Locally owned and operated, the Mobile Regional Airport
is located in southern Alabama and boasts over ten years of operations. It is the second airport in the country to have a federalized screening workforce. The airport is also home to the U.S. Coast Guard Aviation Training Center where advanced training is provided to U.S. Coast Guard pilots and aircrew.
In February 2013, the Mobile Airport Authority filed an application with the Federal Aviation Administration to garner a small stipend intended for continued development and rehabilitation for the airport. Part of that involved the rehabilitation of a single 1,740’ long, 132” diameter culvert that ran under Runway 14/32.
Given the location, replacement was completely out of the question. The Airport did not want to have to shut down operations while construction was underway.
Ultimately, they turned to a 120” diameter DuroMaxx® steel reinforced polyethylene (SRPE) liner pipe supplied by Contech Engineered Solutions to slipline into the existing culvert.
There were several things that had to be considered during the structural and hydraulic design. One of the most important considerations was the varying heights of cover (some areas carrying almost 35 feet of cover). The design also incorporated an existing junction box with a grade change of 0.2% to 1.04%. The entire installed length was 1,740 linear feet – the reline segments totaled 1,500 linear feet while an additional 240 linear feet were direct buried.
Owner of Indiana Reline, Inc., Chris Wisehart stated, "Our company has installed a wide variety of both small and large diameter liner pipe products over the years. This was our first time installing DuroMaxx steel reinforced polyethylene pipe for large diameter pipeline rehabilitation and we were pleased with the pipe’s performance and ease of handling. DuroMaxx was strong enough to maintain its shape against flotation forces, while also providing necessary buckling resistance to the grouting operation. The special 40 foot lengths reduced the number of pieces we had to handle and minimized the amount of joint welding we had to perform. We will gladly use DuroMaxx again."