Structural health assessment in heavy industries

Structural health monitoring has been a growing business in the past few decades in infrastructure sector, particularly when multi-billion-dollar structures were built. These may include television towers, over hundred storey high skyscrapers, suspension bridges, cable stayed bridges, tunnels and dams. In the industrial sector, owners' mindset has also gradually changed from reactive maintenance to proactive monitoring and preventive measures. In smelting industries, each day of shutdown due to maintenance can cost millions of dollars. This provides the incentive for owners to take the proactive approach to reduce the frequencies and periods of unscheduled shutdowns. In view of the demand, Hatch Ltd. has developed a package for structural health assessment for smelters and various industrial structures. This included a non-destructive testing (NDT) program to identify the weak zones of a structure and a structural assessment to check the soundness of the major-structural components. The non-destructive testing program include the determination of remaining lining thickness or vessel shell thickness, and the determination of the extent of damaged zones and potential runout/leak regions. Furthermore, ground penetrating radar and impact echo are used for identifying corrosion and delamination of reinforced concrete and to locate any voids and cracks within the concrete structures. A case study is provided in this paper to illustrate the effectiveness of the structural health assessment program on silo structures. (author)