Survey camp report 2017 at nea kharipati, bhaktapur by suman jyoti

Survey Camp Report 2017-Nov-29 to Dec-05 Prepared by:- Suman Jyoti
ACKNOWLEDGEMENT
This Report is the outcome result of survey camp of Madan Ashrit Memorial Technical
School (Kageswori Manahara, Gothatar-Kathmandu) carried by the Group B, which is held up
to the date of 2017-Nov-29 to 2017-Dec-05
The purpose of this fieldwork was to make the each student independent to carry out the work
in real problem in the field. We think, the purpose is suitable for further work and which make
us to produce the report of the fieldwork in time. We are sincerely indebted to our collage
MAMTS, for providing opportunity to consolidate our theoretical and practical knowledge in
engineering surveying.
I would like to extend my heartfelt gratitude to Er. Niraj Pudasaini and Er. Sanju Subedhi
for their vital encouragement and support in the completion of this project report. This survey
camp meant a lot to me as it gave me a lot of field experience. I would like to thank for, Mr.
Manoj Khadka, who co-operated with me in the matter of guidance to providing instruments.
I would like to express our sincere gratitude to our camp teacher for their helpful suggestions,
friendly behavior and guiding any time during the field work an also providing prompt
comments and rectification necessary before finalization of the report for their
valuable instructions, during the fieldwork, without which it was very difficult to do the work
in the field and to produce the report.
Our camp Instructor:-
1. Er. Niraj Pudasaini (Vice Principle)
2. Er. Sanju Subedhi (Instructor)
3. Er. Ashma Pokhrel (Instructor)
4. Er. Nita Khadka (Instructor)
5. Er. Sushanta Subedhi (Instructor)
6. Mr. Manoj Khadka (Store Keeper)
7. Mr. Anish Bomjom (Teaching Aid)

PREFACE
ThisReportonSurveyCampisthebriefDescriptionoftheworksthatweredoneintheoneweeksduringthe
election time. The main objective of this Survey Camp is to provide an opportunity to
consolidate and update the practical knowledge in engineering.
Surveying in the actual field condition and habituate to work in differentenvironmentwithdifferent
people.
In this Survey Camp, We are supposed to survey a given plot in all its aspect and work on road
alignment, topographic map and bridge alignment with proper X-section, L-Section and its
topography fulfilling all technical requirements. This Report includes the entire description of the
practicalcarriedoutduringtheSurveyCamp.Italsoincludestheprofileandcross-sectionsatdifferentpointsof
theRoadAlignmentandBridgeSiteSurvey.Also,thisreportincludesthedeterminationofvariousorientations
and curvefittingproblems. This Report helps us in ourfurther EngineeringPractice.Thenumber ofproblems
andcalculationsdoneinthisreporthelpsustodealwiththe similar problems in our further Engineering
practice. Everyeffort has been taken to ensure the accuracy in this report. However some errors might have
occurred. We will be verymuch grateful to the viewers who go through this report forbringing such errors in
our notice. Furthermore we would be very thankful for the examiners or viewers for their suggestions in
improving this report.
Our Surveying Team:
1. Suman Jyoti
2. Bishnu p. Bhandari
3. Dipesh Jung Shai
4. Dubdorje Tamang
5. Dhurba Thapa
6. Dinesh Moktan
7. Sunita Khatiwada

ABSTRACT
Surveying is the science and art of determining the relative positions of above, on, or beneath
the surface of earth, and is the most important part of Civil Engineering. The results of surveys
are used to map the earth, prepare navigational charts, establish property boundaries. Develop
data of land used and natural resource information etc. Further survey maintains highways,
railroads, buildings, bridges, tunnels, canals, dams and many more.
Thus, the objective of survey camp was to make us gain the experience in this field by
performing topographic survey in a large area, learning to propose road alignment and select
suitable site for bridge axis.
The report reflects the methodology, observations, and calculations made by thestudents in the
Camp with the corresponding drawings. The large portion of the course covered with elements
of topographic surveying, and then those of road alignment and bridge site survey f follow it.
The main objective of the Survey Camp organized for us is to take an opportunity to consolidate
and update our practical and theoretical knowledge in engineering surveying in the actual field
condition.
In this survey camp we have to prepare a topographic map of the given area, road and bridge
site survey fulfilling all technical requirements. In this regard, we are required to carry out the
necessary field works in our sub-group so that we will get opportunity to the decision on
planning and execution of field works for the preparation of topographic map, road alignment
and bridge site survey. This survey camp helps us to build in our confidence to conduct
engineering survey on required accuracy.

