Mammoet has again displayed its heavy lift and logistical prowess and helped the construction efforts at Portland International Airport by jacking up, transporting, and installing a series of roof panels.
The airport, known as ‘PDX’, is scaling up its capacity to nearly double its size as it seeks to better serve and facilitate the 35 million passengers who commute through the space annually. One of its key components is the construction and installation of a new, seismically isolated roof structure as a large fault line exists next to Portland.
The seismically isolated roof, to be placed over the central area of the airport, was required to be installed without disrupting any passenger activity. Furthermore, the subject was fully prefabricated between the active runways of the airport over the past year.
Mammoet overcame this obstacle by disconnecting the roof panels into “roughly football field sized pieces” before transporting the segments to the new terminal expansion.
With the panels’ weight varying between 40 tonnes through to 632 tonnes and holding dimensions of 72 metres x 50 metres x 6 metres, Mammoet used four of its Mega Jack 800 towers in tandem with its SPMTs to lift and shift the roof.
To minimise disruption and keep safety at the forefront of its operations, Mammoet transported the panels at a speed of 1.6 kilometres per hour. Panels that needed to be installed over already populated areas was completed overnight during strict closures to ensure members of the public would not risk their personal safety.
Once the area was verified to be clear of all pedestrians, the installation of the roof panels could begin. Each panel was installed using stationary skidding propelled by strand jacks and lowered with the skidding jacks onto column isolators.
The next set of panels were then rolled into position down the bottom flanges of the previously set panels. The panels were safely secured with consideration for potential elevated wind and project specific seismic requirements before the public were allowed to reoccupy the area below.
A major complexity with the project was the material used by the designers of the roof. Using sustainably sourced and regionally produced wood and considering the load’s weight and its distribution across the towers, deflection became a very real possibility. Factoring this in, Mammoet kept a tight hold on any potential for deflection at every stage of any jacking up, lifting, transporting, and installation.
Mammoet has placed 16 of the 20 panels so far, with the rest of the work to be completed in 2024 after the interior of the new terminal has been built.
A video of the engineering feat can be seen here.