Research Article

A Study of Safety Coefficient Determination and Support Parameter Optimization Based on Vulnerability Preevaluation

Table 22

Evaluation parameters and scores of the main inclined shaft.

IndictorsValueScoreIndictorsValueScore

Surrounding rock integrity (%)526Mining disturbance time12
Roof strength (MPa)25.488Geological structure2S4
Rib strength (MPa)25.488Buried depth (m)1784
Floor strength (MPa)25.488Major horizontal principal stress (MPa)3.22
Roof rock typeRock3Angle between the axis of the gateway and the major horizontal principal stress (°)42°6
Gateway typeRock3Underground water (ml/min)6008
Dip angle of the surrounding rock (°)155Underground temperature (°C)17.32
Section typeStraight wall semicircle arch6Inspection and maintenanceManual7.5
Section size (m2)24.710Service time6510
Pillar width (m)2
Vulnerability score5.67
Vulnerability preevaluation levelIV
Safety coefficient5.2