CONTENTS
S.N TITLE
1 Introduction
1.1 Background
1.1.1 Location
1.1.2Site
1.1.3TopographyandGeology
1.1.4Rainfall,ClimateandVegetation
1.1.5DescriptionofWork
1.1.6WorksdetailsandSchedule
1.2 Introduction
1.2.1Surveying
1.2.2Definationofterms
2 TopographicSurveying
2.1LinearMeasurement
2.2TachometrySurveying
2.3TheodoliteTraversing
2.4Methodology
2.4.1BalancingtheTraverse
2.4.2ClosingError
2.5Detailing
2.6Levelling
2.7Contouring
2.8TotalStation
3 BridgeSiteSurvey
3.1Overview
3.2BriefdescriptionofArea
3.3Methodology
4 RoadAlignmentSurvey
4.1Introduction
4.2Curves
4.3Methodology

Chapter One
Introduction
1.1 Background
1.1.1 Location:
Nepal Electricity Authority Training Center, Kharipati,Bhaktapur is about 18 km North East
of Kathmandu. The area to us for survey is about 200 ropanis of land with varieties of land.
(i.e. jungle, vegetation, human settlement etc) .The details of the area is as follows
Country: ‐ Nepal
Region: ‐ Central Development Region
Zone: ‐ Bagmati
District: ‐ Bhaktapur
Our Survey Camp site was located near about 27º41'16"N and 85º27'20"E, at the altitude of
1362 m and about 18 km East of Kathmandu. The area allocated to us for survey is about
292065.62 sq m. of land with variable land features and almost all the man made mentors like
road, sports ground building and pond etc.
It took about twenty 1.5 hour drive to reach Kharipati from Madan Ashrit Memorial Technical
School (Gothatar). The project site is situated in the range of about 1332 m. above mean sea
level.
1.1.2 Site:
i) For Topographic Survey and Road
Alignment
- NEATraining Center
ii) ForBridgesiteSurvey
- NearChaukoteToleRiver,Bansbari

1.1.3 Topography and Geology:
NepalElectricityAuthority(NEA),Kharipatiislocated in the eastern part of Kathmandu valley, It lies
in Bhaktapur districts of Nepal. At the time of the 2011 Nepal census Kharipati had a
population of 8,129 with 1,817 houses in it. It is situated at about a distance of 18 kilometers
from the capital city Kathmandu.
Kharipati has gentle and steep topography differing from places to places. The area contains
ground features ranging from steep slopes to flat grounds. These features were shown by
contours. The geological structure is in good condition, so there is no any geological disasters
and eruption. Soil types are found similar to any other part of Bhaktapur i.e. soft clay, irrigated
by river and well suitable for cultivation.
Especially the low land below the NEA boundary is found to be good for the agricultural
product. The area contains ground features ranging from step slopes to almost flat grounds.
These features were shown by contours. The area also shows a variation in the elevation.
The latitude and longitude of Nepal is as following:
Latitude = 26°22' N to 30°27'
Longitude = 80°04' E to 88°12'
The latitude and longitude of NEA Training Center (Kharipati) is as follow:
Latitude = 27°41'16" N
Longitude = 85°27'20" E
Temperature = Normal
1.1.4 Rainfall, Climate and Vegetation:
The weather is moderate between autumn seasons. During the camp period temperature was
fluctuating from maximum to minimum of it just similar to the annual temperature variation
and rain fall around Kathmandu valley is:-
Temperature: maximum 25o
C to minimum 9o
C. The atmosphere was cool in the morning with
high value of humidity. Most of the empty spaces of the project area were full of vegetation
but without cultivated land except for some land around canteen area. Ordinary grassland
covered most of the areas. Presence of few plants, trees and bushes made environment green
and pleasant.
1.1.5 Description of work:
1. Traversing:
No.ofmajorStation=10 (includingCP1andCP2)
No.ofminorStation=0
2. Detailing:
Area=FromNEAtrainingCanteentobottomgateofboundary. (-asshowninabovefigure)
3. FlyLevelling:

