By: TrueNorth Steel
TrueNorth Steel was contacted about an application in which three vertical monopoles, approximately 50 feet in length, were being constructed in northern Minnesota to support a large conveyor system that would soon be transporting pellets for taconite processing.
TrueNorth Steel conducted pre-construction meetings to discuss the pad and pier foundation, concrete pouring process, and the structural rebar reinforcing cages that were being used on the outside of the vertical pipes. Ultimately, TrueNorth Steel worked to determine that a 5″ x 1″ corrugation 90″ diameter corrugated steel pipe (CSP) would function well for this undertaking.
A unique aspect of this project was that each of the three monopoles utilized two segments of CSP which had to be manufactured with strict length, outside diameter, and height tolerances to fit inside of the custom rebar cage.
Though the pipes could have been fabricated in one piece, site conditions dictated that each monopole consist of two pipes and a band. Despite a short turnaround schedule, TrueNorth Steel was able to meet the contractor’s aggressive installation timeline and support the customer with multiple site visits.
As an added service, TrueNorth Steel also prepared as-built drawings that clearly outlined the specific labeling strategy (critical to ensure all the pipes were properly orientated) along with the fabricated dimensions of each component. This level of detail was critical to the success of the project since the pipes had to be inserted into two larger diameter rebar cage cylinders. Each pipe had custom weld-on lifting lugs designed for a crane pick and placed so that the lugs did not interfere with the other components of the pier support assembly during the installation process.
TrueNorth Steel’s customized approach and attention to detail achieved the customer’s goals and kept the project on schedule.
