Eficiência de ligação semirrígida aplicada em concreto pré-moldado

Abstract

The adoption of construction systems, based on precast concrete, is recurrent in structures built in Brazil. With the adoption of precast concrete structures in buildings, that are increasingly slender or that seek a structure with greater rigidity (and, therefore, less occurrence of cracks and deformations in the elements, structural or not), there are considerations necessary in the structural analysis to allow the materialization of the project. The introduction of hybrid connections between beams and pillars is a solution that contributes to the structure stiffening, impacting the redistribution of stresses between its component elements, the displaceability of the structure and the overall stability of the structure. Since the calculation method to obtain the connection's stiffness, to negative bending moment, was included only in the latest version of the Brazilian standard, a comparison was made between two calculation methods: by the displayed in the Brazilian standard and by the Method of Components, in order to analyze how conservative (in favor of security) are the current standard. The present work also studied the effect promoted by this type of connection between elements, thought computer modeling combined with theparametric analysis, in precast concrete structures. The present work looks up for the results of internal forces of bending moment (on beams and pillar base), structure displacements (in service) and global stability (analyzed by yz). coefficient). Also, a study was conducted on the rotation restriction factor (as provided in the standard) of semi-rigid connections, to estimate the bending moment on the ends of the linked beam, with hybrid connections. Finally, it's disposed on the simplifying hypotheses and design parameters adopted, as well as on the applicability (and difficulties) of using the provisions in the Brazilian standards used.