StartingPoint=TopgateofNEATrainingCenter (B.M=1336.000m)
EndingPoint=BottomgateofNEATrainingCenter (T.B.M=1310.525m)
4. RoadAlignment:
Startingpointoftheroad=IP1 (NearboyshostelJunction)
Lengthoftheroad=
CrossSection=3and6mleftandrightof20mintervalonbothsidefromcenterline.
5. BridgeSiteSurvey:
BridgeSpan=13.901m
CrossSection=10mupstreamand10mdownstream.
1.1.6 Work Details and Schedule
The brief description of works done in the survey camp are as presented follows:
Project Title: Survey Camp 2017
Location: NEA-Kharipati, Bhaktapur
Duration: 7 days/ 1 weeks (2017-Nov-29 to Dec-05)
Working Time: 05:30am to 06:00 pm
Surveyed by: Group B
WorkingSchedule
S.N Day Survey Field Work
1 2017-29th
-November Reconnaissance for topographic survey and linear
measurement of traverse.
2 2017-30th
–November Linear measurement of Traverse and Fly levelling
3 2017-01th
–December Angular Measurement and Level transfer to Traverse
4 2017-02th
–December Topography Survey (Detailing)
5 2017-03th
–December Bridge Site Survey (X-section and L-Section detailing)
6 2017-04th
–December Road curve setting and X-section and L-Section detailing
7 2017-05th
-December Presentation / Viva and complete incomplete work
1.2 Introduction
1.2.1 Surveying:
Surveying is defined as the science and technique of determining three dimensional position of
point on above or beneath the surface of the earth by means of angular and
linear measurements.
The application of surveying requires skills as well as knowledge of mathematics, physics, to
some extent, astronomy. The knowledge of surveying is advantageous to many phase of
engineering. The earliest surveys were made in connection with the land surveying. Surveying
is the most essential subject matter before and during all engineering works like civil
engineering works such as designing and construction of highways, water supply systems,
irrigation projects, buildings etc. Land area surveys are made to determine the relative
horizontal and vertical position of topographic features and to establish reference mark to

guide construction. In surveying, all measurement of lengths is horizontal, or else is
subsequently reduce to horizontal distance. The object of survey is to prepare plan or map so
that it may represent the area on a horizontal plane. A plan or map is
horizontal projection of an area and show only horizontal distance of the points. Verticaldista
nces between the points are shown on map by contour lines and are usually represented by
means of vertical sections drawn separately.
The main objectives of surveying courses allocated for civil engineering students is to promote
them the basic knowledge of different surveying techniques relevant to civil engineering works
in their professional practice. The completion of all surveying courses including one week
survey camp work organized by Madan Ashrit Memorial Technical School and will give better
enhancement to students to use all surveying technique covered in lecture classes.
This is a detail report of the works, which were performed by Group B, have seven members,
during the camp period. Briefly explains of the working procedures and technique used by this
group during that camp period. In addition, it also contain observations, calculations, methods
of adjustment of error, main problem during work and their solution, results of all calculations
and their assessments withsomecommentsispresentedinaconciseform:-
In our survey camp, the type of survey that we performed is engineering survey which
includes the preparation of topographic map, in which both horizontal and vertical
controls are necessary. As per instrument used form theodolite traverse survey for fixing
control points, tachometric (Instrument either Total Station or Theodolite) survey for
detailing and triangulation survey for establishing control points in bridge site survey.
Principle of Surveying
The fundamental principles of plane surveying are:
 Working from whole to part:
It is veryessential to establish first a system of control points with higher precision. Minor control points can
then be established by less precise method and details can then be located using minor control
points by running minor traverse. This principle is applied to prevent the accumulation of error
and to control and localize minor error.
 Location of point by measurement from two points of reference:
The relative position of points to be surveyed should be located by measurement from at least
two (preferably three) points of reference, the position of which have already been fixed.
 Consistency of work:
The survey work should performed by keeping consistency in method, instrument, observer
etc. to get desired level of accuracy.
 Independent check:
Everymeasurementtakeninthefieldmustbechecked by some independent field observation so that
the mistake is not passed unnoticely.
 Accuracy required:
Proper method and proper instrument should be used depending upon amount of accuracy
required. Accuracy of angular and linear values should be compatible.
Thus, in our survey camp, survey work is performed by considering the above
fundamental principle of surveying.

