, through which the cutting forces and characteristic bending moments were obtained. From these, the method was applied, the dimensioning and the detailing of the model slab. For the application of the Finite Element Method, the model was simulated using the software ANSYS 16.1, through which the normal stresses incident on the slab were obtained and, subsequently, the respective bending moments. Finally, the bending moments obtained through both methods were compared and a significant difference was found between them, and those obtained through the normative method were higher.