831168 Subsidence monitoring over western coal mines

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realized when field measurements, an additional aspect of the study concurrent with analytical investigations, indicating the relationship between increasing rock strain and increasing permeability are incorporated into hydraulic material descriptions. Hydrologic and structural calculations are presented to demonstrate computatiomal capabilities applicable to mine subsidence. Auth.

831162 SD~RFACE SUBSIDENCES, SURFACE S

~ DAMAGES AND SUBSIDENCE PREDICTIONS AND MODELING IN THE NORTHERN APPALACHIAN COALFIELD Peng, S S; Chymn, C T Proc Warkshop on Surface Subsidence due to Undergrou:zl Mining, Mc~gantown, 30 Nov-2 Dec 1981, I~3-87. Publ Margantown: West Virginia University, 1982

So far, a total of 44 l o r ~ l subsidence profiles in 22 l o r ~ a l l panels and i0 rom~-andpillar profiles in 5 room-amd-pillar sections have been collected. This paper s~m~rizes the combined results published ~reviously and presents the preliminary results of the predictive models developed. 831163 EVALUATION OF EXISTING PREDICTIVE METHODS FOR MINE SUBSIDENCE IN TP~ US Adamek, V; Jeran, P W Proc Workshop on Surface Subsidence due to Undergrotund Minir~ Mc~gantowm, 30 Nov-2 Dec 1981, P88-99. Publ Mc~gantown: West Virginia University, 1982 Two existing predictive methods were chosen for evaluation: an influence function (Bals Theary) ani a profile function (hyperbolic). These were applied to several field measured subsidence profiles over United States coal mines. The effect of homogeneous versus non-homogeneous overburden on surface subsidence is demonstrated and the utilization of Bals Theory as a subsidence predictive method for both types of overburden is examined. The m a J ~ factor affecting subsidauce profile characteristics is the migration of the inflection point toward the centraline of the long, all panel. A computer program was written to aid in the analysis. Auth. 831164 ~PIRICAL ~ O D S OF SUBSIDENCE PREDICTION - A CASE STUDY Hood, M; Ewy, R T; Riddle, L R Proc W ~ k s h o p on Surface Subsidence due to Undergrour~ H,.i.ning, Margantcwn, 30 Nov-2 Dec 1981, PI00-123. Publ Msrgantc~rn: West Virginia University, 1982 Subsidence ~rofiles above two adjacent panels in Illinois are compared with l~Ofiles l~edicting subsidence behaviour obtained using the (i) National Coal Board method, (ii) the i~ofile function method ~ (ill) the influence function method. The NCB method Iredlcts the maximum subsidence values at the centre of the troughs accurately, but, the overall shapes of these predicted profiles do not match the profiles from the measured data well. A hyperbolic tangent profile fumction is shown to serve as an accurate predictive tool for subsidence behavic%~ in two adjacent l o r 4 ~ panels at Old Ben N ~ b e r 2~ mine in Illinois. This function predicts not only the vertical displacements but also the surface curvatures above both panels. Influence functions are shown to be mc~e ~roblematic, althot~ Ix~tentially mare flexible, in their application than the profile functions.

851165 SUBSIDENCE PROFILE FUNCTIONS DERIVED FROM ~ C H ANISTIC ROCK MASS MODELs - A TENTATIVE ASSESSMENT OF PRACTICAL APPLICABILITY Daemen, J J K; Hood, M Proc Workshop on Surface Subsidence due to Undarground Mining, Morgantown, 30 Nov-2 Dec 1981, P124-141. Publ Margantown: West Virginia University, 1982 A special case of direct connection between a profile function ani an influence function can be based on the use of mechanistic models. In this case the constitutive models describing the rock mass bahaviour define the relation between the bourzlary conditions, the causal effect (is seam convergence), and the resulting effect (ie surface subsidence). This paper considers the first phase of an assesmment of the use of mechanistic subsidence models, tamely the possibilities and problams associated with estimating the lsrge-scale rock parameters needed to use some of the elastic solutions for subsidence calculations by treating the solutions as profile functions. 831166 ~MPIRICAL, CONTINUUM AND BLOCK CAVING C O M B E R MODELS FOR SURFACE SUBSIDETICE Trent, B C Proc W ~ k s h o p on surface Subsidence due to Undergrottmi Mining, Margantownj 30 Nov-2 Dec 1981, P142-147. P~bl Morgantcwn: West Virginia Ur~Iversity, 1982 Reports a study in which an explicit finite difference code was used to model mining subsidence ~ cc~parisons made with the finite element method ar~ with empirical methods (Hdning Engineering Handbook ). 831167 SUBSIDENCE MONITORING - CASE HISTORY Conroy, P J; Gyarmaty, J H Proc Workshop on Surface Subsidence due to Undergroumd Mining, Morgantown, 30 Nov-2 Dec 1981, PIL~3-155o Publ Morgantown: West Virginia University, 1982 Reports a programme of collection and analysis of subsidence and hydrologic data at a longwall coal mine site in eastern Ohio, USA. 831168 SUBSIDENCE MONITORING OVER WESTERN COAL ~INEs Allgaler, F K Proc Wcrkahop on Surface Subsidence due to Undergrottnd Mining, Margantown, 30 Nov-2 Dec 1981, P156-16 3. Publ Morgantown: West Virginia University, 1982 Subsidence monitoring is being conducted at five mines in Colorado and Utah with substantially different mine plans, mining methods, depths of cover, amd topogral~hY. The monitoring procedures used at each site are similar and include designing the monitoring network layout, installing the subsidence mont~nents, initial a n d periodic surveying of the monuments, a ~ processing the survey data. The content of this report is limited to a discussion of the monitoring phase of the USBM l~ogram and includes a s 1 ~ r y of the time requirements far a longwall monit~ing progrsm as well as a general description of the required tasks and equipment. 831169 MONITORING SUBSIDENCE IN THE WEST: PRO~k~MS AND ANALYSIS O'Ro~ke, J E Proc Workshop on surface Subsidence due to Undergrour~ Mining, Margantown, 30 Nov-2 Dec 1981, P164-181. Publ Mar~ntown: West Virginia University, 1982