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Issue link: http://airportbusiness.epubxp.com/i/813534
PROJECT MANAGEMENT April 2017 airportbusiness 29 the rugged Alaskan Gulf Coast between Sitka and Cordova. Bounded by the Gulf of Alaska on the South, nearly impenetrable mountains to the North and coastal glaciers to the East and West, Yakutat is about as remote as one can get in Alaska. There are no roads leading into or out of Yakutat. All commerce and access must occur via air or sea." For Knik Construction, that chamber of commerce description is more alluring than what is found in a travel brochure for the Bahamas. The adrenaline-pumping project that took them to this picturesque village is the Alaska Department of Transportation and Public Funding (ADOT&PF;) Yakutat Airport Runway Pavement Rehabilitation project. In Alaska, the state DOT maintains all the airports. The Yakutat Airport (YAK) is a state owned, public use airport located three nautical miles (6 km) southeast of the central business district of Yakutat. For the approximately 600 residents of Yakutat, this two runway airport is critical. On average, the FAA shows approximately 11,000 YAK airplane boardings annually. "Our project was the asphalt resurfacing of Runway 11/29, which is 8,136 feet by 194 feet (2,480 x 59 m), plus a 300 foot taxiway," said Amanda Gilliland, P.E., project manager with Knik Construction. "For the project, the runway was divided into three sections—raising the 29 end, which tapered from the existing runway to an elevated 2½ feet, a middle section where the runways intersect, that required varied profile milling, and a final section that needed ½-inch surface milling, which was enough to remove the texture grooves." The four-month project was a logistical challenge. All the heavy equipment, asphalt plant, supplies and asphalt concrete material had to be shipped via barge, which came to Yakutat once a month. More than 3,000 tons of asphalt concrete material was shipped to Yakutat with each cube of asphalt cement weighing about 27 tons. Knik started processing aggregate in March 2016 and began work on the runway on May 1, and it was opened up for use at the end of August. "We needed to carefully plan our shipments, because if anything was forgotten, we were stuck until the next month's barge, or we would need to fly it in," Gilliland stated. "It also meant that we needed very reliable equipment with maintenance up to date--we wouldn't want to send a truck over on the barge that needs new tires in a week." Knik had a three-worker milling crew. They used a Roadtec RX900e with 12.5-foot cutting drum. The machine features a Tier 4i Caterpillar C27 950 hp (700 kW) @ 1,800 rpm engine and 14-inch maximum cutting depth. A total of 6,000 tons of millings were removed, which was mixed with 50 percent D-1 local- ly-produced aggregate base and reused as fill on the section of the runway that required ele- vation to alleviate water issues. "Working in a remote location, it is bene- ficial to try to reuse immediately rather than stockpile, since the pile could sit for years or longer before it would be used as fill or RAP," said Gilliland. "To ensure accurate milling depth, our cold planer is equipped with GPS machine control." For the Yakutat Airport runway, Knik shipped over to the remote location a 400 TPH portable double drum Astec asphalt plant, eight belly-dump haul trucks, two 8-ton Blaw- Knox PF4410 tracked pavers, and two Roadtec SB-2500e Shuttle Buggy material transfer vehi- cles were paired up with the pavers. There were two paving crews with six workers on each, plus eight locally-hired truck drivers. For the most part, the existing runway served as the base for the paving. The asphalt plant was located near the shipping docks. The haul trucks would collect loads and transport them eight miles to the material transfer vehi- cles (MTVs) at the runway site. "Shuttle Buggies worked great – we rarely do any paving without them," Gilliland stated. "They give us consistency of HMA temperature and ensure against segregation…we've been using them a long time and, quite honestly, couldn't imagine doing any large paving proj- ects without them." According to Gilliland, the two MTVs kept both pavers productive and in instances where there was not adequate space for the trucks to dump, the belly dump could offload in anoth- er area not far from the paving train and the Shuttle Buggy would pick up the pile from there and transport it back to the paver – without having to stop the paver. The Shuttle Buggy has 25 tons (22.7 mt) storage capacity. The Yakutat Airport project required 62,000 tons of HMA making it the biggest paving proj- ect in Alaska for 2016. On a good production day, Knik Construction paved as much as 6,000