AUGUST 1999    CIVIL ENGINEERING  MAGAZINE

The Olympic Games leave everlasting impressions on the landscapes of host cities. Designers working on three very different venues under construction for the 2002 Winter Games in Salt Lake City are combining Olympic needs with public recreation.
--Brian Fortner

Relining a RelicDramatic changes occur when the Olympics come to town. For Salt Lake City, the host of the XIX Olympic Winter Games in 2002, the summer of 1999 is the season of construction. Some of the best people in the design and construction businesses have gathered in Utah to create master plans, develop facility designs, and manage construction under the purview of the permanent venue construction team assembled by the Salt Lake Organizing Committee (SLOC). After all, you only get one shot at the Olympics—whether you’re an athlete or an engineer.

Although some of the venues for the 2002 Olympics already exist, three sites in particular are either being built from scratch or will replace outdated or unusable facilities. The three venues couldn’t be more different. One involves converting pastureland into a world-class cross-country skiing and biathlon course. Another includes building two ski jumps that share a common landing area on the side of a mountain. The third will serve as an icon for the Olympics—a $23.2-million, 255,000 sq ft (23,690 m2) speed-skating facility covered by a cable-suspended roof, one of the first buildings in the American West to feature such a design.
 
The three permanent venues being constructed for the Olympics could become grand dramatic statements, but the SLOC wants to make simple statements, says Ranch Kimball, the SLOC’s director of permanent venue construction.
 
Several factors are driving Olympic facility design and construction in Salt Lake City: The venues must meet Olympic competition requirements and be suitable afterward to serve as world-class training facilities and provide public recreation. Athletic needs, aesthetic details, and environmental considerations are all woven into the design plans, says Grant Thomas, a vice president in the buildings and infrastructure group at Bechtel who took a leave of absence to become the SLOC’s senior vice president for venues.
 
The 250 acre (100 ha) Soldier Hollow cross-country skiing and biathlon course, which is being built in Wasatch Mountain State Park, is the most important venue simply because it will host the greatest number of Olympic events. “Most Olympic facilities in the world are either devoted to cross-country or biathlon—the dual approach is unique,” says Kevin Jardine, the SLOC project manager for Soldier Hollow. The agriculturally based Heber Valley, about 45 mi (72 km) from downtown Salt Lake City, will offer up 22 medal events over the course of 16 days at a converted sheep and cow pasture—a perfect setting. It’s perfect because the course requirements for Olympic competition are so rigid there are practically no other feasible sites available.
 
The venue must be located below 5,900 ft (1,800 m). It must also include specific slope gradients and precise lengths and categories of hills. Exact percentages must govern the relationships between flat, hilly, and undulating terrain, and the venue must meet requirements for the positions along the course where certain hills of certain grades and lengths should occur, says John Aalberg, the director of cross-country for the SLOC and a former Olympic athlete. “The project is a lot more complex than we originally thought,” Aalberg says. Instead of working with the terrain to determine the course, the designers are working with a list of requirements and trying to make the land conform to the list.
 

EDAW INC.
As Salt Lake City, top, prepares for the 2002 Olympics, construction begins on three sites that must serve as public facilities when the games are through. The cross-country and biathlon venue, left, covers 250 acres (100 ha) and is being constructed in Wasatch Mountain State Park. More than 14 mi (23 km) of trails will be built for 22 events. To reduce the footprint of the site, the trail system uses many crossovers and loops so races with different lengths can be run on the same course. 

On top of all the requirements, 18 course designs, ranging in length from 0.9 to 31 mi (1.5 to 50 km), needed to be configured on 14 mi (23 km) of constructed trails. Many loops and crossover trails have been designed into the maze to accommodate different distances. “It’s like a very complex jigsaw puzzle,” says Phil Hendricks, Jr., a senior associate at EDAW in Fort Collins, Colorado, which is providing land planning and design services for the project.
 
Construction of permanent facilities will cost about $9 million and will include four bid packages: trails, the site stadium area and utilities, an 8,000 sq ft (743 m2) competition management building, and a snowmaking system. Stable natural snowfall is questionable at this altitude in Utah, so a $1.5-million snowmaking system will be installed. The trails also are oriented to minimize snowmelt; wherever possible trail designers avoided south-facing pitches. To transport water to the site for snow, the SLOC agreed to contribute $1 million toward the construction of a $6-million pressurized irrigation system for local farmers. The SLOC will tap into that system and build a 2 million gal (7,570 m3) water storage pond for making snow.
 
