Strata 15 PSI Block Stopping

The Strata 15 PSI Block Stopping provides another option in refuge alternatives. Developed for construction of safe rooms underground, the Strata 15 PSI stopping incorporates an explosion resistant steel access door.
Illustration of a 15 PSI Block Stopping
 
Constructing the Block Stopping

The stoppings consist of two concrete block walls built across the mine entry. Organosol 550 DT is used as an adhesive to adhere the concrete blocks together. Packsetter Grout bags frame the side and top edges, pre-loading the walls and sealing the edges. 

A steel access door is placed at least 12 inches from the floor and sealed into the wall. The interface between the door frame and the stopping is completely sealed with Organosol.

Once built to full height, the Packsetter bags are filled with Packsetter grout or other suitable material, where they conform to the roof and ribs to create an airtight seal that withstands overpressure.

The complete stopping cures to full strength in 3 days. Gunite or shotcrete may be spray applied on the surface of the outby side to eliminate the possibility of air leakage. Heights up to, and including, 8 feet have a set width of 15.25 inches. Heights greater than 8 feet, up to and including 11.5 feet, have a width of 22.875 inches.