Análise do comportamento de 3 pontes mistas em obras rodoviárias sujeitas à prova de carga estática

Abstract

Along the BR 230/PA, some bridges had their constructions interrupted about 20 years ago, and with the purpose of providing evaluation criteria to the works of road bridges with mixed structure in steel and concrete is proposed the methodology above. As acceptance criteria, static load tests were used in road bridges with mixed structure through characteristic tests, through instrumentation using strain gauges and LVDT's (Linear Variable Differential Transformer), defining displacements and deformations in the structural elements of the OAE (Special Artwork Bridge), with subsequent computational modeling of the structural model of the bridge, aiming to evaluate the performance of the bridges in service, as established in the structural modeling to the core of the OAE project, which were sized for a type train TB-45 (Type Vehicle of 450 kN of total weight),, according to NBR 7188 (2013). To monitor the displacements, LVDT's were used, positioned in the middle of the span and 1/4 of the span of the central stringers, as well as the strain gage allocated in the steel beams, brace and in the CA-50 steel bars of the pillars with verification of the deformations of the referenced structural parts. As results, an evaluation of the service conditions of the bridge was performed, compressing the experimental results of the static load tests with the theoretical-computational predictions in order to validate the models used, in general, the experimentally observed deformations were less intense than the theoretical estimates. This fact corroborates the agreement with the greater rigidity of the structural elements, validating the experimental results, because they presented behavior similar to the theoretical one, however in lower intensity of the OAE's studied. Thus, the experimental and theoric-computational results were compared with the international norms being the ratios of maximum displacement, residual displacement and deformation. The experimental response showed similar behavior, for the bridges over the Arataú, Anapú and Poraquê rivers, to the theoretically predicted. Inaddition to international norms, the results were divergent, especially in the Turkish, Spanish and German countries, and the boundary conditions imposed on the norms should be imposed.