Randolph Mine Decline Rehabilitation
Kansas City, Missouri
Martin Marietta Materials
Atkinson will install 950 structural steel arch supports in two existing openings leading into the limestone mine, which must remain fully operational during construction. The steel supports will be placed every four feet along a declining 17-percent sloping grade. Atkinson also will install substantial steel and concrete structures at the intersections of 10 cross passages between the two access excavations. Approximately 17,500 cubic yards of concrete and cementitious backfill will be placed behind the steel supports and against the in-place ground to provide continuous support of the lose ground above.
Atkinson's scope of work also includes removing and reinstalling high-voltage power lines, as well as a water piping system to supply and discharge water during mining operations. A 4,000 linear-foot, 60-inch mainline conveyor belt used to transport crushed limestone out of the mine also will be removed and reinstalled for the purpose of increasing the efficiency of the conveyor system.
Construction is underway and substantial completion is scheduled for June 2016.