Appraisal of application possibilities of smoothed splines to designation of the average values of terrain curvatures measured after the termination of hard coal exploitation conducted at medium depth

In paper were presented results of average values calculations of terrain curvatures measured after the termination of subsequent exploitation stages in the 338/2 coal bed located at medium depth. The curvatures were measured on the neighbouring segments of measuring line No. 1 established perpendicularly to the runways of four longwalls No. 001, 002, 005 and 007. The average courses of measured curvatures were designated based on average courses of measured inclinations. In turn, the average values of observed inclinations were calculated on the basis of measured subsidence average values. In turn, they were designated on the way of average-square approximation, which was done by the use of smoothed splines, in reference to the theoretical courses determined by the S. Knothe's and J. Bialek's formulas. Here were used standard parameters values of a roof rocks subsidence a, an exploitation rim A_obr and an angle of the main influences range β. The values of standard deviations between the average and measured curvatures σ_C and the variability coefficients of random scattering of curvatures M_C were calculated. They were compared with values appearing in the literature and based on this, a possibility appraisal of the use of smooth splines to designation of average course of observed curvatures of mining area was conducted. (paper)