Memphis, Tennessee -Memphis International Airport is a world-class facility serving more than 10 million passengers a year. It is the only airport in North America considered to be an “aerotropolis,” in which a city grows around the airport, connecting workers, suppliers, executives and goods to the global marketplace. FedEx Express (FedEx) was founded at Memphis International Airport in 1973 in order to help facilitate domestic and global trade and the company built a Super Hub sorting facility and administration building on the airfield.The FedEx Memphis World Hub has made the Memphis International Airport the second busiest cargo airport in the world, as it connects customers to more than 220 countries and territories on six continents. It encompasses a 500-acre area and includes parking slots for 175 aircraft and 42 miles of conveyor belts. With over 4,000 employees during the day and 8,000 at night, the facility keeps Memphis and FedEx connected to any point on the globe. The Memphis Hub supports the largest air cargo fleet in the world and handles about 3.3 million packages per day.
FedEx worked with Allen & Hoshall, Inc. on construction of a two-story canopy for international sorting operations and needed to find a drainage collection system to remove sheet flow from the construction area. Allen & Hoshall, Inc. has provided design and construction phase services for airside and landside projects at Memphis International Airport since 1960.
“The new canopy was to be constructed in a space between a nearly identical canopy and another FedEx operations building,” said James Simpson, Jr., PE, CPESC, Associate Principal with Allen & Hoshall, Inc. “We were to minimize impacts on ongoing FedEx operations in the vicinity. This dictated some elements of the design and construction, including the choice to install the drain product with minimal disturbance to the existing concrete.”
Slotted drain, a product manufactured from corrugated steel pipe, was selected for the solution. The slotted drain was fabricated by Contech Engineered Solutions, a member of the National Corrugated Steel Pipe Association (NCSPA). Using corrugated steel pipe cut along the longitudinal axis, a trapezoidal or straight-sided grate with reinforcing spacer plates is welded in place. This forms or creates a 1-3/4″ wide slot opening which collects runoff and channels it to the pipe below. Slotted drain was chosen because it provided a versatile and cost-effective surface water removal solution.
“Logistics and schedule sensitivity have been paramount requirements to achieve the success that FedEx expects and Frierson plans to deliver,” said Ben Eberle, Pre Construction Manager with T.W. Frierson Contractor, Inc. “The slotted drain [BMR1] water collector system had to be installed below the existing concrete pavement and required demolition to allow for the install.”
T.W. Frierson Contractor, Inc. installed 127 feet of 12-inch diameter 2-2/3 x 1/2, 188 feet of 15-inch diameter, 177 feet of 18-inch diameter and 238 feet of 24-inch diameter variable height, Aluminized [BMR2] slotted drain [BMR3] in approximately three weeks.[BMR4] In order to provide positive drainage flow in the pipe, variable height grate was used due to the level existing concrete surface. This is yet another benefit of the flexibility of corrugated steel pipe products.