Schwing

New Stadium

New Stadium Races Toward Super Bowl 50
The race is on at the new Levi’s® Stadium under construction in Santa Clara, California. After breaking ground in April 2012, the new home of the San Francisco 49ers was awarded the Super Bowl for 2016 – the 50th anniversary of the NFL’s biggest game. While over four years may seem like sufficient time to build the $1.2 billion structure, the NFL mandates any stadium awarded a Super Bowl must have two years in operation before they host the biggest game in football. The Design/Build team of Turner Construction and Devcon Construction (Turner/Devcon, A Joint Venture), Santa Clara, chose ACPA member CONCO of Concord, California to help meet the ambitious schedule with their fleet of concrete pumps.

Because of the aggressive pace required to open in August 2014, the construction was divided into four separate projects – the two midfield sections and the two end zone sections – as opposed to the traditional method of building stadiums in a “wedding cake”, circling the stadium one section at a time. The four projects are being built simultaneously. But before the stadium could get off the ground, the foundation for all four segments had to be built. “We had to excavate 60,000 yards of dirt, reinforce and pump 18,000 cubic yards of concrete, backfill and build a half-mile of perimeter wall,” according to Dan Fink, CONCO project manager, “in 40 calendar days.”

“We basically worked day and night,” explained Vince Montelongo, CONCO’s project superintendent. “The crews would start at 5:00 a.m. and finish cleaning up at 1:00 a.m.” The project specifications made the level of difficulty extremely high for what is the largest structural steel building under construction in the United States. “Twenty-three semi truckloads of anchor bolts were needed for the foundation,” according to Fink, “and the tolerance was one-eighth of an inch.” Five survey crews were working at one time to assure correct placement of the bolts.

Concrete pumping was steady throughout the foundation’s construction. “The majority of the pumping was accomplished by our Schwing S 58 SX,” according to Gary Brandt, CONCO pump superintendent VP of marketing for the Bay Area. “We also used our Schwing KVM 52 and S 47 SX throughout the project.” The S 58 SX’s Overhead Roll and Fold boom with188-feet of reach provided the most coverage from a single set-up, but it was the ability to move to other locations quickly that was the most valuable. “There were no large slab pours for the foundation portion, just a lot of smaller pours. We typically pumped about 500 yards per day,” Fink noted, “Most of the concrete was a standard 4,000 psi mix, with 8,000 psi at shear lugs”

The S 58 SX utilizes Super X outriggers, which were particularly valuable on the crowded site. “With four projects going on at once, the site is a busy place,” said Brandt, “Pumping set-ups are both inside and outside the structure, so the narrow 29’ 2” front outrigger spread, and the ability to shoot the curved outriggers out and around other equipment and obstacles, are a big help.” The ability to provide smooth concrete output for the precision pours was aided by the Schwing 2525H-6 twin cylinder, all-hydraulic concrete pump with variable output to 213 cubic yards per hour at just 22 strokes per minute. “We also appreciate the fuel efficiency of the Schwing pumps,” Brandt noted.

“Everything from the equipment to the personnel on this job is the cream of the crop,” according to Fink, “We chose the people for their attitude and willingness to work long hours because failure was not an option.” Adding complexity to the production goals was the 12-hour limit in a work period that California requires on truck mixer drivers and pump operators for safety concerns. “Sometimes the truck mixer driver would time out on site and have to get a ride home with a replacement driver,” Fink said, “In the case of our operators, they would ‘hot seat’ with one pump operator finishing a pour and another operator would move the pump dirty and start another pour. Some days the pump ran continuously like this for nearly twenty four hours.” Pump maintenance is performed on site and, “there have been very few issues,” according to Brandt. “These pumps are real workhorses.”

With the short schedule to complete the foundation work and not a lot of preparation time, the CONCO crew met the deadline for Phase 1 in July 2012. “We worked as close to 24 hours per day as we could and nobody balked at it,” commented Fink. “I don’t think there was any other team that could have done a better job.” This sentiment was shared by Dave Masel, Turner/Devcon’s general superintendent. “They did an absolutely fantastic job considering the challenging schedule and simultaneously servicing four adjacent building sites.”

Since the successful completion of foundation work, CONCO crews have been working on concrete infill including slabs on metal deck, field retaining wall, and the cast-in-place steps used to reach the seating. Pre-cast sections make up the tiers supporting the 68,500 seats. In order to reach to the upper deck stairways, crews have placed as much as 300-feet of line connected to the fully extended boom of the S 58 SX. “The site is getting smaller and we have lost access to the in-field as the structure takes shape,” according to Montelongo, “So we lay down and anchor as much as two hundred feet of five-inch hard pipe and add one hundred feet of hose to reach the remote areas of the stands.” The concrete work is expected to be completed in October and will total approximately 60,000 cubic yards.

After crews finished the topping out of the structural steel of the structure in December 2012, it will take 18 months to add the electrical, mechanical and plumbing systems and pass inspections. Within the schedule to complete is the required two months needed to grow the natural grass playing field. Then there’s the “super flush.” Youth Groups, volunteers and workers will alternate flushing every toilet and urinal, and turning on every sink in the stadium for about a half-hour – meant to mimic halftime conditions – to see if the plumbing can handle it. “We’re working every inch, every day,” says Masel, who was in a similar role on the stadiums for the Kansas City Chiefs, Denver Broncos, and Philadelphia Eagles. “This is one of the fastest I have ever built, and I understand it is the 6th fastest ever.”

Dan Fink summed it up best, “It’s amazing what you can accomplish when no one cares who gets the credit.”