1.2.2 Defination of Terms:
1. Bench mark:
A survey mark made on a monument having a known location and elevation, serving as a
reference point for surveying.
2. Traversing:
A traverse may be defined as the course taken measuring a connected series of straight
lines, each joining two points on the ground; these points are called traverse stations.
3. Levelling:
Leveling is the branch of surveying, which is used to find the elevation of given points
with respect to given or assumed datum to establish points at a given elevation or at
different elevations with respect to a given or assumed datum.
4. Contouring:
Contour lines are imaginary lines exposing the ground features and joining the points of
equal elevations.
5. Transition curve:
A transition curve is a curve of varying radius introduced between a straight line and a
circular curve.
6. Triangulation:
The process of determining the location of a point by measuring angles to it from known
points at either end of a fixed baseline, rather than measuring distances to the point
directly.
7. Reduced level:
The vertical distance of a point above or below the datum line is called as reduced level.
8. Back sight reading:
This is the first staff reading that is taken in any set of the instrument after the leveling is
perfectly done. The point is normally taken on the bench mark.
9. Foresight reading:
It is the last reading that in any set of instrument and indicates the shifting of the latter.
10. Intermediate sight reading:
The staff reading between the back sight and foresight.
11. Cross levelling:
The operation of taking level transverse to the direction of longitudinal leveling.
1.2.3 ObjectivesofSurvey Camp:
The main objective of the camp is to provide a basic knowledge of practical implementation of
different survey work, which must be encountered in future. It enhances the practical
knowledge thereby implementing different work and in other side it involves self-assured
feeling everlastingly. It guides to tread on the path ending with success. The main objectives
of the survey camp are as follows:
 To become familiar with the problems that may arise during the fieldworks.
 To became familiar with proper handling of instrument and their functions.
 To become familiar with the spirit and importance of teamwork, as surveying is not a
single person work.
 To complete the given project in scheduled time and thus knows the value of time.
 To collect required data in the field in systematic ways.
 To compute and manipulate the observed data in the required accuracy
and present it in diagrammatic and tabular form in order to understand by others.
 To make capable for the preparation of final report.

Chapter Two
Topographic Surveying
2.1 Linear Measurement
Objectives:-
 To determine accurate distance of two or more segments by ranging process.
 To conduct a survey of a small area by applying techniques of linear measurement and
also work out the area of irregular shape at the site.
Instrument Required:-
 Ranging rod
 Arrow / Peg
Theory:-
The process of determining the distance between one station to another station is termed as
Linear Measurement, i.e. at either horizontal or steeped/inclined surface. The process of
establishing or developing intermediate points between two terminal points or end points on a
straight line is known as ranging.
Procedure:-
 First ranging rods are fixed at start and end station, i.e. exactly in vertical position.
 Then another assistant was standing between (Intermediate station) start and end
station.
 The surveyors placed his eye at the near ranging rod of start station and by looking the
direction of end ranging rods.
 Then after surveyors directed the assistant to move right or left with the help of hand
sight.
 Finally, when these rods are parallel to the start and end station of rods. Now start the
measure distance by tape/chain.
 Again, above same process is repeated after while the traverse cannot complete.
 This process is done by two ways. (start-end and end- start)
 Calculate the average and error distance of two ways measurement.
 After complete measurement, Check the precision which lies in 1 in 1000.
Error = 𝐷1 – 𝐷2
Average =
𝐷1+𝐷2
2
Precision =
𝟏
𝑨𝒗𝒆𝒓𝒂𝒈𝒆
𝑬𝒓𝒓𝒐𝒓
Conclusion:-
We know that direct ranging is possible only when the end stations are inter visible and indirect
ranging is done where end points are not visible and the ground is high.

2.2 Tachometry Surveying
Objectives:-
 Produce the topographic map and detailed plan of the proposed area by using surveying
software (Theodolite, Total Station)
Instrument Required:-
 Total Station or Theodolite
 Stadia Rod
 Peg
 Reflected Prism (i.e. only for total station)
 Tripod Stand
Introduction:-
Tachometry survey is a branch of surveying in which horizontal and vertical distance of points
are obtained by optical measurement avoiding ordinary and slower process of measurement
tape. Tachometric surveys are usually performed to produce contour and details plans for
further work, or to produce coordinates for area and volume calculations. Observation are
usually performed from known survey stations, often established by traversing.
Theory:-
Used a Total Station, able to read distance by reflecting off a prism.
It is now possible to produce plans of large areas that previously would have taken weeks, in a
matter of days. This instrumentation has facilitated the development of this method of detail
and contour surveying into a very slick operation.
Used a Theodolite, able to read distance by sighting from instrument at Stadia rods.
It is also possible now to detailing but it is slowest process than Total Station.
Field work for Traversing:-
a. Reconnaissance: It is done to-
 To locate suitable positions for stations, poorly executed reconnaissance can
result from difficulties at later stages leading waste of time and inaccurate work.
 To obtain overall picture of the area.

