At Denver International Airport, building has begun on two temporary shoring towers that will support the airport's iconic fabric tent roof during construction at the south end of the terminal. The current roof anchors are obstructing excavation for the $500-million South Terminal Redevelopment Program (STRP), which includes a 500-room Westin hotel, a public plaza and a new transit station.
On June 12, crews from Mortenson Hunt Saunders Triventure, the project's contractor, began drilling caissons for the steel support towers, which will stretch 30 ft below grade and 70 ft above ground and replace the eight roof anchors during the nearly four-year STRP job. The towers, which will take about five weeks to complete, will assume both vertical and horizontal roof loads from the anchors so that the anchors can be removed.
"The tricky part will be when we use the jacking system to transfer the load to the towers," says Steve Culbertson, senior project manager for Triventure. Transferring the entire 215,000-lb load from the mast will take about two weeks, he says, because each step has to be verified by the engineers.
"There's no guesswork in any of this," says Jorge Estevez, working for the Parsons project design management team. "The art is in analyzing the complex geometry of the fabric roof and anticipating how it will behave when the loads are transferred."
Crews from Mortenson Hunt Saunders Triventure, the project's contractor, began drilling caissons June 12.