LBYCIVB
EXERCISE NO 6
TOPOGRAPHIC SURVEYING
Student Name:____________________
Group No.: ___________
Group Leader: _______________________
Date Performed: _____________
Date Submitted: _____________
Grade: ___________
1. OBJECTIVE
The objective of this exercise is to conduct a ground method of topographic survey.
2. BACKGROUND
Topography is the configuration (or relief) of a land surface, consisting of its contours
and features, whether natural or man-made. The natural features include streams,
rivers, lakes, swamps, rock outcrops, large trees, hills, valleys and others. Manmade (or cultural) features are the products of people, such as trails, roads,
buildings, bridges, canals, and boundary lines.
Topographic surveys are conducted to locate these natural and cultural features. By
means of various lines and conventional symbols, topographic maps are produced
from survey data. A topographic map is a large-scale representation of a portion of
the earth’s surface showing culture, relief, hydrography, and vegetation. Engineers
use topographic maps as the basis for the planning, layout, and design of most civil
engineering projects. They are useful in determining, for example, the most desirable
and economical location of highways, railroads, canals, pipelines, transmission lines,
reservoirs, and other facilities. Topographic surveys are conducted either by aerial
(photogrammetric) or ground (field) methods, and often a combination of both.
3. INSTRUMENTS AND ACCESSORIES
1 Total Station
2 Stadia rod
2 Range poles
4. LOCATION
To be designated by the laboratory instructor.
5. PROCEDURE
1. Establish instrument stations T1, T2, T3 and T4.
2. Setup and orient the instrument at T1.
3. With the telescope normal, lower clamp locked while upper clamp open, sight
station T4 and record azimuth, bearing and distance of line T1-T4.
4. Sight and record all corners.
5. Foresight T2 and record azimuth of T1-T2. Lock upper clamp and open lower
clamp.
6. Transfer instrument at T2.
7. With telescope inverted, backsight T1. Bring telescope to normal and lock
lower clamp and open upper clamp.
8. Sight all corners that are visible. Measure all distances.
9. Foresight T3 and record azimuth of T2-T3. Measure the distance. Lock upper
clamp and open lower clamp.
10. Transfer the instrument to T3.
11. With telescope inverted, backsight to T2. Bring telescope to normal and lock
lower clamp and open upper clamp.
12. Sight and record all corners that are visible.
13. Foresight T4 and record azimuth of T3-T4. Measure all distances. Lock upper
clamp and open lower clamp.
14. Transfer the instrument to T4.
15. With the telescope inverted, backsight T3. Bring telescope to normal and lock
lower clamp and open upper clamp.
16. Sight and record all corners that are visible. Measure all distances.
17. Sight T1 and record azimuth of T4-T1.
18. Determine the angular error of closure. (AEC)
AEC = (T1-T4) – (T4-T1)  180.
19. Tabulate your data.
20. Plot the features on a large-scale map.
6. DATA SHEET
STATION
Occ. Obs.
T1
T4
Pt. A
Pt. B
Pt. C
Pt. D
Pt. E
Pt. F
Pt. G
Pt. H
T2
T2
T1
Pt. I
Pt. J
Pt. K
Pt. L
Pt. M
Pt. N
Pt. O
Pt. P
T3
T3
T2
Pt. Q
Pt. R
Pt. S
Pt. T
Pt. U
Pt. V
Pt. W
Pt. X
T4
T4
T1
Pt. Y
Pt. Z
Pt. AA
Azimuth
Magnetic Bearing
Distance Remarks
(m)
Compass Box Computed
7. COMPUTATION
8. ILLUSTRATION (Plot the area to scale)
9. COMMENTS/ANALYSIS
10. CONCLUSION
11. RECOMMENDATIONS