Stacking Tubes or stand pipes are used to make large piles of material.
 
These Tubes support delivery conveyor systems. Most generally are  located in mines or terminal facilities where large piles can be placed.
 
Stacking Tubes  by Mast-Lepley Storage Structures are reinforced concrete and are available in 16', 18', 20', 24', 26', 30', Diameters with hts. At any 4' interval.
 
Silos, stacking tubes or stand pipes are all designed for the  material being stored. These designs range from many  wall openings, to large drive thru openings, to opening at grade for unloading with machinery.
 
Tops of each can be all open, partially open , to a solid roof with only one opening for material.
 
Wall openings range for  2' x 2' to 6' x 6' at specific locations designed by the engineer and customer.
 
Material being stacked piled generally is coal with other material, as sand , gravel, limestone etc.
 
Futures uses may be recycled concrete and asphalt.