STRUCTURAL SURVEILLANCE, ASSESSMENT OF STRUCTURAL CONDITIONS AND REHABILITATION OF AN INDUSTRIAL PLANT Deterioration due to chlorides

摘要

Typical concrete shell structures built in Norway after the 2. World War are described. These structures represent a part of Norway's post-war development and contributed to the rise of the industry and the welfare of the nation and its inhabitants. At the time focus was put on functionality and economy, not realising the necessity to prohibit the deteriorating processes of reinforced concrete known today to occur. Typically the durability aspects were not prevailing neither for mix design, nor for design or execution. General aspects for the design and execution of these structures are presented. Comments to design assumptions and execution are given as well as to applied methods for repair. The challenges involved when approaching these structures today are exemplified by presenting the restoration of a factory owned and operated by Orkla Exolon KS in Orkanger, Norway. Here a new shell roof was constructed on top of the old one, offering only a minimum of interference with the industrial production (process). The importance of overlooking both the condition of original structural components and materials as well as the structural integrity is pinpointed as the key factor for success in the end.