Civil Engineer, Prein & Newhof, Grand Rapids, MI
Project Manager and Director of Airport Services, Rust Environment & Infrastructure, Des Moines, IA
Pages: 10 Published: Jan 1998
In 1995, Kent County International Airport began building a new crosswind runway. The new runway traversed a 66-ft (20.1-m) deep ravine and a stream. Designers chose to enclose the stream in a 60-in (1500-mm) inside diameter reinforced concrete pipe before building the runway embankment. To minimize earth loads on the rigid concrete pipe, a narrow 10-ft (3-m) trench was specified. Safety authorities demanded a wider trench, however, in spite of vertical clay trench walls. Because a wider trench would place unacceptable earth loads on the pipe, designers proposed a modified narrow trench and backfilling the pipe with flowable fill. Flowable fill was placed to the springline; then granular soil was compacted to 12 in (30 cm) above the crown of the pipe before a clay embankment was placed over it to the final grade. The culvert pipe has been inspected three times since installation and is performing well.
flowable fill, trench safety, concrete pipe, rigid pipe, deep fills, pipe design, SAMM, PIPECAR, trench design, buoyancy, airports, drainage
Paper ID: STP13078S