Stability Analysis and Fracture Patterns of Hard Main Roof in Longwall Top Coal Caving with Large Mining Height

<div>Uniaxial compression test devices for coal and rock samples. (a) DNS200 electronic universal testing machine. (b) XL2158C stress and strain integrated parameter tester.</div>

Shock and Vibration

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Figure 2

Figure 2: Stability Analysis and Fracture Patterns of Hard Main Roof in Longwall Top Coal Caving with Large Mining Height 