Industrial heritage revaluation: structural repair of old industrial masonry chimneys

Brick masonry chimneys are the symbol and heritage of Industrial Revolution. They characterize the ski line of many cities and landscapes and bear testimony to the industrial characteristics of an area. Today these structures require conservation: they show loss of verticality and considerable longitudinal cracks due to use. These cracks have deteriorated due to neglect and lack of maintenance. There is no easy solution for repairing brick masonry chimneys because besides the static problems, the architectural integrity and their historical value must be respected. In this paper a method of repairing single flue chimneys is presented. It ensures the structural monolithicity of the chimneys and stabilizes the cracks without damaging its structural integrity. The proposed method consists of inserting a series of steel rings inside the flue for the full height of the chimneys at predetermined distances. These series of steel rings are transversally placed and joined to the wall by anchors and prestressed. To evaluated the overall effects of this method on the stability of the chimney static linear elastic model, using the FEM method, was carried out.