Lithology

Volume weight/N∙m3

Rock strata thickness/m

Elasticity modulus/GPa

Poisson’s ratio

Cohesion/ MPa

Internal friction angle/(˚)

Strength of extension/ MPa

Remark

Key strata 2

25,000

8

60

0.4

40

40

7.0

Thickness of stratification is 2 m

Soft rock 2

25,000

8

10

0.3

30

30

1.0

Key strata 1

25,000

8

60

0.4

40

40

7.0

Soft rock 1

25,000

8

10

0.3

30

30

1.0

Coal seam

14,000

3

10

0.2

10

15

1.0

Floor

25,000

5

60

0.3

30

40

7.0