b. During selection of station following points should be noted-
 Number of station should be kept minimum as possible.
 Length of traverse legs should be kept as long as possible to minimize effect of
centering error, however too long leg can also result from refraction error.
 Station should be located such that they are clearly inter visible.
 Station should be placed on firm, level ground so that the theodolite/total station
and tripod are supported adequately during measurement.
 Interior angle of the station between traverse legs should not be less than 30° or
should not be around 180° to minimize error during plotting
c. Station marking-
 Station marking needs to be done by the permanent marker for easy allocation
of station throughout the survey period.
 Generally for traverse purpose, wooden pegs are flush into the ground, a nail is
tapped into the top of peg to define exact position of station
 A reference or witnessing sketch of the features surrounding each station should
be prepared especially if the stations are to be left for any time before used or if
they are required again
d. Linear measurement-
 Linear measurement of traverse line will normally be measured by EDM or by
measuring tape.
 During Linear measurement, for precision both way (forward and backward
direction) measurement is carried out and discrepancy should be better than
1:2000
e. For Angular measurement-
 If the internal angles are being read, it is usual to proceed from station to station
round the traverse in an anticlockwise direction
 Generally, more than one set of reading is preferred for higher accuracy
measurement along with both face (right and left face) reading
 If external angles are observed then one should occupy the stations in a
clockwise direction
 When all internal angles are measured, sum of internal angle should be equal to
(2n-4)*90, for external angle (2n+4)*90.

Requirements of Field notes:-
 Accuracy: Field data and reference data should be accurately noted
 Integrity: A single omitted measurement or detail can nullify the use of notes for
plotting. So Notes should be checked carefully for completeness before leaving
 Legibility: Notes can be used only if they are legible. A professional-looking set of
notes is likely to be professional in quality
 Arrangement: Note forms appropriate to the particular survey contribute to accuracy,
integrity, and legibility
 Clarity: Advance planning and proper field procedures are necessary to ensure clarity
of sketches and tabulations and to minimize the possibility of mistakes and omission.
Conclusion:-
We know that when the stations have been sighted, a sketch of the traverse should be prepared
approximately to scale. The stations are given reference letters or numbers. This greatly assists
in planning and checking of field work.
Result:-
Making topographic map and detailed plan of proposed area.
2.3 Theodolite Traversing
Objectives:
 To know the advantages of bearing and their use in various survey works.
 To be familiar with the checks and errors in a closed traverse and solve them.
 To be familiar with various types and methods of traverse surveying for detailing.
 To know well about the traverse computation and be fluent in it.
Instrument Required:
 Theodolite with Tripod Stand
 Tape
 Ranging rod
 Pegs and Hammer
 Prismatic Compass with Stand.
Theory:
Traversing is that type of survey in which member of connected survey lines from the frame
work and the direction and lengths of the survey lines are measured with the help of an angle
measuring instrument and a tape. When the lines form a circuit which ends at the starting points,
it is known as closed traverse. It the circuit ends else. where, it is said to be an open traverse.
The close traverse is suitable for locating the boundaries of lakes, grounds, city maps etc. and
for the survey of large areas, whereas open traverse is suitable for surveying a long narrow strip
of land as required for a road or canal or the coast line.
The main principle of traverse is that a series of the straight line are connected to each other
and the length and direction of each lines are known. The joins of two points of each lines is
known as traverse station and the angle at any station between two consecutive traverse legs is
known as traverse angle.

TheodoliteTraversing:-
Theodolite traversing is a method of establishing control points, their position being determined
by measuring the distances between the traverse stations (which serve as control points) and
the angles subtended at the various stations by their adjacent stations. The traversing in which
the length between two stations of the traverse is measured directly by chaining or taping in
the ground and angle of the station is measured by the theodolite is called theodolite traversing.
Procedure:
- First of all the traverse stations were fixed around the given area to the surveyed keeping
in the ratio of traverse legs 1:2 for major and 1:3 for minor traverse. The stations were
chosen in this place where instrument is easy to setup.
- Measurement of the horizontal distance between one station to another station by using
the tape. And also measure the nearby permanent structure for reference when
unfortunately traverse station is missing.
- Now, with the help of theodolite two sets of horizontal angle between the traverse legs
were measured. i.e. face left and face right.
- The height of the instrument in every set up of theodolite was also measured.
- With the help of prismatic compass, magnetic bearing of one traverse line was
measured.
Norms (Technical specifications):
 Conduct reconnaissance survey of the given area. Form a close traverse (major and
minor) around the perimeter of the area by making traverse station. In the selection of
the traverse station maintain the ratio of maximum traverse leg to minimum traverse
leg less than 1:2formajortraverse.
 Measure the traverse legs in the forward and reverse directions by means of a tape
calibrated against the standard length provided in the field, note that discrepancy
between forward and backward measurements should be better than 1:2000.
 Measure traverse angle on two sets of reading by theodolite. Note that difference
between the mean angles of two sets reading should be within the square root of no of
station times least count of the instrument.
 Determine the R.L. of traverse stations by fly leveling from the given B.M. Perform
two-peg test before the start of fly leveling. Note that collimation error should be less
than 1:10000.
 Maintain equal fore sight and back sight distances to eliminate collimation error. R.L.
of .B.M is 1336
 The Permissible error for fly leveling is (±25√k)mm
 Balance the traverse. The permissible angular error for the sum of interior angles of the
traverse should be less than±√n x 1 minutes for Major Traverse ±√n x 1.5 minutes for
Minor Traverse (n = no. of traverse station).
 For major and minor traverse the relative closing error should be less than 1: 2000
and1: 1000 respectively.
 Plot the traverse stations by coordinate method in appropriate scale, i.e. 1:1000 for
major traverse and 1:500 forminortraverses.

