Angle of repose

 

Unit weight (kg/m3)

Angle of repose, f

Material

Min

Max

Min

Max

Ashes

6.3

7.9

 

40°

Cement

 

14.1

 

20°

Cement (clinker)

 

14.1

 

30°

Chalk (in lumps)

11.0

12.6

35°

45°

Clay (in lumps)

 

11.0

 

30°

Clay (dry)

18.8

22.0

 

30°

Clay (moist)

20.4

25.1

 

45°

Clay (wet)

20.4

25.1

 

15°

Clinker

 

10.2

 

40°

Coal (in lumps)

 

8.8

 

35°

Coke

 

5.5

 

30°

Copper ore

25.1

28.3

 

35°

Crushed brick

12.6

15.7

35°

40°

Crushed stone

17.3

20.4

35°

40°

Granite

17.3

31.0

35°

40°

Gravel (clean)

14.1

17.3

35°

40°

Gravel (with sand)

15.7

17.3

25°

30°

Hematite iron ore

 

36.1

 

35°

Lead ore

 

50.2

 

35°

Limestones

12.6

18.8

35°

45°

Magnetite iron ore

 

39.3

 

35°

Mangenese ore

25.1

28.3

 

35°

Mud

16.5

18.8

 

0°

Rubblestone

17.3

18.8

 

45°

Salt

 

9.4

 

30°

Sand (dry)

15.7

18.8

30°

35°

Sand (moist)

18.1

19.6

 

35°

Sand (wet)

18.1

20.4

 

25°

Sandstones

12.6

18.8

35°

45°

Shale

14.1

18.8

30°

35°

Shingle

14.1

17.3

30°

40°

Slag

 

14.1

 

35°

Vegetable earth (dry)

14.1

15.7

 

30°

Vegetable earth (moist)

15.7

17.3

45°

50°

Vegetable earth (wet)

17.3

18.8

 

15°

Zinc ore

25.1

28.3

 

35°