2018 IDEAS2 Awards Brochure - 52

How's this for an construction challenge: Erect a 14-acre structural steel shade canopy weighing more than 17,000 tons over an
existing NFL stadium.
Thanks to Ruby+Associates, which provided full erection engineering services to fabricator/erector Hillsdale Fabricator, the
challenge was successfully completed.
Designed by architect HOK and structural engineer Thornton Tomasetti, the canopy was part of a $500 million renovation
of the 65,000-seat Hard Rock Stadium in Miami, home of the Miami Dolphins, Miami Hurricanes and Orange Bowl. The canopy
is supported by a total of eight super-columns. Transfer trusses
spanning between pairs of these columns support a 350-ft-tall
spire near each corner of the structure, and 64 structural cables,
up to 5 in. in diameter and up to 300 ft long, extend from the top
of the masts to suspend portions of the canopy. Ruby provided
comprehensive erection engineering, including demolition procedures for existing scoreboards; steel erection plans; structural
cable tensioning and installation plans; crane placement, clearance
and capacity studies; design of temporary falsework; design of specialty erection aids; development of rigging arrangements; and an
emergency hurricane bracing plan.
One of the primary objectives of Hillsdale's erection approach was minimizing the impact of the canopy installation on
the existing stadium. Typically, a structure of this magnitude requires a great deal of shoring for temporary support during construction. The bid documents suggested an erection procedure
using 24 shoring towers. Not only would this shoring have been
expensive and time-intensive to install, but it also would have
required extensive repairs to the stadium after removal.
Instead, Ruby developed an innovative steel erection plan
requiring minimal shoring and no alterations to the existing stadium. A temporary falsework system was shoehorned into each
corner of the stadium. The falsework system allowed for the installation of the lower mast section and cross transfer truss. After
these members were installed, the falsework was removed.
An aspect of the erection scheme borrowed from bridge
construction was the use of balanced cantilevers. By sequencing
construction such that loads imposed on the canopy structure
stayed in balance, each corner of the structure could be erected
in its entirety. Temporary tendons provided support until the
mast and permanent structural cables were in place. Once the
four corners of the canopy were erected, work progressed to the
installation of the upper mast and structural cables, the end zone
framing and finally the sideline framing. Another method used
to limit shoring and speed construction was the subassembly of
52

Ruby+Associates

2018 IDEAS2 Awards Brochure

Table of Contents for the Digital Edition of 2018 IDEAS2 Awards Brochure