Manifestações patológicas em viadutos de concreto armado : estudo de caso de 4 viadutos na cidade de Belo Horizonte

Abstract

Viaducts are important special works of art for the movement of people and the flow of cargo, providing greater fluidity to traffic in large urban centers. Although they are important elements of this type of transportation, a high number of pathological manifestations can be observed in this type of reinforced concrete structure, often related to careless maintenance and conservation by the managing agencies. This study has the objective of identify the most recurrent pathological manifestations in reinforced concrete viaducts, as well as the deterioration mechanisms and how failures in maintenance activities interfere in the performance and in the reduction of the lifetime of these structures, through inspections performed in four viaducts in the city of Belo Horizonte. These activities were carried out based on the prescriptions of the NBR 9452 technical standard of the Brazilian Association for Technical Standards (ABNT) and with the support of the following tools: camera, fissurometer, bubble level and thermographic camera. The OAE's inspected presented a series of pathological manifestations and, therefore, regular or poor conservation status of the constituent elements based on the structural, functional and durability parameters exposed by the technical standard mentioned above. In general, the vast majority of anomalies were related to failures of watertightness of the structures resulting from failures in the maintenance of works of art, either by lack of continuity of drainage pipes, failures in the connection between the devices, water collection points obstructed with garbage and, especially, failures in the sealing of expansion joints. That is, the emergence and evolution of most pathological manifestations identified are related to maintenance and use failures that corroborate for the early deterioration of the structures, interfering in the fulfillment of the requirements of use, such as structural safety, functionality and durability.