Comportamento de pilares mistos, com ênfase na zona de introdução de cargas

Abstract

This work presents the study of composite columns with emphasis on local load introduction zones. The main reason of studying local load introduction zones, here named ZIC, or ZICs, is the need of understanding their behavior not easily found in technical literatures.Experimental analysis with 6 (six) real scale models, elasto-plastics analysis of those tested models, calculation by Eurocode simplified method, and their results are to be evaluated. In this work, 6 (six) real scale models of 3,5m high of partially encased columns are tested in laboratory under axial compression and bending loads, monitored by straingages, dial gages, and DTs. Stresses, strains, slips in concrete and steel interface and displacements are measured for many comparisons. All plotted data, are to be used, not only by numerical models evaluations and comparisons, but also for load distributionand slips between concrete and steel profile and other matters related to ZIC s. Great number of nonlinear elastoplastic models is processed with ANSYS application software. Ansys solid elements named SOLID45 and SOLID65, this last one, with crushing and cracking capability, are used directly with SHELL43 and BEAM189 elements. In all simulations, FEM numerical routines are executed, trying to achieve automatically the ultimate numerical limit states (E.L.U.N). In order to get feasible numerical results in consonance with experimental models, engineering codes and engineering evaluations, modifications are continuously implemented to the numerical models, like adherence simulation presence, or its total absence at steelconcrete interface. Composite columns are one structural solution that joins economy, resistance and fire protection. In most cases, its use, alone itself, or in conjunction with composite beams and or with composite slabs is the ideal solution for many structural steel constructions