| Kitchell Contractors is building a 12-story, 1 million-square-foot tower for Phoenix Children's Hospital. Terry Ertter photo. |
The meltdown of America's financial markets this summer forced builders in Arizona to pull back from a number of planned projects, but several of the state's major health care projects continue moving forward. The Phoenix and Tucson areas have added several new hospitals in the past couple of years and expanded others. Rapidly growing small towns either have new facilities that are under construction or soon to begin construction.
Considering Arizona's reputation as a retirement destination, it's natural to assume the bulk of new medical construction would be for geriatric care. That's not the case, however, for three health care projects currently under way in the state. The focus at all three is squarely on children's care.
Why so many children's hospitals? Retirees are not the only people moving to Arizona. The state's employers need workers, and the workers coming into Arizona bring their families along. The demand for pediatric care has increased.
The largest of the three projects is an expansion of the Phoenix Children's Hospital in downtown Phoenix. Farther east, in Mesa, Banner Desert Hospital has a new seven-story tower going up, and that building will be dedicated entirely to children's care. Tucson has a new six-story addition to the University Medical Center well under way. The top three floors of that new building will be Diamond Children's Medical Center, Tucson's first children's hospital.
Phoenix-based Kitchell Contractors, a Kitchell Corp. company, is serving as the construction manager at-risk on all three projects. Hospital construction has been a Kitchell specialty for many years, and the experience has served the company well on the three sites, according to Kitchell.
Kitchell projects directors Jim Pullen, Russ Korcuska and Pat Watson all noted that the biggest challenge, by far, on each of their projects was the first phase, when they had to locate and modify existing underground utilities. The three projects all had extensive networks of utilities just beneath the surface of the building sites.
Phoenix Children's Hospital
The bright purple and red exteriors of the building at Phoenix Children's Hospital make it a high-profile facility in the Phoenix area. That profile will grow considerably as the new 12-story, 1-million-square-foot tower rises into the skyline during the coming months. The tower is the main element in an expansion and remodeling project that totals $420 million.
The entire project more than doubles the size of the campus. The expansion phase, targeted for completion in 2011, includes three new parking structures (1,750 cars) and a 30,000-square-foot central plant and loading dock.
“The central plant is a cast-in-place structure,” explained Kitchell project director Russ Korcuska. “The tower is structural steel with slab-on-metal decks and an exterior that will be about 45-percent masonry, 30-percent metal and 25-percent glass (curtain wall). The block is colorful, but not as bright as the current hospital exterior.
“The tower has one basement level about 20 feet deep. The foundation system includes drilled caisson piers. We began installing and relocating utilities in February (2008), and that phase took nearly six months and cost about $7 million. We relocated the main APS feed to the neighborhood as well as the Qwest and Cox feeds that ran down the middle of some of the purchased property.”
The relocation of utilities presented more challenges than a typical job. The area around PCH is an old neighborhood – at least by Phoenix standards – and it's a relatively high-density population area. There are a lot of old utilities underground, and they are not all documented.
“Anything you do in city streets and underground is very difficult,” Korcuska said. “Before digging, we did considerable investigation. We performed utility locating extensively with vacuum excavation and used BIM (Building Information Modeling) technology to create a 3-D model. The model gives us a clear picture of what we're dealing with and what kind of space we have for routing underground facilities.”
Kitchell has two full-time CAD technicians on site to enhance the 3-D plans provided by the architect. The enhanced models show details of walls and ceilings to make it easy to plan routes for mechanical systems. The software provides precise information to model ductwork and piping that's properly sized for available space. That information can go directly to the fabricators.
Perhaps the most unusual technical aspect of the project is the steel required to make the curved exterior design structurally sound. The designers wind-modeled the design to check stress loads and discovered that the curved outer wall made the building want to turn like a fan in the wind. The torque created stresses that required considerable bolstering of the building frame.
“We needed high-grade steel capable of carrying 600 pounds per foot,” Korcuska explained, “and we needed it in a specific shape and size. It turned out that Luxembourg was the only country with a mill that could cast that steel.”
Kitchell knew steel prices were likely to rise, so the company ordered the shapes and other steel from Luxembourg well in advance at a locked-in price. Steel prices did rise, and the advance purchase delivered significant savings to the customer.
“Schuff Steel helped with the engineer in the design process with steel connections to get the most cost-effective solution,” Korcuska noted. “University Mechanical (plumbing) and Delta Diversified (electrical) helped us do value design during the planning stage. They helped with determining things like pipe routing, selection of materials and prepurchasing equipment. We did prepurchase about $3 million of pipe.”
The same torque forces that required special steel from Luxembourg also drove the designers to specify brace-frame construction instead of moment-frame. The X pattern of brace-frame design is common on bridges and adds rigidity to the frame.
The new tower's scheduled completion is 2011. When complete, the new building will have several areas that duplicate functions in existing buildings. Those buildings will undergo extensive remodeling to serve new functions. The remodeling phase of the project will complete in 2012.
University Medical Center/Diamond Children's Medical Center
The centerpiece of the Tucson project is a six-story, $125-million tower adjacent to the existing eight-story main hospital building on the University of Arizona campus. The hospital serves double duty as both a patient-treatment facility and also the heart of Arizona's premier medical school. The top three floors of the tower will be dedicated to the Diamond Children's Medical Center.
Prior to the start of construction in July 2006, the site was occupied by a structure that housed three emergency generators. The roof of the structure was the hospital's heliport.