2.4 Methodology:
The methodology of surveying is based on the principle of surveying. They are as follows:
1. Working from whole to part.
2. Independent check.
3. Consistency of work
4. Accuracy Required
The different methodologies were used in surveying to solve the problems arise in the field.
These methodologies are as follows:
a) Reconnaissance (recci):
Reconnaissance (recci) means the exploration or scouting of an area. In survey, it involves
walking around the survey area and roughly planning the number of stations and the position
of the traverse stations. Recci is primarily done to get an overall idea of the site. This helps to
make the necessary observations regarding the total area, type of land, topography, vegetation,
climate, geology and indivisibility conditions that help in detailed planning.
The following points have to be taken into consideration for fixing traverse stations:
 The adjacent stations should be clearly inter visible.
 The whole area should include the least number of stations possible.
 The traverse station should maintain the ratio of maximum traverse leg to minimum
traverseleglessthan1:2forMajorTraverseand1:3forMinorTraverse.
 The steep slopes and badly broken ground should be avoided as far as possible, which
may cause inaccuracy in tapping.
 The stations should provide minimum level surface required for setting up
the instrument.
 The traverse line of sight should not be near the ground level to avoid the refraction.
Taking the above given points into consideration, the traverse stations were fixed. Then two
way taping was done for each traverse leg. Thus, permanent fixing of the control points
completes reconnaissance.
b) Traversing:
Traversing is a type of surveying in which a number of connected survey lines form the
framework. It is also a method of control surveying. The survey consists of the measurement
of
 Angles between successive lines or bearings of each line.
 The length of each line.
There are two types of traverse. They are as follows:
(i) Closed traverse:
If the figure formed by the lines closes at a station i.e. if they form
a polygon or it starts and finishes at the points of known co-ordinatesthen
the traverse is called closed traverse.
(ii) Open traverse:
If a traverse starts and finishes at points other than the starting point or
point of unknown co-ordinates, then the traverse is called open traverse.
Measurement of horizontal and vertical angle:
Two set of horizontal angle was measured at each station and one set of vertical angle. And it
was done in the following way:-
i) One the face left temporary adjustment was done.
ii) After setting zero to the first station the second station was sighted by unclamping
the upper screw.

iii) For better accuracy and exact bisection horizontal angle was measured at the bottom
of the arrow.
iv) And on the same setting or same face vertical angle at both the station was taken.
v) Now again changing the face the horizontal angle was taken and vertical angle too.
vi) Now setting the reading to ninety at the first station again one set of horizontal angle
was taken but the vertical angle is enough, taken earlier.
vii) Before shifting the instrument to the next station the height of instrument was taken.
viii) Similarly the instrument was shifted to other station and in each station one set of
vertical angle and two set of horizontal angle and height of instrument was
measured.
ix) For comparison of the tape distance and the Tachometric distance the stadia reading
(top, mid, bottom) was taken at each station and for the calculation of the reduce
level of each station we need to read mid reading which can be compared with the
level transferred using auto level.
2.4.1 Balancing the traverse:
There are different methods of adjusting a traverse such as Bow ditch’s method, Transit
method, Graphical method, and Axis method. Among them during the survey camp, Bow
ditch’s method was used to adjust the traverse.
The basis of this method is on the assumptions that the errors in linear measurements are
proportional to L and that the errors in angular measurements are inversely proportional to L,
where L is the length of a line. The Bow ditch’s rule is mostly used to balance a traverse where
linear and angular measurements are of equal precision. The total error in latitude and in the
departure is distributed in proportion to the lengths of the sides.
The Bowditch’s Rule is commonly used to balance a traverse where linear and angular
measurements are of equal precision. The total error in latitude and in the departure is
distributed in proportion to the lengths of sides. The Bowditch rule gives the correction as,
TraversethatofPerimeter
LegThatofLengthDeptorLatinErrorTotal
DeptorLatToCorrection
___
)___(*.)_.(___
__.__ 
2.4.2 Closing error:
If a closed traverse is plotted according to the field measurements, the end of the traverse will
not coincide exactly with the starting point. Such and error is known as closing error.
Mathematically,
Closing error (e) = √ {(Ʃ𝐿)2
+(Ʃ𝐷)2
}
Direction, tan θ =ƩD/ƩL
The sign of ƩLand ƩD will thus define the quadrant in which the closing error lies.
The relative error of closure = Error of Closure / Perimeter of the traverse
= e / p
= 1 / (p / e)
The error (e) in a closed traverse due to bearing may be determined by comparing the two
bearings of the last line as observed at the first and last stations of traverse. If the closed
traverse, has N number of sides then,
Correction for the first line = e/N
Correction for the second line = 2e/N
And similarly, correction for the last line = Ne/N = e

