Mining Publication: Evaluation of the Transverse Load Capacity of Block Stoppings for Mine Ventilation Control
The transverse loading requirement for stoppings as specified in the current Code of Federal Regulations is 39 pounds per square foot. This measure is based on physical testing of a freestanding wall in accordance with ASTM E 72 specifications, where the dominant parameter is the tensile strength of the sealant. A new protocol based on arching has been developed to determine the true transverse load capacity of stoppings. Arching is achieved by the restraint of the stopping against the mine roof and floor, whereby compressive forces are developed within the wall. A laboratory procedure using the NIOSH Mine Roof Simulator to simulate rigid arching of stoppings was developed and verified through full-scale in-mine tests. Using this protocol, a systematic study of the design parameters that affect arching capability in block stoppings was conducted. The study included a theoretical assessment of load capacity of various stopping constructions under various loading conditions. This approach should lead to a safer mine environment by matching the transverse load capabilities of the stopping design to the requirements in the mine to ensure proper ventilation control is maintained.