GENERAL30442 - Laserfiche WebLink

Home Browse Search

JTM TRTUM 8 RSSOCIRTES TEL=~-995-7191 Rpr 13.~ 3=10 N0 .002 P..OS ~RiT11T 7-NEER ENB INEERINO TO 17119907193 P.00 Progress Report on Tatum House $ub4idence issues Page 4 Apri112,1l19b ' The war]usion that the over burden appeared to subside in a relatively coherent rockmeas is oonsistoat with ~ observations is the area, indudigg the effects of mining on Rancho Escondido and at Morley. Oolorado south of Trinidad. Thin would toad to contradict the conclusion that the intlnenoe of the aline would be drastic ea stated by OEMs or drastie sad dish~pp~tiive es stated by the State of Colorado, Department of Natural Resources, Divldon of MiaeraLr and Oeology6 .. Attwooll Bads that the hove damage id oonaisteat with subsidence lhilnrest . ~A The raw data for this study ie available is the Deaver O~ioe of the US Bureau of Mines in $ poorly orgaaized.8le. . fiDPB (6arllace DeLormatioa Predlollon $ysbem t.0) A compater program has been developed by the Department of Mining and Minerals Engineering, Virginia Polytechnic Institate and State University. This progi~am is used by the O8M in developing their subsidence models. The USBM has recently eognired this program for teetin8. ~ . I talked tq Dean Michael ISarnis, the FIead of the Department at VPI & $U, end one of the developers of the prograim. The eoaversadon centered around where the pra~ram had been used, how reliable it had been is duplicatillg case studies, sad whether it had been used in waters applications. He noted that they had had a good experience with the application, and that it had heart used in the west. He told me that empirical data could be inputted into the model, however it did not take into oonaideration the e~eete of water in the mine, and he world tend W intaease the eztraction to 90 96, in a room end pillar minim situation, to take this into account. i3e also advised me sot to confuse the "angle of draw" which tends to mardmize at 27°, and the "angle of influence° which can be much larger, 36° more or lees when measured the same way. He also gave me the name of the noftware distributor that handlea.the program. Subeequent>,y I obtained a copy of the program $rom Carlson Software. The program has eeverel diil'ereat methods that it uses to Predict surface detirrmatioa. A Pmiile ]?5tnctioa Method which utilizes data generated by many observations in the Eastern United States together with some site epeci$c parameters. It generates a subsidence curve that is along as azis that. is orthogonal to an infinitely long underground excavation. Aa Influence Fund~on 3aethod is an alteraetive. This method can calculate snbsidence curves using default data developed by oxperience in$astern Coalfields, or can allow the input of empirical data based on site epecdlic information. It will oalaulate subsidence in Dither transverse (orthogonal) or longitudinal directions. The OSM analysis did not use the right model, the Tatum HousQ ie situated longitudinally with respect to the underYround mining tit First North in the Golden Eagle mine.