Because not many contractors in the world have built ski trails, all of the contractors are being prequalified. The contracts are based on a guaranteed maximum price, and bonus clauses allow contractors to share a percentage of leftover funds once the project is completed. The trails contract has been awarded to W.W. Clyde & Company, of Springville, Utah.
 
International cross-country skiing competition requires a trail width of at least 16.4 ft (5 m). “It’s more like a road,” Aalberg says. Even so, the trails contractor has to understand that the trails are not roads and don’t necessarily have to be flat and straight. “If there’s a rock in the way, we would rather go around it than move it,” Aalberg says.

SWECO INTERNATIONAL

About 110,000 cu yd (84,128 m3) of earth will be moved, but course designers are still trying to follow the natural terrain, partly to minimize cut-and-fill requirements. Retaining walls will be required in about a dozen locations to stabilize slopes that have been disturbed, says Paul Taylor, a principal of Bingham Engineering in Salt Lake City, which is providing civil engineering design services at Soldier Hollow. Most of the grading is being done around the stadium area and the level shooting range for
the biathlon. Numerous culverts and drainage systems are being installed to keep water off the course.
 
The openness of the site makes it extremely spectator friendly. “It’s probably one of the best sites in the world,” Jardine says. Even so, television broadcasters, which are footing a large sum of the construction costs for rights to the games, have requested a tree-lined finish site, so more than 2,000 trees will be transplanted to the sagebrush-covered mountainside. Some will be used to shade the trails, which will help keep the snow from melting. A pedestrian bridge over the competition area will enable spectators to enter the stadium area during races. The SLOC expects construction to be completed by November 2000.
 
Just up the road from Soldier Hollow but at a significantly higher elevation is the Utah Winter Sports Park, in Park City. The bobsled and luge facilities were built in 1995, but construction of world-class ski jumps, which will cost in excess of $10 million, continues. The Olympic ski jumps for the XIX Games will include two sizes: the K-120 and the K-90. These roughly relate to the maximum distance, in meters, that the jumpers fly. The critical point K is the point at which the landing hill begins to curve away from the downward slope (see figure).
 
Although the Winter Sports Park originally had a K-90 jump, it did not meet Olympic standards and had to be removed. “If we built the one hundred and twenty meter jump near the existing ninety meter takeoff point, jumpers would be more exposed to crosswinds from the ridgeline,” adds Peter Emerson, the executive officer of operations for Edwards & Daniels Architects in Salt Lake City. The designers reconfigured the jumps by moving them 23 ft (7 m) into the mountainside to maintain the ridgeline, which will now act as a wind buffer. “It’s like putting in a runway—you don’t want crosswinds,” says Arnie Nishioka, the project’s civil engineer of record, who works for Holmes & Narver in Salt Lake City.
 
By configuring the parallel ski jumps into the existing hill, the venue should blend in better with the natural landscape. A 150 ft (46 m) tall ski jump tower, a height common in Europe, could have become an obtrusive landmark, says Marty Volla, the SLOC’s ski jump project manager. Instead, he says they “sort of carved [the jumps] into the hill.” Also, jumps that are close together can share a common outrun, minimizing on-hill construction.
 
Excavation material, more than 440,000 cu yd (12,460 m3) of it, was used to extend and counterslope the outrun area for the jumpers and provide a foundation for temporary bleachers that will seat about 20,000 spectators during the Olympics. The material was compacted to a relative density of about 90 percent. Between 80,000 and 100,000 cu yd (61,184 and 76,480 m3) of rock had to be blasted from the site, Nishioka says.
 
Aside from the steep slope, the project presents a geometric challenge involving compound radii. The critical points relate to established formulas for ski jumps used for international competition. The angle and placement of the hill in relation to wind currents, as well as the profile of the hill between takeoff and landing, are left up to the designer. Computer programs were used to determine the best alignments and hill placements. The jumps will be no higher than 10 ft (3 m) from the ground and jumpers will be no more than 15 to 20 ft (4.6 to 6 m) above the surface during their flights. The profile of the ski jump and landing hill basically follows the flight of the jumper.
 

JACOBSEN CONSTRUCTION
More than 440,000 cu yd (12,460 m3) of material has been excavated from the ski jump. Most of it is being used for fill around the outrun area, where temporary spectator seating will be built. 

