fpt 3163 water_science_chapter_4_level_survey

MECHANIZED LAND LEVELING AND IMPROVEMENT FOR IRRIGATED

AGRICULTURE

FPT 3163WATER SCIENCE

En Mohd Fauzie JusohLecturer

Department of Agriculture TechnologyFaculty of Agro-Based Industry

Universiti Malaysia Kelantan (Jeli Campus) Locked Bag No.100, 17600 Jeli, Kelantan.

014-2903025/fauzie.j@umk.edu.my/ Kabin Pensyarah Tingkat Atas Mengadap Padang

Introduction

Surveying Definition:The discipline encompassing all methods of gathering and processing information about our physical earth and its environment.

Types of Surveys:Cadastral Surveys (boundary surveying)Hydrographic Surveys (involving water bodies)Construction Surveys (engineering surveys)Geodetic Surveying (locating points in space)Topographic Surveys (ground-based mapping)Photogrammetric Surveying (aerial methods)

LevelingThe process of finding the elevation at a specified location relative to another known elevation.

Importance of Leveling- For irrigation design in field / nursery.- Precise and accurate control of relative elevations are critical to most construction projects .- Conservation of forest/wildlife

Equipments

Theodolite

Auto Level

Tripod Staff RodBooking

Sheet

Others:pencils, ruler or straight edge, Stakes, hammer, paint, ribbon

DefinitionBench Mark (BM)

A permanent object that has a known elevation/assumed elevation.

Temporary Bench Mark (TBM)

A moveable object that has a known elevation.

Back sight (BS)

The reading on the rod when held on a known or assumed elevation.

Back sights are used to establish the height of instrument.

The first reading from a new instrument stand point.

Fore sight (FS)The reading on the rod when held at a location where the

elevation is to be determined.Foresights are used to establish the elevation at another

location, often a turning point.The last reading from the current instrument station.

Intermediate Foresight (IFS)The reading on the rod when held at a location where the

elevation is to be determined but not used as a turning point.

Any sighting that is not a back sight or fore sight

Turning Point (TP)

A fixed object/station that is used when determining the elevation of other points.

Height of Instrument (HI)

The elevation of the line of sight established by the instrument.

Reduced Level

Height or depth of a point above or below the assumed datum.

Mean Sea Level (M.S.L.)

M.S.L. is obtained by making hourly observations of the tides at any place over a period of 19 years.

Survey Operation

ODINAFRICA/GLOSS Sea Level Training Course - Oostende, Belgium - 13-24 Nov. 2006

Leveling rods

Line of sight

Back sight Fore sight

Gravity Gradient

Basic Principle of Leveling

• Measures height differences between points– Along a line

– Several points from one occupation

bs

fs

Dh = bs - fs

Graduation of a staff.

Difference in elevation between A and B = reading on staff A -reading on staff B

Application

• Well-planned field boundaries and road system in term of road density, sharp curve, road gradients, road uneven, road safety, its impact upon erosion and future mechanization of field operations.

All these factors might affect the costs of installation, excavation and filling.

ROAD MAKING & GRADING: INTRODUCTION

• ROAD MAKING & GRADING IS PROCESS OF MAKING & MAINTAINING ROAD.

• FOR MAKING & GRADING ROAD, WE USE A MACHINE THAT WE CALL MOTOR GRADER & BULDOZER.

• ITS FUNCTION IS TO LEVELLING THE ROAD AND MAKE CAMBER FOR THE ROAD.

OBJECTIVE

• ROAD MAKING & GRADING IS ONE OF METHOD TO MAKE CROP EVACUATION RUNNING SMOOTHLY.

• TO PREVENT SEVERE DAMAGE FOR ROAD

• TO DECREASE LEVEL OF BREAKDOWN FOR OUR MACHINE

• TO MAKESURE THE ROAD CAN BE USED EITHER IN DRY SEASON OR IN RAINY SEASON

MOTOR GRADER

• MACHINE FOR GRADING ROAD.

LEVELLING ROAD

ROAD CAMBERING

BULDOZER• MACHINE FOR MAKING ROAD.

