NIOSHTIC-2 Publications Search
NIOSH safety performance testing protocols for standing roof supports and longwall shields.
Proceedings: new technology for coal mine roof support. Mark C, Dolinar DR, Tuchman RJ, Barczak TM, Signer SP, Wopat PF, eds. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2000-151; (IC 9453), 2000 Oct; :207-221
The safety of mine workers depends on the proper installation of roof supports to prevent the ground from collapsing into the working areas of an underground mine. As new support systems are developed, they need to be properly evaluated to make sure that they are capable of providing adequate roof support before they are first used in a mine. In addition to making certain that the supports meet basic safety criteria, the limitations of the support need to be fully defined in order to avoid improper application of a particular support design. The National Institute for Occupational Safety and Health (NIOSH) operates a world-class facility called the Safety Structures Testing Laboratory. This laboratory contains a unique load frame, the Mine Roof Simulator, which is capable of stimulating the ground behavior in underground mines for conducting full-scale evaluations of roof support systems. Safety performance testing protocols using the unique Mine Roof Simulator have been developed for both standing roof support systems and longwall shield supports. The purpose of this paper is to describe these test procedures. The protocol for standing roof supports incorporates seven test series: (1)uniform loading baseline tests, (2)height evaluations, (3)asymmetric loading, (4)biaxial loading, (5)load rate studies, (6)active loading determination, and (7)static loading evaluations. For longwall shields, a four-series test program consists of (1)transfer of horizontal load to the caving shield-lemniscate assembly (zero friction test), (2)point loading of shield joints due to lateral movement or rotation of the canopy, (3)evaluation of leg socket and leg cylinder integrity, and (4)face-to-waste racking of the shield. In addition, an evaluation of the shield's hydraulic components will be conducted prior to the performance testing. These protocols will provide state-of-the-art safety performance evaluations of emerging support technologies, as well as a means to assess the safety of both new and aging longwall shields. Hence, this effort will enhance the safety of mine workers by ensuring that critical support elements are properly designed and that aging supports are retired before their support capability is jeopardized.
Coal-mining; Structural-analysis; Performance-capability; Accident-analysis; Accident-potential
Mark-C; Dolinar-DR; Tuchman-RJ; Barczak-TM; Signer-SP; Wopat-PF
Information Circular 9453 - Proceedings: New technology for Coal Mine Roof Support
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division