6 dumpy levels. example of use
- 1. How to use a Dumpy Level Example 1 Find the difference in height between the benchmark and the top of the slope ? Top of Slope Divide hill into 3 spots to make easier Otherwise too far to see or leveling staff not long enough This PowerPoint Presentation is developed and created by :
- 2. How to use a Dumpy Level Example 1 9mAOD Back sight
- 3. How to use a Dumpy Level Example 1 Rotate Dumpy round 9mAOD 2mAOD 2m Back sight Foresight Move Level to new position
- 4. How to use a Dumpy Level Example 1 Move Dumpy to new position 6mAOD 9mAOD 2mAOD Back sight Back sight Foresight
- 5. How to use a Dumpy Level Example 1 Rotate Dumpy round to new position 6mAOD 9mAOD 2mAOD Back sight Back sight Foresight Move Level to new position
- 6. How to use a Dumpy Level Example 1 1mAOD 6mAOD 9mAOD 2mAOD Back sight Foresight Back sight Foresight
- 7. How to use a Dumpy Level Example 1 1mAOD 6mAOD Level of dumpy Level of dumpy = 926m 9mAOD = 922m 2mAOD 1m Back sight Foresight Back sight Foresight 6m 6m + 2m 920m 9m 913m + 9m Height of instrument Height of new Backsight Foresight (Ground point (Height Ground (from (from Level + of Level Dumpy Dumpy Backsight instrument- Level) Level) from Dumpy foresight) Level) Bench mark 913 9 922 2 920 920 6 926 1 925
- 8. How to use a Dumpy Level Example 1 ? Height of instrument Height of new Backsight Foresight (Ground point (Height So the difference in height is Ground (from Level + (from of 925m-913m=12m Level Dumpy Dumpy Backsight instrument- Level) Level) from Dumpy foresight) Level) Bench mark 913 9 922 2 920 920 6 926 1 925
- 9. Example 2 I want to construct a water pipe on the hill by Vigyan Ashram To find the pressure that will result from the pipe I need to know the height difference between point A and point D A= 875mAOD B C D
- 10. Example 2 Height of Foresight Height of new Backsight instrument Ground (from point (Height of (from Dumpy (Ground Level + Level Dumpy instrument- Level) Backsight from Level) foresight) Dumpy Level) Benchmark A=875 B= B= C= C= D= A= 875mAOD B C D
- 11. Example 2 Level of dumpy=879mAOD 4m A= 875mAOD 9m Level of dumpy=871mAOD 1m B 11m B= 870mAOD Level of dumpy=862mAOD 2m C 12m C= 860mAOD D D= 850mAOD
- 12. Example 2 Height of Foresight Height of new Backsight instrument Ground (from point (Height of (from Dumpy (Ground Level + Level Dumpy instrument- Level) Backsight from Level) foresight) Dumpy Level) Benchmark A=875 4 879 9 B= 879-9=870 B= 870 1 871 11 C= 871-11=860 C= 860 2 862 12 D= 862-12= 850
- 13. Example 2 Height of Foresight Height of new Backsight instrument Ground (from point (Height of (from Dumpy (Ground Level + Level Dumpy instrument- Level) Backsight from Level) foresight) Dumpy Level) Benchmark A=875 4 879 9 B= 879-9=870 B= 870 1 871 11 C= 871-11=860 C= 860 2 862 12 D= 862-12= 850 Once you have gone down the hill, check you answer by coming back up the hill Height of Foresight Height of new Backsight instrument Ground (from point (Height of (from Dumpy (Ground Level + Level Dumpy instrument- Level) Backsight from Level) foresight) Dumpy Level) D=850 C= C= B= B= A=
- 14. Example 2 Level of dumpy=879mAOD 4m 9m Level of dumpy=871mAOD A= 875mAOD 1m B 11m Level of dumpy=862mAOD B= 870mAOD 2m C 12m C= 860mAOD D D= 850mAOD
- 15. Example 2 Height of Foresight Height of new Backsight instrument Ground (from point (Height of (from Dumpy (Ground Level + Level Dumpy instrument- Level) Backsight from Level) foresight) Dumpy Level) Benchmark A=875 4 879 9 B= 879-9=870 B= 870 1 871 11 C= 871-11=860 C= 860 2 862 12 D= 862-12= 850 Once you have gone down the hill, check you answer by coming back up the hill Height of Foresight Height of new Backsight instrument Ground (from point (Height of (from Dumpy (Ground Level + Level Dumpy instrument- Level) Backsight from Level) foresight) Dumpy Level) D=850 12 862 2 C=862-2=860 C=860 11 871 1 B=871-1=870 B=870 9 879 4 A=879-4=875
- 16. Example 2 So what was the change in height? Change in height= 25m A= 875mAOD B C D A= 850mAOD
- 17. Summary Questions 1. What is a Dumpy Level Used for? 2. What 2 things can you use to check if things are level? 3. How does a spirit level work? 4. One you have done a backsight reading what would you do next with a dumpy level?