Civil Engineering Department Politeknik Kota Kinabalu

DCC-20063 Engineering Survey

Group Member
Name No. Matrics
Harry Daniel Tibin 07DKA20F1026
ELEAZER DANIEL JOSEP 07DKA20F1014
Brenda Lisa Bius 07DKA20F1002
NUR HAJARATUL HAZWAD 07DKA20F1030
BINTI BASRI
CASSANDRA DEBORAH 07DKA20F1051
FRANCISCO
 Content No. page
Title 2
Introduction, Theory 2
Objective 2
Method 1
Apparatus & Materials 3
Procedure 3
Tabulation data 4
Method 2
Apparatus & Materials 5
Procedure 5
Tabulation Data 6
Diagram 7
Planning plot 8
Discussion 9
Conclusion 10
Title: Curve Ranging
Introduction:
In the design of roads and railways, straight sections of road or track are connected by
curves of constant or varying radius. The purpose of the curves is to deflect the road
through the angle between the two straights, θ. For those reason, θ is known as the
deflection angle.
In construction surveying, curves have to be set out on the ground for a variety of
purposes. A curve may form the major part of route, it may form a kerb line at a
junction or may be the shape of an ornamental rose bed in a town centre.

Objective:
1. To make necessary computation for setting-out the ranging of simple curve.
2. To make setting-out the ranging of simple curve on site.

Theory:
In the design of roads or railways, straight sections of road or track are connected by
curves of constant or varying radius. The purpose of these curves is to deflect a vehicle
travelling along one of the straights
safely and comfortably through a deflection angle θ to enable it to continue its journey
along the other straight. The two main types shown above are:
Circular curves, curves of constant radius.
Transition curves, curves of varying radius.
A road or railway will usually comprise of a series of straights, circular curves and
transition curves, collectively known as the horizontal alignment.
Method 1: Setting out by tangential angle

Procedure:
1. A theodolite or total station is set up over a point which the picket located.
2. The instrument is then pointed at another point in order to orientate the instrument
to north. If a conventional theodolite is being used it normal to turn the instrument
to north and reset the horizontal angle to zero.
3. Set the bearing of the point in the theodolite and lock it.
4. Use the ranging pole to locate the point that given to make a curve
5. Use measuring tape to measure the distance between of the pole and picket
6. Use the arrow to set the location so the ranging pole can move to the next point
7. Follow the step 3-6 to locate another point until the last point
Tabulation data:
Point CH, m Chord(c), m Tangential Cumulative
angle (ծ) angle /
Deflection
angle
T 476.347 0 0˚ 00’ 00” 0˚ 00’ 00”
T1 480.0 3.653 1˚ 18’ 29” 1˚ 18’ 29”
T2 484.0 4.0 1˚ 25’ 57” 2˚ 44’ 26”
T3 488.0 4.0 1˚ 25’ 57” 4˚ 10’ 23”
T4 492.0 4.0 1˚ 25’ 57” 5˚ 36’ 20”
T5 496.0 4.0 1˚ 25’ 57” 7˚ 02’ 17”
T6 500.0 4.0 1˚ 25’ 57” 8˚ 28’ 14”
T7 504.0 4.0 1˚ 25’ 57” 9˚ 54’ 11”
T8 508.0 4.0 1˚ 25’ 57” 11˚ 20’ 08”
T9 512.0 4.0 1˚ 25’ 57” 12˚ 46’ 05”
T10 516.0 4.0 1˚ 25’ 57” 14˚ 12’ 02”
T11 520.0 4.0 1˚ 25’ 57” 15˚ 37’ 59”
T12 524.0 4.0 1˚ 25’ 57” 17˚ 03’ 56”
U 526.566 2.566 0˚ 55’ 08” 17˚ 59’ 04”

Calculation:
1. IT
=80 Tan(35˚ 58’ 00’ ÷ 2)
=25.968m
2. Chainage to T
= Chainage to I – Length of IT
=502.315 – 25.968
=476.347m
3. Calculate the length of arc L
= 2 π 80 35 ˚ 58' 00 } over {360¿
= 50.219m
Method 2: Setting out curve using offset from tangent line

