Photo courtesy McCarthy Building Cos.

“We started partnering early, and we truly became one team, and we had a model of one team, one office—and sometimes it was very difficult to know who it was without seeing them with the hardhat on” to see their company logo, says Tony Santana, deputy chief of design and construction for Valley Metro.

In addition to the new 1.6-mile track alignment, the $274-million project included the construction of two additional at-grade stations, the system’s first elevated station and a 90,830-sq-ft parking garage with 252 park-and-ride spaces. A new rail-only bridge spans Interstate 17, connecting the city’s downtown and east side to the West Valley, opening access to North Phoenix, the Sky Harbor Airport and Arizona State University (ASU) via a bus transit center built underneath the elevated rail.

Photo courtesy McCarthy Building Cos.

The university was a partner on one of the major concepts to come out of value engineering: a steel fiber-reinforced concrete mix that made it possible to eliminate traditional rebar when placing concrete on the embedded guideway, direct fixation track and bridge elements. The mix reduced the track slab thickness to 12 in. from 14 in.

It was the first use of fiber-reinforced concrete in this type of application in the country, according to the team. The material had added benefits: halving track construction to 121 days and improving sustainability.

“Fiber-reinforced concrete was a definite game-changer,” says Andrew Haines, vice president and manager of projects for Jacobs. “The challenge was that it had not really been done previously, so there was risk for the design team, the contractor, agency and the city.”

Photo courtesy McCarthy Building Cos.

ASU professor Barzin Mobasher and students from the School of Sustainable Engineering and the Built Environment validated the concrete, which showed “that using steel fibers with a dosage of 60 lb per cu yard significantly improved ductility and met the 45-year service life of 2 million fatigue cycles,” wrote Mobasher in an ASCE publication.

The materials made for a more “straightforward and efficient” process, where “fibers are batched and directly added to the concrete mixer at the plant [and then] poured into the formwork, which requires minimal setup,” he added. The team has gone on to present their solution to other universities and interested parties.

Complementary skillsets, such as McCarthy’s vertical expertise and Kiewit’s civil acumen, as well as generous resource sharing, allowed the joint venture to self-perform many elements, including underground utility relocation, earthwork, the bridge overpass, track installation and Metro Center Station concrete. “Our teams were intentionally mixed up throughout the project rather than dividing the work by company,” says Chris Jacobson, senior vice president operations for McCarthy.

Team integration happened at multiple levels, from executive to project manager, superintendent and builder, in what was called “field partnering,” says Santana. Field meetings, which also included utilities, would occur before each phase, where points of contact for stakeholders and conflicts that could occur were determined, part of the team’s “plan, don’t panic” mantra to avoid fights and establish a process for decision-making in the field.

A $1.4-million art budget was split among national and local artists. Community-reviewed installations reflect local points of interest including UFOs and a beloved dog park. Creative placements included an artist-designed foundation liner and works on a bridge ramp and escalator.
Photo courtesy McCarthy Building Cos.

Safety culture was another focal point for knowledge sharing, with contractors comparing plans point by point, pulling out the most robust to create a bespoke plan, while encouraging ideas from everyone on identifying, preventing and mitigating hazards.

The installation and relocation of 21,000 linear ft of utilities, including a 48-ft water main, constituted one of the riskiest parts of the project. The team added underground utility location software PointMan for field teams to easily “navigate what is in the area that is of potential risk,” says Jacobson. Real-time data was combined with a model created from as-builts and “pothole activity” to provide a comprehensive picture.

Preventing heat-related incidents while working in one of the hottest U.S. cities was crucial. The measures, including ice-chest equipped cooling stations, ensuring hydration breaks at prescribed intervals and heat education, were applied year-round to habitualize safe working behaviors.

Calling it the “best project, and best project team” on which he has participated, Haines noted that after “nearly 6 years of design and construction, almost 90% of the team was still intact.”