In this lecture we will cover Applications of levelling Equipment and procedures Purposes of levelling Some definitions Applications Longitudinal sections and cross sections Plotting the profile Procedure of profile Procedure of cross-section: Plotting the cross-section: Prepared by: Asst. Prof. Salar K.Hussein Mr. Kamal Y.Abdullah Asst.Lecturer. Dilveen H. Omar Erbil Polytechnic University Technical Engineering College Civil Engineering Department

1. Profiles (longitudinal section) & cross sections
1
Erbil Polytechnic University
Technical Engineering College
Civil Engineering Department
Surveying Engineering
Prepared by
Asst. Prof. Salar Khudhur Hussein
Asst. Lecturer Mr. Kamal Yaseen
Asst. Lecturer Ms. Dilveen H. Omar

2. In this lecture we will cover
Applications of levelling
Equipment and procedures
Purposes of levelling
Some definitions
Applications
Longitudinal sections and cross sections
Plotting the profile
Procedure of profile
Procedure of cross-section:
Plotting the cross-section:

3. Profiles (longitudinal section) and
cross sections
The main purposes of the levelling process is Profile (longitudinal)
and cross sections, which can obtain the form and the nature of the
earth's surface along the desired slope line. This line may be straight
or curved and their representation on a map with a suitable scale.
And it is required to obtain(find) form of the earth's surface with
getting the elevations of some points located along the line, in
addition to the distances between those points.
Primary use is for utilities:
1-Highways2-Canals 3-Sewers 4-Water mains 5- Sidewalks
etc..

4. Profiles Layout a 100 m long straight line (starting at your starting point)
and mark out stations by 20 m intervals along it
cross section
Mark out the reference line at 10 m wide cross section perpendicular to
the line at each of the 20 m stations.

5. Introduction abut Profiles (longitudinal section(:-
Profiles are the sections resulting from the leveling
process, which takes place in the longitudinal
direction of the project and along the path project
(central line). This can be done by measuring the
1-distances between the point
2-determining the elevations of those points.

6. Purpose of the profile
1 - Explain the nature of the earth's surface along the
project (along the central line).
2 – Calculate the quantity of volumes in the earth to
construct the project.
Specify the distance between the stations depending on:
1 - The nature of the earth's surface.
2 - The cost of the survey process.
3 – The importance of the project (According to the
accuracy).

8. Site

9. Procedure of profile:
1 - Specify the direction of the longitudinal section (path section) by
selecting the location of the station, which should be equal in distances
(10-15, 20, 25, and 50) m according the nature of the earth's surface.
Scale 1/1000 horizontal and 1/100 vertical

10. Setup the instrument 40 to 50 m from your initial BM and take a BS and
Intermediate Fore Sights (IFS) of each of the 20 m stations and the
associated cross sections

12. 2 - Start leveling process by leveling the stations from known
Bench mark (B.M)and this process is closed in order to
confirm the accuracy of the survey process.

14. Point BS IS FS HI RL Distance Note
1 - BM
HI = RL + BS
R.L=H.I-(I.S,F.S)

16. 3 - Calculated the elevation (RL) of the stations in the
table and are checked for the accuracy of the work.
Point BS IS FS HI RL Distance Note
1 0.663 99.423 98.760 - BM
A 1.946 97.477 0
B 1.008 98.415 20
C 1.153 98.270 40
RL = HI - IS

18. Point BS IS FS HI RL Distance Note
1 0.663 99.423 98.760 - BM
A 1.946 97.477 0
B 1.008 98.415 20
C 1.153 98.270 40
D 1.585 97.838 60

20. Point BS IS FS HI RL Distance Note
1 0.663 99.423 98.760 - BM
A 1.946 97.477 0
B 1.008 98.415 20
C 1.153 98.270 40
D 2.787 1.585 100.625 97.838 60 TP
HI = RL + BS

22. Point BS IS FS HI RL Distance Note
1 0.663 99.423 98.760 - BM
A 1.946 97.477 0
B 1.008 98.415 20
C 1.153 98.270 40
D 2.787 1.585 100.625 97.838 60 TP
E 2.270 98.355 80
F 1.218 99.407 100
G 0.646 99.979 120

23. Point BS IS FS HI RL Distance Note
1 0.663 99.423 98.760 - BM
A 1.946 97.477 0
B 1.008 98.415 20
C 1.153 98.270 40
D 2.787 1.585 100.625 97.838 60 TP
E 2.270 98.355 80
F 1.218 99.407 100
G 0.646 99.979 120
SUM 3.450 7.595 2.231
Check 1
No. of BS = No. of FS
No. of BS = 2
No. of FS = 2