Procedure:
1. Set the picket at the starting point using hammer
2. Use the measuring tape to measure the distance of tangent line that given
3. Set the ranging pole at the end of tangent line
4. Locate x1 using measuring tape and use the optical square to find the position y1
5. Use measuring tape to find the distance of y1
6. Repeat step 4to 5 to locate y2,y3,y4 using the x2,x3,x4 as point of view.
Tabulation data:
X(m) Y(m)
Y=R-√ R2−x 2
0 0
5 0.156
10 0.627
15 1.419
20 2.540
25 4.007
29.118 5.487

Calculation:
1. IT
=80× Tan(40˚ ÷ 2)
=29.118m
2. Calculate the length of arc L
40
=2 π 80 ×( )
360
=55.851m
Diagram:
Planning plot:
Discussion:
For field work curve ranging using tangential angle, we set up a circular curve
using the data that were given which are the tangent line, length of chord, tangential
angle and so on at the position we chosen to set up. The setting out process begins
with putting the ranging pole away the theodolite using distance calculated
measured with a measuring tape. This is actually tangent length. Then, we make sure
we can see the ranging pole through the theodolite and slowly rotate the theodolite
and move the chaining arrows to the angle we calculate. When we got the angle
correctly, we measure the distance and put the chaining arrow away from the
theodolite with distance calculated. The process is repeated to other point as well
with deflection angle and chord length given.

For fieldwork curve ranging using offset from tangent line, we set up a circular
curve using the data that given which are the tangent line, length of x and length of y
at the position we chosen to set up. The setting process begins with putting the
ranging pole away the picket using the distance given with a measuring tape which
we make a tangent line for curve. Then find all the length of x in between the
tangent line so that we can use the optic square to find the position of y.

The eye level is not perpendicular to the scale of level so the reading taken is
slightly deviation from the actual value. Besides that, the theodolite may not be held
horizontally because our bare eyes cannot make sure the bubble is really in the
middle and the bubble movement is very sensitive. The theodolite is not set up
perfectly vertically from the point which the picket is not in the centre of the point.

In order to overcome the errors, we need to reduce the contact with the
theodolite to minimize the movement so the data will be more accurate. Not only
that, we have to calculate the length considering the slopping land so the chord
length is more reliable to be applied on non-flat surface. Moreover, we need to
make sure the eye level is perpendicular to the scale of the telescope by making the
height of theodolite close to the eye level of the observer. Lastly, we need to make
sure the theodolite is always in a perfectly horizontal and vertically position by trying
to avoid direct contact with the theodolite so the bubble is always in the middle and
we can see the picket is in the middle.

Conclusion:
In conclusion, we are able to set out circular curves on the ground and also
understand the importance of this fieldwork in the engineering sector. By using
theodolite, we are able to demonstrate the use of each instrument for measuring
angles and distances in order to complete this setting out circular curve experiment.
This practical work also provides us the knowledge and experience on the real work
process in the future. From this work field we managed to calculate the deflection
angles, sub-tangent, tangent length, arc length and length of chord by using data
collected from the fieldwork. Any errors that occur from this fieldwork are due to the
sensitivity of the theodolite in which it is hard to get the angle we wanted. However,
modifications are made to overcome this problem in order to achieve the best
results. All of the formulas are used to get the results. By the end of this fieldwork, a
curve is made in order to meet the purpose of this fieldwork in which to deflect the
road through the angle (deflection angle) between the two straights, θ. Overall, it
was a good experience for us as an engineering student who will work in the industry
later on.

Reference:
1. https://www.scribd.com/document/256146768/Curve-Ranging
2. https://fkasa.ump.edu.my/index.php/en/publications-
downloads/pdf-files/laboratory-data-sheet/survey-laboratory/43-
labsheet5-curve/file