Avaliação da resistência de consolos pré-moldados monolíticos e concretados posteriormente ao pilar

Abstract

Precast structures have easy execution and quality control of their elements. However, the connections design is the main problem. Maximum economy in the design is achieved when the connections have adequate performance and quick assembly. One type of connection between column and beam is through corbel. Corbels are structural elements projected from columns to support other parts of the structure. The work presents a literature review about the main concepts that are important to the research. It also contains an experimental program with six small scale specimens with short corbels of the same size. Four models had the same reinforcement rate, different type of anchorage of the tie rod and different conseptions: monolithic or post-installed corbels. Two other models had high reinforcement ratio at the column and low reinforcement ratio of vertical and horizontal stirrups. These two models were monolithic and had different types of tie rod anchorage. Thus, it was possible to evaluate the behavior and safety of monolithic and post-installed short corbels with stirrups in the anchorage of the tie rod. The influence of the stirrups in the anchorage, the contribution of the horizontal stirrup to the strength of the corbel and the influence of the different reinforcement rates of the column and the corbel in the rupture mode were evaluated. All of the specimens presented failure in a ductile manner and ultimate loads higher than foreseen by standards. The calculation models provided ultimate loads closer to experimental ultimate loads because the calculation models consider the contribution of the horizontal stirrups in strength of the corbel. It was found that the stirrups in the anchorage contributed to increase the stiffness of the corbel and that the failure mode of specimens depends on the interaction between the corbel and column reinforcements.