Research Article

The Properties of a Coal Body and Prediction of Compound Coal-Rock Dynamic Disasters

Table 5

Prediction cycle drilling chip amount index S with changing hole depth.

Prediction hole depth (m)12345678910

Prediction times107122115112949479765647
Smax (kg/m)18.5643626427348404230
Smin (kg/m)0.60.80.61.21.81.82.21.611.2
Average value of S (kg/m)2.43.44.84.75.67.17.77.88.27.4