“The challenge is to understand ski jumps—it’s new to all of us,” says Volla. To learn more about ski jump design, the SLOC brought international expertise on board, including renowned ski jump designer Kurt-Evan Sonehag of SWECO International in Falun, Sweden. The design team also made a trip to several world-class ski jumping facilities in Europe and Japan.
 
All the jumps around the world have drainage problems, Emerson says. Because natural springs would dump water onto the landing hill and outrun at the Winter Sports Park, 12 in. (300 mm) perforated pipe is being used to divert the runoff. Also, a gravel base beneath the concrete landing hill will act as a capillary water barrier, and a trench drain at the end of the concrete outrun will collect sheeting water.
 
Because the jumping facility is located on a 35 degree slope, the question of constructibility arose. The number one concern is keeping the jump and landing hill from sliding down the mountain, says Greg Brickey, a principal of Brickey Design Associates in Scottsdale, Arizona, and the structural engineer of record for the project. Both jumps are similar in design and share a common U point, which is where the landing hills end and the common outrun begins. The K-120 is higher and located farther up the mountainside than the K-90 jump.
 
Tensioned rock anchors 15 to 25 ft (4.6 to 7.6 m) long driven into bedrock hold 7 ft (2.1 m) high and 16 ft (4.9 m) long concrete piers in place. The large jump has 11 piers and the smaller, 9. The piers are covered with about 4.5 ft (1.4 m) of backfill, which leaves about 2.5 ft (0.8 m) of pier above the surface. Steel bents on top of the piers support steel girders that run the length of the jump and connect the piers. A 3 in. (76 mm) metal deck and 8 in. (200 mm) of reinforced concrete form the ski jump surface. Guide boards similar to curbs will create a trough for about 18 in. (457 mm) of snow.
 
Because the facility will be used for summer jumping, a slick plastic jumping surface will be installed on the concrete. A snow net must then be placed on the jump and landing hill in winter to keep snow from sliding off the hill. The snow net helps create friction between the snow and the surface of the jumps and landing hills. A major problem with the steep slopes for ski jumping is what’s known as losing the hill.
 
Six inch (150 mm) reinforced slabs on grade will make up the landing hills. To keep the landing hills in place, Jacobsen Construction Company, of Salt Lake City, is installing grade beams that are tied into bedrock. The beams are placed 30 ft (9 m) on center across the landing hill. A special mix of concrete—a little drier than usual—will be pumped on-site and screeded quickly with special equipment to keep it from sliding down the mountain. A large tower crane installed about midway up the hill and two crawler cranes—one on top and one at the bottom—are moving all of the materials into place. In all, about 370 tons (336 Mg) of steel and 5,400 cu yd (4,130 m3) of concrete will be used.
 
Although the site is located in Park City, which typically gets a lot of snow, the SLOC is putting in a snowmaking system just in case. “We don’t know what God is going to provide us with in 2002 so we have to have snow making,” Volla says. The SLOC is aiming for a fall 2000 finish date.
 
Viewed from the top of the K-120 jump, the ski jumpers will appear to fly into the valley. It’s 430 ft (131 m) from the start house to the outrun, which is higher than any office building in Salt Lake City.
 
Meanwhile, on the city’s west side, the SLOC is designing the Oquirrh Park Speed Skating Oval, which it hopes will house the fastest ice in the world. The facility will be covered with a cable-suspended roof, which will reduce the inside volume of the building and, consequently, the heating and cooling costs. The structural design of the building is a collaboration between Ove Arup and Partners, of New York City, which is responsible for the arena portion, and Martin/Martin-Utah, of Salt Lake City, which is designing other parts of the building. The architect is Gillies Stransky Brems Smith, of Salt Lake City. Because the temperature, both of the ice and of the air inside the building, is extremely important during athletic competitions, the SLOC decided that the smaller the building envelope, the easier it would be to maintain consistent temperatures.
 

The cable suspended 
roof has less than half 
the amount of steel that 
would have been used 
on a steel truss system. 
Less steel means less 
weight, which makes
the roof susceptible 
to wind loads.
The girders for the cable-suspended roof will be 36 in. (914 mm) deep wide-flanged curved steel beams located inside the building. Angled cable hangers will connect each girder at nine points to the main suspension cable. The angled cables decrease the load on the girders by as much as 60 percent compared with vertical hangers, says Ignacio Barandiaran, an associate with Ove Arup. Although special detailing will be needed for the joints and connections, the cost of the suspended roof is still less than that of a truss or arch system, and these would have increased the roof height by at least 20 ft (6 m), Barandiaran says. The total span is 310 ft (94 m). The main suspension cables, which are 3.5 in. (90 mm) in diameter, are attached to 109 ft (33 m) tall masts—12 pairs in all. The total length of the building is 650 ft (198 m).
 