24. Point BS IS FS HI RL Distance Note
1 0.663 99.423 98.760 - BM
A 1.946 97.477 0
B 1.008 98.415 20
C 1.153 98.270 40
D 2.787 1.585 100.625 97.838 60 TP
E 2.270 98.355 80
F 1.218 99.407 100
G 0.646 99.979 120
SUM 3.450 7.595 2.231
Check 2
ΣBS – ΣFS = RL of last point – RL of first point
ΣBS – ΣFS = 3.450 – 2.231 = 1.219
RL last – RL first = 99.979 – 98.760 =1.219

25. Point BS IS FS HI RL Distance Note
1 0.663 99.423 98.760 - BM
A 1.946 97.477 0
B 1.008 98.415 20
C 1.153 98.270 40
D 2.787 1.585 100.625 97.838 60 TP
E 2.270 98.355 80
F 1.218 99.407 100
G 0.646 99.979 120
SUM 3.450 7.595 2.231
Check 3
ΣRL – RL first point = [Σ (No. of IS & FS x HI)]- Σ IS- Σ FS
ΣRL – RL first point = 689.741
[Σ (No. of IS & FSx HI)]- Σ IS- Σ FS
=[99.423x4 + 100.625x3] – 7.595 – 2.231 = 689.741

27. Plotting the profile
After obtaining the levels of the stations on the path of the longitudinal section,
draw the longitudinal section
1 - Draw the elevation differences:
it is a straight horizontal line represents the number of horizontal distances
between the points (stations) along the horizontal line of the paper charts with
suitable scale. and sets those distances on the drawing
2 - Draw the elevation along the vertical line of the paper charts
at a scale larger because the length of the section is big comparing to the
difference in elevation between the stations on the path.
3 - Sets the location of each ground point on the paper charts by using the
coordinates, which are horizontal distance and vertical elevations.

28. 4 - Connects the various points that have been drawn with some
straight lines with considering the slope of the earth's surface
between consecutive points of a regular slope.
5 - Usually the selection of horizontal scale is smaller than the
vertical scale by ten times (1 to 10).
6 - Draws a line below the level of comparing three parallel lines
with an equal distances between each other and used to write
( 1-Stations, 2-Ground elevations, 3- Grade elevations).

30. Grade line:-
It is suggested that the elevations of the ground surface (at
the profile line) is designed by the engineer according to the
technical specifications of the projects. The difference
between the grade elevation and ground elevation at any
station is the amount of cut and fill at that station.
1-Grade A = Ground A
2-Grade B= grade (A) + Slope × Distance(A & B)
3-Grade C=grade(A) + Slope × Distance (A & C

36. Cross-Sections
Cross-section is the section that is (or the elevations are taken) in
the direction perpendicular to the longitudinal section at stations
on both sides of the central line and specify the points of the
establishment perpendicular on the longitudinal section at the
stations either by 1- tape 2- optical square 3- theodolite).

37. Cross-Sections
•Sections at right angles to the centerline of a proposed or
existing project such as a road
Scale 1/50 or 1/100 for both horizontal and vertical axes.

38. Specify the width of the cross-section and the distance between points
depend on the
1 - The nature of the earth's surface.
2 - Width of the project (for example, road width )
The purpose of the cross-section:
1 - Explain the nature of the earth's surface on both sides of the longitudinal
section.
2 - Find the volume quantities of the earth to create the project.

39. Procedure of cross-section:
1 - Specify the direction of the longitudinal section (track section) by
selecting station locations to be at all equal distances (15, 20.25, and
50) m by the nature of the earth's surface.
2 – Specify points of the cross-section on both sides of the longitudinal
section by setting out a perpendicular line from the central points of the
line at the stations with using a right-angled triangle (3,4,5) or (6,8,10)
and specify the distance between the points at every (5 m or 10m
depending on the nature of the ground .

40. 3 - Start the levelling process by taking levels of the stations
from it is known Bench mark and this process is closed to
make sure the accuracy of the scanning process.
4 - Calculate the levels of the stations in the table and the
points located on the right and left of the longitudinal section
is to provide the accuracy of the work.

43. Draw a cross-section
After obtaining the elevations of the stations on the path of the
longitudinal section and the elevation of points, which are
located on both sides of the longitudinal section, and the grade
elevation, the cross sections is drawn.
The cross-sections drawing is similar to longitudinal sections
drawing, but just the same scale is used for both horizontal
distances and elevations of points (because the distance in this
case are not large relative to the elevation difference between
points), but the different scale is used in case of highway.