Decay in Mine Timbers–Part I: Sampling Procedures and Conditions and Descriptions of Samples

To aid in the prevention of mine accidents, timber framing must be regularly inspected for decay. It is necessary to first develop a means of assessing the condition of timbers and determining their strengths. From 18 coal mines in Pennsylvania, West Virginia, Illinois, Alabama, Utah, and Colorado 430 timbers were removed for sampling. Timbers were predominantly oaks and maples (PA and WV), oaks and sweetgum (IL), southern pines (PL), and lodgepole pine (CO and UT). They were generally round and nonpreservative treated, and still retained their bark or remnants of it. White rot predominated in hardwood timbers collected in Illinois, Alabama, and West Virginia. In the Pennsylvania mines a rather even distribution of white and brown rot was evidenced; many timbers contained mixtures of white and brown rot. In softwood timbers from all mines only brown rot was visible. Moisture conditions and, hence, decay frequency varied widely both between mines and within a given mine. Where intake and return air courses were sampled in a given mine, both humidity and temperature were highest in the return.

You must be logged in to download any documents. Please login (login accounts are free) or learn how to Become a Member