Análise da influência da espessura de lajes lisas no comportamento global de edifícios

Abstract

The structural flat plate system presents several advantages; however, it requires a more cautious analysis regarding the stability to horizontal actions, especially for multiple-storey buildings and also, in relation to the punching shear in the slab-column connection. The slabs are important in the distribution of the load generated by the wind between the bracing elements, since they have practically infinite stiffness in their plane, thus promoting the bolting of the structure. Therefore, in order to create subsidies to guide the use of slabs in multi-floor buildings and to apply the advantages of this structural system, this work had as objective the study of the influence of slab’s thickness on the overall behaviour of the building, as well as the influence of the number of floors of the building. A review of the calculation methods for the verification of the slabs to punching shear was provided according to the codes ABNT NBR 6118: 2014, Eurocode 2: 2004, ACI 318: 14 and EHE-08. However, the structural analysis was done analytically and using a computational tool, based on the recommendations of ABNT NBR 6118: 2014. Although the parameter of stability against the lateral actions analysed (FAVt) was slightly modified by the change of the slab thickness, it growth as the number of floors increased, and the same was noticed for the horizontal displacements. The vertical floor deformation was significantly reduced with increasing slab thickness, as well as the slab behaviour due to punching was optimized.