Prediction of Subsidence in Steep Seam Mining Based on Probability Integral

The deficiency of subsidence prediction in steep seam mining by the theory of equivalent effect is analyzed: more than 1/2 area of the subsidence basin is caused by the mining of downhill horizontal seam because of the great difference between r1 and r2; r2 is too small that the sinking curve is almost vertical. According to the characteristic of that mining depth is quite different in steep seam mining, a new prediction model with variable r is put forward based on the probability integral model. The model is better than others for steep seam mining and can be adopted widely.