In a closed traverse, by geometry, the sum of the interior angles should be (2n-4) x 90˚. Where,
n is the number of traverse sides. If the angles are measured with the same degree of precision,
the error in the sum of the angles may be distributed equally among each angle of the traverse.
2.5 Detailing:
Detailing means locating and plotting relief in a topographic map. Detailing can be done by
either plane table surveying or tachometric surveying. Plane tabling needs less office work than
tachometric survey. Nevertheless, during our camp, we used the tachometric method.
Tachometry
Tachometry is a branch of angular surveying in which the horizontal and vertical distances of
points are obtained by optical means. It is very suitable for steep or broken ground, deep
ravines, and stretches of water or swamp where taping is impossible and unreliable.
The objective of the tachometric survey is to prepare of contour maps or plans with both
horizontal and vertical controls.
The formula for the horizontal distance is (H) = 100*S*cos2
θ
The formula for the vertical distance is (V) = 100 *S*(
Sin2θ
2
) where, S = Staff intercept.
θ = Vertical Angle.
If the angle used is zenithal angle then, θ = Zenithal Angle.
2.6 Levelling:
Leveling is a branch of surveying the object of which is:
(i) To find the elevation of given points with respect to given or assumed datum.
(ii) To establish points at a given elevation or at different elevations with respect
to a given or assumed datum.
(iii) The first operation is required to enable the works to be designed while the
second operation is required in the setting out of all kinds of engineering
works.
(iv) Leveling deals with measurements in a vertical plane.
(v) To provide vertical controls in topographic map, the elevations of the
relevant points must be known so that complete topography of the area.
Two types of leveling were performed at the site, namely direct leveling (spirit leveling)
and indirect leveling (trigonometric leveling).
1. Direct leveling:
It is the branch of leveling in which the vertical distances with respect to a horizontal line
(perpendicular to the direction of gravity) may be used to determine the relative difference in
elevation between two adjacent points. A level provides horizontal line of sight, i.e. a line
tangential to a level surface at the point where the instrument stands. The difference in elevation
between two points is the vertical distance between two level lines. With a level set up at any
place, the difference in elevation between any two points within proper lengths of sight is given
by the difference between the rod readings taken on these points. By a succession of instrument
stations and related readings, the difference in elevation between widely separated points is
thus obtained.
Following are some special methods of direct (spirit) leveling:

