Experimental Investigation into the Bedding Plane Slip Effect on the Overlying Strata Behavior in Longwall Top Coal Caving of Soft Coal Seam
Table 1
Design of the mechanical property test.
Type
Test subject
Quantity
Description
Compressive strength test
Roof and floor rocks and coal blocks
3/group
The displacement control mode is used by axial loading, the loading rate is 0.2 mm/s, the stress and strain parameters are fully acquired, and the frequency of acquisition is 0.5 s.
Tensile test
Roof and floor rocks and coal blocks
3/group
Using the Brazilian splitting method, a cylindrical specimen (φ50 mm, h = 25 mm) is applied with concentrated loading along the diameter of the specimen, and the specimen breaks in the diameter direction after being subjected to force.
Shear test
Roof and floor rocks and coal blocks
3/group
The shear angles are selected as 20°, 30°, 40°, and 50°, each shear angle has a corresponding set of σ and τ values during the test, and linear fitting is performed according to the σ and τ values.
