By Brian Johnson
Dolan Media Newswires
Through the magic of computer imaging, the Vikings stadium project flashed before their eyes on a projector screen.
The images showed how the three-year project will progress, day-by-day, starting with the first hole in the ground east of the soon-to-be-demolished Metrodome, and traveling in a counterclockwise direction around the existing building’s footprint.
In the bottom right-hand corner of the screen, precise dates for each step of the project accompanied the images, moving along in a blur of motion.
“Hope we can build it this fast,” quipped Dave Mansell, general superintendent for Mortenson Construction, the project’s construction manager.
The virtual tour of the $975 million Vikings stadium project was part of an information session in Minneapolis, the first of four such events designed to explain the project, its timeline and work opportunities.
Speaking to about 380 people who squeezed into a room at the International Market Square building, Mortenson Construction officials vowed to expand the use of computer modeling for the project.
They also shed more light on the project’s schedule and bid opportunities for subcontractors and suppliers.
“I can promise you that the Mortenson/Thor team will do everything possible to make your experience on this project successful,” John Wood, Mortenson’s senior vice president, told the gathering.
One of the highlights was the demonstration of the virtual construction tool, known as “4D synchro modeling,” which considers the dimensions of length, width, depth and time.
Golden Valley-based Mortenson used the 4D model in its proposal to the Minnesota Sports Facilities Authority when it bid on the construction manager at risk contract. Some project details since have been modified, but the basic time line is unchanged.
With help from the virtual modeling, Mortenson will be able to “sit with all of our subcontractors and walk through the building” to “maximize our efficiencies out in the field,” Mansell said. “We are going to do some things … that some of you haven’t seen before.”
The 4D modeling is part of the Building Information Modeling phenomenon, known as BIM, which has been used for years to help construction project teams stay on schedule and improve quality.
Mortenson officials, however, say they will add some twists to the BIM concept for the 65,000-seat, 1.7-million-square-foot Vikings stadium.
“I think we like to take it to a little different place every project we do,” said Kevin Dalager, a Mortenson construction executive who worked on the TCF Bank Stadium and Union Depot projects.
Virtual design in construction often stops with the mechanical, electrical and plumbing components, he said.
For the Vikings stadium project, virtual design will go a few steps further. For example, it will include virtual window mockups where the ETFE roof system will meet the standard roof, Dalager said.
Steel components will be color-coded on the computer model to help the project team easily identify and understand the required steel finishes, such as primed, unprimed and fireproofed.
Virtual modeling was used for the TCF Bank Stadium and Target Field projects, but it has advanced since those projects were completed in 2009 and 2010, respectively. Dalager said it’s more common now for enclosure and interior subcontractor work.
“You didn’t typically see the enclosure or interior contractors doing it at all five years ago, where now it’s fairly common,” he said.
Mortenson expects to have more than 100 direct contractual relationships with subcontractors and suppliers for the Vikings project, not including many other “tier” subcontractors and suppliers.
Mortenson will award specific project components in four separate procurement packages.
Mortenson obtained proposals this month for the first and second bid packages. Bid package No. 1 includes long-span structural steel and the ETFE roof, and bid package No. 2 covers mechanical, electrical and plumbing work.
Those packages haven’t been awarded, but once they are there will be future meetings to address participation of minority- and women-owned businesses within those scopes of work, Dalager said.
The second and third bid packages will offer about 64 individual subcontract categories.
Mortenson will look for proposals in mid-September for package No. 3, which includes earthwork, stairs, foundation, railings, utilities, seating, stadia, technology, escalators, enclosure and elevators, among other tasks.
The construction management team plans a February 2014 timetable for the fourth package, which includes work such as interior and exterior finishes, masonry, carpentry, turf, landscaping/irrigation and signage.
Wood said the construction management team of Mortenson and Thor Construction will come up with a guaranteed maximum price for the project in mid-October and execute a contract to build at that guaranteed price around Nov. 1.
Construction will start “in earnest” in November, Wood said.
The project schedule has specific dates for key milestones, such as the demolition of the Metrodome (Jan. 20) and steel erection work (starting Aug. 7, 2014, and ending Oct. 31, 2015).
One of the project’s standout features is a transparent lid, known as an ETFE (ethylene tetrafluoroethylene) roof. Covering about half the building, it will be the largest clear ETFE roof in the world and the first on a stadium in the nation, according to the design team. Crews are expected to complete ETFE roof installation by Nov. 30, 2015.
“The significance of that is you have to put ETFE on when it’s warm out, 40 degrees or warmer, so we have to do that by the end of November 2015,” Mansell said.
The information sessions are designed to update specialty contractors and suppliers about the project schedule and work opportunities.
The Vikings stadium legislation and the project’s “equity plan” set participation goals of 11 percent women-owned businesses and 9 percent minority-owned businesses.
Alphonso Hodges, owner of Hodges Cleaning Co., came to the event equipped with a pocketful of business cards promoting his company, which provides construction cleanup and other services.
“What brought me here is networking and working toward maybe a joint venture … with some big company that would help a small company like mine grow,” he said after the event.
A minority and a military veteran, Hodges hasn’t received his disadvantaged business enterprise (DBE) certification. He started his company in 1993.
“I took a break for a couple of years and I am just starting back,” he explained.
On the workforce side, the goal is to set aside 32 percent of the construction work hours for minorities and 6 percent for women.
Lynn Littlejohn, Mortenson’s director of community affairs, said worker goals apply only to onsite construction trades.
“We are not talking about professional staff who may be assigned onsite in the trailer,” Littlejohn said. “It’s not your PM, not your sup, not your safety person. It’s your trade worker.”