Mammoet navigates transport paths for pipe rack placement

Mammoet was tasked with the transport and setting of six pipe rack modules across a variety of existing infrastructure in the Hartford, IL region. This included four lanes of Illinois Highway 3, the Mississippi River levee and five railroad tracks owned by various operators. The customer wished to assemble all modules at lower elevations and requested that Mammoet jack the modules up to the required elevation before transport and setting.

Aerial view of pipe rack module transport

Mammoet’s method of utilizing Self-Propelled Modular Transporters (SPMTs) allowed the modules to be assembled onsite without impact to the surrounding infrastructure, the company said. Building at a lower elevation presented safety advantages as it minimized the need for crews to work at height. To further minimize traffic and rail disruptions, transports took place during off peak hours (nights and weekends) and were safely completed within the allowable highway or railroad closure limitations.

The Unit 2 module, a span measuring 314 feet long and weighing 296 tons, presented multiple transport challenges. It required Mammoet’s operators to navigate a blind turn as the pipe rack straddled the levee, meaning the two SPMT operators were unable to see each other. To exit the laydown yard, the trailers began in the transverse direction, then after a short transport of approximately 100 feet, the trailers then turned 90° and traveled south down the highway where the first trailer made a 90° turn to pass through the 20-foot wide levee gates.

Then, with power lines and support poles interfering at the south end of the travel path, a 90° turn to the north called for the second trailer to move in reverse. As the module moved north, it approached a temporary staging position on the west side. Using hydraulic gantries to support the load, the SPMTs were repositioned to navigate the narrow travel path, allowing for final set. Once the front trailers were repositioned, the piece was then transported the final 50 feet and set on supports where it spanned access roads on either side, the levee and a divided 4-lane highway.

Aerial view displaying complex turns and obstacles along transport route

The installation of Unit 5 also presented significant transport challenges, including negotiation past an existing substation, under high voltage power lines, and across multiple railroad lines. There were also subsurface conditions and monitoring wells that could not be loaded, which added to the complexity of the available haul route.

The rail owners approved Mammoet to bridge the tracks with roll-on roll-off (RORO) ramps, but only allowed for a narrow window of track closure to install the ramps and execute the transport operation. As with Unit 2, the final transport required the use of hydraulic gantries to reposition both trailers prior to final set, in order to mitigate the multiple haul route interferences.

All modules were jacked up using Mammoet’s JS500 self-climbing jacking system approximately 30 feet from assembly elevation to set elevation. Each pipe rack was transported at either end with double 9 axle-line SPMTs, a falsework arrangement, turntables and 300-ton Mega Jack towers.

Watch the maneuver here