MAKE SURE THE SLOPE < 5°

LEVELLING

• LEVELLING

TO MAKE THE ROAD (MIDDLE) SAME LEVEL

EASIER USED IN DRY AND RAIN SEASON

AVOID SLIPPERY ROAD

MAKE THE ROAD CAN BE USED SMOOTHLY

REMOVE ALL BIG STONES AND ANYTHING THAT BLOCKING ANY OPERATION ONCE WE USING THE ROAD

CAMBERING

• CAMBERING

TO ENSURE WATER NOT STAGNENT ON THE ROAD.

AVOID THE ROAD DAMAGE

TO ENSURE WATER CAN FLOW INTO ROAD SIDE CHANNEL AND BURROW PIT

MAKING ROAD SIDE DRAIN

IDEAL TIME FOR ROAD MAKING & GRADING

NOT IN RAINY SEASON

• AVOID ROAD DAMAGE

• AVOID ROAD SLIPPERY

• TO PREVENT MACHINE STUCK ON ROAD

CONT….

• TO PREVENT DAILY OPERATION DELAYED.

• TO ENSURE THE PROGRAMM IS EFFICIENT

CONT…

IN DRY SEASON

• TO ENSURE DAILY OPERATION STILL CAN RUN.

• AVOID DAMAGING ROAD.

What is SLOPE or GRADIENT ?

How to find or GRADIENT OR SLOPE ?

Gradient : Change in YChange in X

How to find or GRADIENT OR SLOPE ?

100% slope is a 45 degrees slope.

90

95

100

105

110

115

A 2 4 6 8

10

12

14

16

18

20

22

24

26

28

30

32

34

36

38

40

42

44 B

Figure 2

C

D

ROAD SIDE

CHANNEL

SILT PIT

WATER CAN FLOW

INTO SILT PIT

ROAD SIDE DRAIN

POOR DRAINAGE

GOOD ROAD CONDITION

SITUATION AFTER RAIN

SITUATION AFTER RAIN

ROAD-SIDE CHANNEL

NORMAL ROAD PROFILE

ROAD CUTTING BEFORE TERRACING

CUTTING ROAD SIDE DRAIN

CUTTING ROAD SIDE DRAIN

STRENGTHENING ROAD BASE

GRADED ROAD

Rutting Of Road Surface

CONCLUSION

• ROAD MAKING & GRADING IS VERY IMPORTANT IF WE WANT OUR ROAD SYSTEM ALWAYS IN GOOD CONDITION.

• WITH GOOD SYSTEM OF ROAD WE CAN:

MAKE CROP/YIELD EVACUATION FASTLY

PREVENT DAMAGE TO OUR MACHINE.

AVOID ACCIDENT.

ENSURE ROAD ALWAYS CAN BE USED

Others Application

• Sustainable Science

• Natural Resource

- Erosion , Wild Life Protection, Nursery

LEVELING & CONTOURING

Procedure

• The instrument is set up at a convenient position P such that a bench mark (BM) may be observed

• The first reading, made with the staff on a point of known reduced level is known as back sight (BS)

• When the staff is held at points A, B, and C, in turn, is known as intermediate sights (IS)

• If no readings after D is possible, the last reading on D is known as foresight (FS)

Bookings

Rise and Fall Method– Each reading is entered on a different line in the

applicable column, except at change point, where a foresight and backsight occupy the same line.

– The RL is obtained by applying the rise and fall shown by the foresight compared with the previous intersight

– The backsight is taken with the staff still on this point of known level

– The next rise and fall is obtained by comparing this backsight with the next intersight

Exercise 1

The tables given below are readings of a leveling work being carried out at a highway

construction site. You are required to book the reading below using the Rise and Fall