Each mast consists of two steel columns and is 10 ft (3 m) wide at its base. Concrete spread footings—10 ft (3 m) wide, 22 ft (6.7 m) long, and 2 ft (0.6 m) thick—will be buried 10 ft (3 m) to help anchor the masts. The masts will include 65 ft (20 m) long booms, each anchored by a cable leading to a pile cap on top of five 75 ft (23 m) long driven H piles. Diagonal cables will lead from the pile caps to the intersection of the boom and the mast on the west side of the building, and 3 by 3 ft (0.9 by 0.9 m) concrete grade beams will connect the pile caps to the spread footings.
 
The cables can only resist tension, so pipe bracing between the pile caps and the masts will be used on the east side of the building to resist lateral loads in two directions. Because the design team was focused on the most economical design, it’s ironic that it had to consider wind suction, Barandiaran says. The cable-suspended roof has less than half the amount of steel that would have been used on a steel truss system. Less steel means less weight, which makes the roof susceptible to wind loads.
 
Inside the building, the 7 in. (178 mm) thick primary concrete slab for the ice surface will be extremely flat and smooth—there will be no joints. The tolerance is only 0.25 in. (6.4 mm) for the entire 1,312 ft (400 m) long oval. Many of the design decisions revolve around making fast ice, says Charles Sandvig, the SLOC’s project manager.
 
Two crews will start an 1,100 cu yd (841 m3) continuous pour in the same place and work in opposite directions. The reinforced concrete slab will include 1.25 in. (32 mm) diameter cooling tubes that are 4 in. (100 mm) on center. To keep the ground from freezing beneath the racing surface and possibly exposing it to heave, the designers have included two layers of rigid insulation beneath the cold slab and added heating tubes embedded in a 6 in. (152 mm) layer of sand and pea gravel. Each layer of insulation will be 1.5 in. (38 mm) thick. The heating tubes are 12 in. (305 mm) on center. Compacted granular fill 6 in. (152 mm) deep will provide the base.
 

The cable-suspended roof for the Oquirrh Park Speed Skating Oval consists of a 310 ft (94 m) span supported by 12 pairs of 109 ft (33 m) tall masts, a 3.5 in. (90 mm) diameter main cable, and angled hangers connected to a 36 in. (914 mm) deep steel girder inside the building. 
 
Racers and other event participants, such as judges and trainers, won’t even walk across the ice. A cast-in-place concrete tunnel 12 to 40 ft (3.7 to 12 m) wide will traverse the facility beneath the racing surface, and a stairway from the tunnel to the middle of the oval will provide access to the racing surface. The 40 ft (12 m) wide section that will house changing areas is near the three-story administration building (one story below grade) and the main entrance to the facility.
 
To decrease the risk of settling after backfilling the tunnel, the designers have placed 40 ft (12 m) long tapered concrete wings on the tunnel lid where it crosses the oval’s racing lanes. The concrete wings, which are 12 to 15 ft (3.7 to 4.6 ft) wide and taper in thickness from 1 ft to 8 in. (0.3 m to 200 mm), will rest on native soil to decrease the possibility of settling, says Steven Judd, a principal with Martin/Martin-Utah.
 
Two 100 by 200 ft (30 by 60 m) hockey rinks in the middle of the racing oval will be built for use after the Olympic Games. In addition, a massive tent city complete with spectator queuing areas, athlete arrival terminals, and temporary competition buildings will rise next to the building. During the Olympics spectators won’t see the two-story glass atrium that will serve as the permanent entrance to the facility after the Games. As a crowd control measure, Olympic athletes will use that entrance, and spectators will enter through the back of the facility.
 
All three permanent venues under construction for the Olympics could have been designed only for Olympic competition. The passion of the athletes, as well as the high profile of the facilities, creates an atmosphere susceptible to grand schemes and designs. But the SLOC is staying true to its mission of leaving an Olympic legacy by designing and constructing facilities that can be used by both world-class athletes and the public long after the 2002 Winter Games are history.


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