Building the Perfect Run

The concrete ski-jump was built on a 1.7H:1V slope, 160 feet long, and approximately 30 feet wide.

Utah Olympic Park utilizes geosynthetics to build a concrete ski jump.

Receiving calls to solve unique and challenging site problems is common for Presto Geosystems’ engineers and network representatives. In the Spring of 2017, Utah Olympic Park’s mountain manager contacted Presto for assistance with designing a new concrete ski jump for free-skiers and snowboarders to practice their jumps in the summer.

The site is an official United States Olympic Committee (USOC) training facility used by the Olympic Ski and Snowboard teams. Built for the Salt Lake 2002 Olympic Winter Games, this dynamic multi-use facility focuses on developing and growing winter sports in Utah and hosts ski jumping, Nordic combined, bobsled/luge, and skeleton events.

Presto’s 3D GEOWEB system was chosen as the concrete support system because of its ability to help resist settlement cracking. In other concrete applications, the system can outperform standard reinforced concrete and can reduce the normal 6-inch depth of reinforced concrete to 4 inches.

The concrete ski-jump was to be built on a 1.7H:1V slope, 160 feet long, and approximately 30 feet wide. With a 4-inch depth and a 150-pound-per-cubic-foot unit weight of the concrete, this meant that approximately 250,000 pounds of concrete had to be held in place on the slope. To accomplish this, a 6-inch-diameter pipe was buried 5 feet below grade at the crest, serving as a deadman anchor for heavy-duty tendons, secured to the pipe and to the GEOWEB panels.

“Ski tiles,” 4 inches by 36 inches, were attached to the concrete ramp with ramset anchors, overlapped from top to bottom, similar to shingles on a roof. An even surface from tile to tile is critical to give the athletes the perfect run on a snowboard or pair of skis to practice their skills. In order to achieve the required level surface, it was critical that the subgrade be graded precisely because any imperfections in the subgrade would be transferred to the surface of the concrete.

Presto’s experienced construction field representative was onsite for the GEOWEB installation and concrete infilling — and to ensure the subgrade was graded to precision standards.

Overcoming difficult site challenges takes careful planning, collaborative engineering, and construction experience. Geosynthetics can offer consultants innovative ways to solve complex site problems. Presto’s assistance — from preliminary design support through final construction — allowed for a successful completion of this challenging, high-profile project.

Information provided by Presto Geosystems (www.prestogeo.com).