Method. Apply the usual checks to verify your booking. Assume that BM is at an

elevation of 100.00 m at A. The intervals between stations were 30m

Level setting Reading Stations

1 8.75 A

8.66 1

2 7.43 1

7.63 2

8.30 3

8.55 4

3 9.45 4

9.57 5

9.59 6

4 9.40 6

9.35 7

9.24 8

5 8.40 8

8.35 9

8.20 10

8.12 11

6 7.67 11

7.50 12

7 8.40 12

8.67 B

B.S. Int. S. F.S. Rise Fall R.L. Distance Remarks

8.75 100.00 00 A

7.43 8.66 0.09 100.09 30 1

7.63 0.20 99.89 60 2

8.30 0.67 99.22 90 3

9.45 8.55 0.25 98.97 120 4

9.57 0.12 98.85 150 5

9.40 9.59 0.02 98.83 180 6

9.35 0.05 98.88 210 7

8.40 9.24 0.11 98.99 240 8

8.35 0.05 99.04 270 9

8.20 0.15 99.15 300 10

7.67 8.12 0.08 99.27 330 11

8.40 7.50 0.17 99.44 360 12

8.67 0.27 99.17 390 B

Rise and Fall Method

∑ BS = 59.50 ∑ Rise = 0.70 1st RL = 100.00

∑ FS = 60.33 ∑ Fall = 1.53 Last RL = 99.17

0.83 0.83 0.83

StationBack Sight

(B.S)

Inter Sight

(I.S)

Fore Sight

(F.S.)Rise Fall

Reduced

LevelRemarks

1 X1 175.00 BM

2 2.79 0.06

3 2.72

4 X3 X2 0.14 T.P.

5 3.18 0.04

6 3.66 3.24 T.P.

7 3.68 0.02

8 3.72 174.83

9 4.01 3.81 0.09 T.P.

10 X4 0.13

11 4.16

12 4.30 0.14 T.P.

Fill the leveling table given below at the space mark with “X” and calculate the reduced level

for each station. Apply the usual checking on your booking.

Exercise 2

StationBack Sight

(B.S)

Inter

Sight

(I.S)

Fore

Sight

(F.S.)

Rise FallReduced

LevelRemarks

1 2.85 175.00

2 2.79 0.06 175.06

3 2.72 0.07 175.13

4 3.14 2.86 0.14 174.99 T.P.

5 3.18 0.04 174.95

6 3.66 3.24 0.06 174.89 T.P.

7 3.68 0.02 174.87

8 3.72 0.04 174.83

9 4.01 3.81 0.09 174.74 T.P.

10 4.14 0.13 174.61

11 4.16 0.02 174.59

12 4.30 0.14 174.45 T.P.

∑ BS = 13.66 ∑ Rise = 0.13 1st RL = 175.00

- ∑ FS = 14.21 - ∑ Fall = 0.68 - Last RL = 174.45

- 0.55 - 0.55 - 0.55

Rise and Fall Method

The diagram below shows leveling data collected along the straight line from point A to D. The distance between points A, B, C and D is 25 meter. Use the Rise & Fall method to reduce the level and apply the arithmetical check (All unit in meter)

Exercise 3

Contour

• Is a line joining points of equal altitude

• Contour lines – shown on plans as dotted lines, often in distinctive color, overlaying the detail.

• The vertical distance between successive contours is known as the vertical interval.

• The value depends on a. The scale of the plan

b. The use to which the plan is to be put

Contour

• Interpretation of contour– When they are close together, steep gradient exist

– When they are open, the gradients flatten

• Two contour lines of different value cannot intersect, and a single contour cannot split into 2 lines having the same value as itself.

• A contour line must make a closed circuit even it may not be within the area covered by the plan

Contour

• Methods of contouring– Gridding

• Ideal on relatively flat land, comparatively small sites.

• Squares of 10-20 m site are set out (according to the accuracy required) in the form of a grid, the levels are taken at the corners.

• To save setting out all the squares, 2 sets of lines may be established using ranging rods, and to locate any particular square corner the staff man lines himself in, using pairs of ranging rods.

• The reduced levels are then plotted on the plan, which have been gridded in the same manner, and by any suitable means of interpolation the required contours are plotted.

Contour

– Radiating lines

• Rays are set out on the ground from the central point, the directions being known.

• Levels are taken at measured distance from the centre.

• Interpolation is used to give the contour lines, this method is particularly suitable for contouring small hills.

Contour

– Direct contouring

• May be applied in any case, but is used to best advantage in hilly terrain

• The actual contour is located on and marked by colored laths or other convenient means

• The level is set up and levelled at some convenient position, and the height of collimation is established by a back sight onto some point of known level.

Figure shows the level taken from a contour survey using grid method. The grid is set out at 20m x 20m. Form a contour line starting from 56 m with an interval of 2m.

Exercise 4

Contour Construction

Exercise 5

Joint Group using Group Code

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