Análise de lajes nervuradas unidirecionais submetidas à esforço cortante.

Abstract

The present work analyzes resistance criteria for shear effort in ribbed slabs, by comparing theoretical models with results obtained experimentally, with the purpose of contributing to the study for the constructive system of ribbed slabs. For this work, tests were carried out on four ribbed slabs, concreted as a "T" section, formed by the rib containing the traction armature and the concrete cape, in order to determine the load that leads to the shear stress rupture of these slabs. For the shear tests, the slabs defined with a length of 50 cm were positioned on two movable supports and loaded at two points to one third of each end of the test vain. From the results obtained in the experimental analysis, where the load was resisted by the slabs until their rupture, it is possible to compare them with the values of theoretical models. These, in turn, were calculated using the recommendations of the spanish norm EF-96 and NBR 6118:2014, which analyzes the shear effort of calculation for elements without armature for shear effort, and to the ruin of compressed diagonals of concrete. At the end of this study, after the analysis of the results obtained, it was possible to present conclusions about the calculation models compared with the experimental tests. On the basis of the tests and calculations, the obtained results indicate that in a usual slab, it is far from crushing concrete, because the shear of the structure occurs before.