Investigation on Prediction Method of Wind Speed Change around the Quarry

摘要

It is considered that land deformation caused by open-cut mining influences wind shift around the quarry. The authors made a statistical study on the influence of topography on the wind speeds at 8 meteorological stations in Iwate Prefecture. It was recognized that the wind speeds at meteorological stations in the mountainous district were affected by the surrounding topography in sprig and fall. It was investigated the correlation between the mean wind speeds and the deviations of inclination. It was concluded that the topography within 1 km-radius affected the wind speeds. It was obtained the next quantitative formulae between the mean wind speeds (V_s V_f: m/s) and the deviations of inclination in the same directions (K_i).V_s = -6. l5K_i + 3.03 (in sprig)V_f = -5.l6K_i +2.59 (in fall)The deviations of inclination K_i are defined as follows. K_I = tan #alpha#_i- sum from 1 to 16 tan #alpha#_j/16 (i=l,2, ……., 16)Where tan #alpha#_i = #DELTA#H_i/L_iHere, #DELTA#H_i is the difference between the altitude of the base point and the highest point within 1 km-radius.L_i is the distance from the base point to the highest point.It became possible to predict the change of mean wind speed around the quarry by the use of these formulae. As a case study was conducted at the quarry that made a plan to be mined-out the whole mountain. As a result, it was predicted that wind system around the quarry would change widely with land deformation caused by open-cut mining.