Humidity: A Cyclic Effect in Coal Mine Roof Stability.
NTIS: PB 283 741 :19 pages
Climatic conditions were compared with roof fall occurrence from April 1, 1972, to December 31, 1975, by the Bureau of Mines. These comparisons indicated that humidity has a strong influence on roof fall occurrence rates. Cubic regression techniques were used to develop best fit curves. Statistical analysis of these curves indicated that both were sinusoidal and exhibited positive correlation with each other. The sine waves have a period of 1 year with maximum and minimum inflection points in August and February.
IH; Report of Investigation;
NTIS Accession No.
NTIS: PB 283 741