Hamco PRIM®
Dipl.-Ing. (FH) Christian Hammes
Dinslaken, February 2021
Corrugated steel structures are characterized by economics, flexibility, high load capacity, durability, a diverse range of application and low to no maintenance costs. The majority of corrugated steel structures are used as water-bearing structures. In this area of application, a so-called, also optically identifiable water-changing-zone forms inside the structure due to changing water levels over time, which, in comparison to the areas that are permantly wetted with water and permantly exposed to ambient air, experiences more intensive corrosion. In the course of decades after the service life has been reached (40-50 years), without any significant maintenance expenditure on the structure with regard to corrosion damages and other circumstances, the water-changing-zone can show a corrosion pattern, which is a consideration of rehabilitating the strcuture. The extent of the corrosion and the related question of the need for rehabilitation is usually dependent on the nature of the water, the frequency of the level changes and the flow rate.
Since the mid-1950s to the end of the 1970s, corrugated steel structures from Dinslaken have mainly been delivered in a hot-dip galvanizing version, which has changed since the 1970s with the use of the Duplex system for Hamco® corrugated steel structures (hot-dip galvanizing plus additional plastic coating).
Due to the fact that water-bearing structures were only hot-dip galvanized from 50-60 years ago, the appearanace described above appears here and there in the water-changing-zone in the structures that are still in use.
In addition to the classic rehabilitation method of concrete and corrugated steel structures, namely by pulling a corrugated steel profile cross-section into the structure to be rehabilitated and the backfilling of the remaining space between the old and new structure, Hamco PRIM® is another eco-nomical rehabilitation method available in the future that ensures the functionality of the original structure for the next deacdes.
Hamco PRIM® describes the partial rehabilitation of the corroded area of the existing structure with the help of a cor-responding shell made of prefabricated corrugated steel parts which optimally follows the course of the existing structure. Then, as with the classic rehabilitation method, the space between existing structure and corrugated steel shell must be filled with an appropriate material.
Compared to the classic rehabilitation method, Hamco PRIM® has advantages in terms of construction time, the lower use of steel material, the lower use of backfill material and, above all, the lower loss of cross-section.
The choice of the two economic rehabilitation methods is determined by the size of the existing structure and/or the altitude of the corroded area.