Table 2 Calculated material quantities for similitude Modeling.

From: Investigation on overburden failure and subsurface subsidence characteristics in fully mechanized top-coal caving of “Three-Soft” Thick coal seams

Lithology

Thickness/cm

Sand/kg

gypsum/kg

calcium carbonate/kg

Sawdust/kg

Unconsolidated Layer

97.05

1695.7

164.9

70.7

188.4

Fine-grained sandstone

2.4

48.1

5.6

2.4

/

Sandy mudstone

1.6

32.8

3.3

1.4

/

Fine-grained sandstone

0.6

12.0

1.4

0.6

/

Sandy mudstone

19.9

407.5

40.7

17.5

/

Fine-grained sandstone

2.0

40.1

4.7

2.0

/

Mudstone

0.4

8.3

0.3

0.7

/

Sandy mudstone

3.2

65.5

6.6

2.8

/

No.23 coal seam

0.7

14.7

1.1

0.5

/

Sandy mudstone

1.7

34.8

3.5

1.5

/

Fine-grained sandstone

5.6

112.3

13.1

5.6

/

Sandy mudstone

3.1

63.5

6.3

2.7

/

Fine-grained sandstone

0.7

14.0

1.6

0.7

 

No.21 coal seam

6.0

126.4

9.8

4.2

 

Floor

10.0

200.6

23.4

10.0