That building had to go before any construction could start, but you don't just cut off a hospital's emergency power – even for a couple of hours. Kitchell project director Pat Watson said the early construction phase was the part Kitchell was most concerned about going into the project.
“That was the highest risk phase, but it was all low-profile, below-grade work,” Watson said. “Except for the demo of the heliport, it wasn't visually interesting.
“Our first task was to determine where we were going to put the generators. We chose a site several hundred yards away from the existing building. It took 15 months to get the new generator building going, and we had to run new conduit from there to the existing hospital building. That was a quarter mile of open trench through existing utilities and facilities. We did a significant amount of utility locating. There's just no room for an incident when you're working around a hospital where all services are vital to patient care.”
A pair of rented 2,000-kilowatt temporary emergency generators provided emergency power while the permanent generators were being moved, reconnected and tested.
With the underground utilities and facilities finally out of the way, Kitchell was able to begin work on the foundation, which includes a partial basement that will bring mechanical and electrical connections from the basement of the existing building.
Watson credited early collaboration for eliminating $800,000 from the cost of construction early in the process.
“We paired up the structural engineer with the architect to examine possible savings. The IBC (International Building Code) is very strict for health care facilities, and many of the requirements relate to their site's seismic design category. If you don't do a site-specific survey, and you take the tables that they refer you to, most facilities in Arizona would require additional mechanical, plumbing and electrical distribution system seismic bracing.”
Other savings of time and money came from the use of a soil enhancement system. The structural engineers knew the existing soil could not adequately and cost effectively support the building.
“The popular option in the past,” according to Watson, “was to remove and replace soil. Figure about a month to export bad soil and import good soil. Here, we used an aggregate pier soil enhancement system. You drill a hole, fill it with aggregate and ram the aggregate to make it spread out to increase the bearing capacity of the soil around the hole.
“Kitchell used this technique previously on expansive clay soil at Mercy Gilbert Medical Center in Gilbert, Arizona,” Watson said. “UMC didn't have clay, but the process still worked.”
After the steel goes up and the concrete gets poured, Kitchell crews and subs will be working carefully to make sure all work contributes to the high level of air quality demanded by the hospital. That requires builders to pay close attention to what goes on inside walls and ceilings to control dust and moisture.
“We absolutely can't allow any mold or airborne contaminants,” Watson explained. “University Medical Center treats acutely ill patients, and many of them have compromised immune systems.”
Banner Desert Children's Hospital
| The fountain structure is a key element of the entrance area to the Banner hospital. Terry Ertter photo. |
The sprawling Banner Desert campus in West Mesa started work on its new children's hospital in March 2006, and the projected completion of the new facility is in 2009. The seven-story tower is the primary component in a $254-million expansion that includes a new 1,200-car parking structure and pedestrian sky bridge, a new shipping/loading facility and expansion of existing buildings.
Like the other two projects, the Mesa site involved a maze of underground utilities that had to be located and moved outside the footprint of the new tower. Additional power demands for the new building required a major upgrade of the electrical infrastructure with redundancies in both directions. SRP installed new switch cabinets on the west side of the canal that forms the western boundary of the campus.
“We had to come in under the canal to connect,” said Kitchell project director Jim Pullen.
Space had grown tight on the campus, so the preconstruction phase required considerable planning and collaboration. During that phase, Kitchell and the structural engineers examined a building well away from the tower site. Hospital plans called for a future addition of a third floor on that building, but the engineers determined the building could not support the addition.
| The second tower (short structure) at Banner Hospital is being built with future expansion in mind. Courtesy of Kitchell. |
“We found a new location that could support the expansion,” says Pullen, “and we could see that we needed to move that phase of the project up. There would be no construction access to the area once the new tower was built. We added a third floor to that building while we worked on footings for the new building.”
As was true in Tucson, a site-specific survey changed the site's seismic design category.
“The soil here is better than expected,” Pullen noted.
Pullen supplied construction details, saying, “The building is on caisson and grade beam foundations with moment-framed steel structure and concrete slab on deck design. The moment-frame design was chosen for flexibility in the future. It allows clear access at 30-foot nominal spacing between columns. Other steel design, such as braced-frame design, limits the usable space between the columns, as a diagonal steel brace is left between each column.
“The north two-story tower plans call for five more floors, with the steel columns protruding through the roof and capped to allow ease of expansion in the future. We also made accommodations with enlarged elevator shafts and pits to allow four additional elevators.”
The building includes some architectural precast concrete, but most of the concrete work is formed in place. The major exception is the large fountain at the entrance. Hospital administrators want the first impression to be as positive as possible for children and families, and the fountain plays a key role.
“It's the most unique concrete feature in the project,” Pullen observed.
The positive first impression is reinforced by a large atrium at the entrance. The atrium is indoors, but it will have an outdoor feeling to help ease the transition.
The hospital's interior design and decoration are all tied to the central theme of “Through the Eyes of a Child.”
“The idea,” Pullen said, “is to create a room that each child can see as his or her own place.” Each room will have its own unique look from outside.
The initial concept called for a built-out façade around the entrance to each room. That created issues with cleaning and maintenance, so the architect found a plastic laminate material less than half an inch thick that can accept a 3-D pattern to create the illusion of a built-out wall.
Pullen notes that “It's a solution that provides cost savings during construction, and it will be much easier to clean and maintain. Also, it will be easy to replace if the hospital decides to change themes in the future.”
The three new hospitals should have a tremendous positive impact on Arizona. They are the kind of first-rate facilities that improve the quality of life in the communities they serve.
|