A City Prepares for the Olympics
This massive 144-bridge project along Salt Lake City's Interstate I-15 highway saw the state's first use of coatings for concrete to fight the twin problems of salt and graffiti.
was built almost 30 years ago to carry a population of one million people. However, the city has doubled in size since that time, and the 2002 Olympics competition is expected to bring in at least a million tourists all by itself. Clearly, that growing traffic challenged the Utah Department of Transportation (UDOT) to find solutions to the city’s transportation problem. Coupled with that problem is the age of the current highway system, along with an annual freeze/thaw cycle and too many applications of the salt that gives the city its name.
UDOT’s answer: a new light rail line, expanded bus service and a major expansion of I-15, which runs north-south and bisects Salt Lake County. Interstate 15 will also feature the state’s first high occupancy vehicle lanes and an Intelligent Transportation System. Ultimately, the project will involve not just the new transportation system, but also a renovation of the entire downtown area, including new construction by the Mormon Church that is headquartered in Salt Lake City.
The new highway construction project is 16.5 miles long and includes 144 new bridges, which are higher, wider and longer than the ones severely damaged by salt and time that they replace. The new construction incorporates 55,000 tons of steel and 20 million square feet of concrete surface. The I-15 project also includes soundwall barriers and drought-resistant landscaping.
This massive project, which will cost $1.59 billion overall, was headed by general contractor Wasatch Constructors, a joint venture between Keiwit Construction, Granite Construction and Morrison-Knudsen. Said to be the biggest road construction project in the country, it is Utah’s first-ever design/build transportation project, in which design and construction are handled simultaneously.
The design/build system, made possible through a federal Special Experimental Program 14 designation and passage of special state legislation, allowed the roadway to be built in fewer than five years—instead of the 10 originally planned—so it could be ready in time for the Olympics. The I-15 project called for 400 engineers in a dozen firms and involved an estimated three-quarters of the bridge designers in the country. So many designers and builders were needed that a dedicated office building was specially redesigned for UDOT, Wasatch and the project development team.
UDOT was very concerned about the highway project’s long-term maintenance needs, as well as ultimate public approval of the finished appearance of the work. The state had never before specified a coating for concrete, but a call for a chemical stain was included in the final I-15 specification. The stain would be applied to the concrete portions of the highway’s new bridges, as well as to soundwalls and other concrete barriers.
Bruce Toews, Sherwin-Williams Industrial and Marine group sales manager, and Dee McNeill, Sherwin-Williams corrosion engineer, demonstrated to UDOT how the company’s H&C® Concrete Stain, combining silicone and acrylic, bonds to the concrete so the surface cannot peel, crack or chip. The coating, when used with HB-150, reduces water absorption by more than 85% and chloride ion intrusion by more than 92%, assuring longer lasting concrete.
McNeill also explained how adding color to the project would improve the roadway’s overall aesthetics and that the opaque silicone-acrylic formulation would hide graffiti and enhance the project’s design. Inventory could be held at the many Sherwin-Williams stores in the overall project area so any graffiti can be quickly covered with matching stain without leaving unsightly patches.
“I call this the Miracle Stain,” says Wasatch Constructor’s contract administrator Bill Saumier, who is also charged with being the company’s advocate for project aesthetics. “You can cover over any graffiti with just two coats without having to sandblast it off. You can apply up to 50 coats before you need to sandblast, up to 3 mil thickness.” And eliminating sandblasting saves time, labor and further damage to concrete surfaces, he adds.
“In fact,” says Saumier, “we have a potential change order now to put this H&C® Stain on the abutments and wing walls, in some shade of gray still being determined, to blend with the unstained bridges in the area. It allows the concrete to breathe, which lets moisture escape and prevents the retaining walls from deteriorating as quickly.” His opinion: all states should consider the product as an affordable graffiti-fighting measure, especially as design/build becomes more prevalent.
The concrete painting contractor was Scott Derr Painting of Webster, TX. For the concrete part of the work, says Scott Derr, Sherwin-Williams was chosen as the sole supplier to ensure overall consistency of appearance. To protect the bridges from salt damage, the concrete in splash zones was first prepped with the Sherwin-Williams HB 150, which Derr notes can go either over or under the color coat. Then, two coats of stain were applied to concrete areas such as retaining walls, barriers, slope paving, columns and exterior girders.
When it came to the steel portions of the bridges, the components were built by four steel fabrication firms - Utah Pacific Bridge in Salt Lake City, Fought Steel and USI Steel in Portland, OR, and Roscoe Bridge in Billings, MT. The steel was first blasted with steel grit to remove slag and allow for uniform surface adhesion, and then primer was applied. Later, in the field, the steel was spot blasted at bolts and welds by Interstate Coatings, Inc., of Seattle, then spot primed and pressure washed. Stripe coats along bolts and edges gave extra protection before the contractor applied a full intermediate coat of Sherwin-Williams Recoatable Epoxy, topped with a Corothane II Satin that was chosen for its durability. “We go to great lengths to ensure a good application,” said Interstate’s Herb Terrill. According to Terrill, his firm was insistent on this choice of topcoating, primarily because of Corothane’s performance characteristics. “The coating is resilient, giving it high strength, and it encapsulates the steel for better protection,” says Terrill.
Galvanized downspouts on the bridge’s new drainage system were to be coated with a DTM wash primer from Sherwin-William, followed by applications of the same Recoatable Epoxy and Corothane II used on the steel.
In the I-15 project, color selection was a priority. Chris Petracca, of Sherwin-Williams’ Color and Design Marketing Department, assisted the I-15 project members in choosing colors picked up from the natural terrain. “The area had a great palette to chose from,” says Petracca: the plum colors of the mountains, used on the steel and grayed to a subdued purple hue called Mountain Dusk. The concrete is a sage green called Desert Sage, with a darker variant of the green used to give the concrete another design element. “The colors blend the bridge infrastructure in with the surroundings and soften the sterility of the concrete and steel,” says Petracca.
Since this was new construction, she adds, Sherwin-Williams was able to use its photo imaging process to take the engineers’ drawings and apply the actual colors used so the project team could see precisely how the colors would look.
The bridge painting on I-15 is expected to be 20% accomplished by the end of 1999, and completed by summer of 2001. But the care taken in bridge design, product selection and application gives the new I-15 bridges a life expectancy to 2076. Once the construction barrels are put away, the citizens of Salt Lake City will find all the current inconveniences worth the wait as they drive over their beautiful new bridges, protected well into the future.