Differential leveling:
It is the method of direct leveling the object of which is solely to determine the difference in
elevation of two points regardless of the horizontal positions of the points with respect of each
other. This type of leveling is also known as fly leveling.
Profile leveling:
It is the method of direct leveling the object of which is to determine the elevations of points
at measured intervals along a given line in order to obtain a profile of the surface along that
line.
Cross-sectioning:
Cross-sectioning or cross leveling is the process of taking levels on each side of main line at
right angles to that line, in order to determine a vertical cross-section of the surface of the
ground, or of underlying strata, or of both.
Reciprocal leveling:
It is the method of leveling in which the difference in elevation between two points is accurately
determined by two sets of reciprocal observations when it is not possible to set up the level
between the two points.
Indirect leveling:
Indirect method or trigonometric leveling is the process of leveling in which the elevations of
points are computed from the vertical angles and horizontal distances measured in the field,
just as the length of any side in any triangle can be computed from proper trigonometric
relations.
Two Peg Test:
Before starting the fly leveling, two peg test was carried out to check the accuracy of the level
used. The collimation error was found to be 1: 10000 which satisfied the permissible error limit
(1:10,000).
Temporary adjustments of Level:
a) Setting up the level: The operation of setting up includes fixing the
instrument on the stand and leveling the instrument approximately.
b) L e v e l i n g u p : Accurate leveling is done with the help of foot screws and
with reference to the plate levels. The purpose of leveling is to make the vertical
axis truly vertical and horizontal line of sight truly horizontal.
c) R e m o v a l o f p a r a l l a x : Parallax is a condition when the image formed
by the objective is not in the plane of the cross hairs. Parallax is
eliminated by focusing the eyepiece for distinct vision of the cross hairs and b
yfocusing the objective to bring the image of the object in the plane of cross
hairs.
Booking and reducing levels:
There are two methods of booking and reducing the elevation of points from the observed staff
reading.
Height of the Instrument method:
Arithmetic Check: ∑BS – ∑F.S. = Last R.L. – FirstR.L.
Rise and Fall method:
Arithmetic Check: ∑ BS – ∑ F.S. = ∑ Rise – ∑fall = Last R.L. – FirstR.L.

Level transfer to the major and minor traverse stations:
The R. L of the temporary benchmark was then transferred to the control stations of the major
and minor traverse. The closing error was found to be within the permissible limits. The
misclosure was adjusted in each leg of the leveling path by using the following formula:
Permissible error = ±25kmm.
Where, k is perimeter in Km
Actual Error (e) = ∑B.S – ∑F.S= Last R.L. – First R.L.
Correction ith
leg = -(e x (𝐿1+𝐿2+….+𝐿𝑖)P
Where,𝐿1,𝐿2, 𝐿𝑖 is the length of 1st
,2nd
,ith
leg.
P is perimeter.
Relative Precision= 1/(p/e)
2.7 Contouring:
A contour is an imaginary line, which passes through the points of equal elevation. It is a line
in which the surface of ground is intersected by a level surface. Every fifth contour lines must
be made darken. While drawing the contour lines, the characteristics of the contours should be
approached. The characteristics are as follows:
 Two contours of different elevations do not cross each other except in the case of
an overhanging cliff.
 Contours of different elevations do not unite to form one contour except in the case of
a vertical cliff.
 Contours drawn closer depict a steep slope and if drawn apart, represent a gentle slope.
 Contour at any point is perpendicular to the line of the steepest slope at the point.
 A contour line must close itself but need not be necessarily within the limits of the map
itself.
 U-shape contours indicates the ridge.
 V-shape contours indicates the valley
 Contours lines does not passes through permanent structure.
Taking the reading at the change point on the ground does the indirect method of locating
contours. The interpolation method is used to draw the contour lines. Interpolation of contours
is done by estimation, by arithmetic calculations or by graphical method. The eye estimation
method is extremely rough and is used for small-scale work only. Generally, arithmetic
calculation method of interpolation is used to draw the contour lines and is performed as
follows:
X= (H/V) * Y
where, X= Horizontal distance of the point to be located.
H = Horizontal distance between two guide points.
V = Vertical distance between the two guide points.
Y = Vertical distance between lower elevation point and the point to be located.

2.8 Total station:
Introduction:
A total station is an optical instrument used a lot in
modern surveying and archaeology and, in a minor way,
as well as by police, crime scene investigators, private
accident reconstructionist and insurance companies to
take measurements of scenes. It is a combination of an
electronic theodolite (transit), an electronic distance
meter (EDM) and software running on an external
computer known as a data collector.
With a total station one may determine angles and
distances from the instrument to points to be surveyed.
With the aid of trigonometry and triangulation, the angles
and distances may be used to calculate the coordinates of
actual positions (X, Y, and Z or northing, easting and
elevation) of surveyed points, or the position of the
instrument from known points, in absolute terms.
ComputationandPlotting:
For the calculations as well as plotting, we applied the coordinate method (latitude and
departure method). In this method, two terms latitude and departure are used for calculation.
Latitude of a survey line may be defined as its coordinate lengths measured parallel to
an assumed meridian direction. The latitude (L) of a line is positive when measured towards
north, and termed as Northing and it is negative when measured towards south, and termed as
Southing. The departure (D) of a line is positive when measured towards east and termed as
Easting and it is negative when measured towards south, and termed as Westing. The latitude
and departures of each control station can be calculated using the relation:
Latitude = L Cos θ
Departure=LSin θ
Where, L=distance of the traverse legs
θ =Reduced bearing
If a closed traverse is plotted according to the field measurements, the end of the traverse will
not coincide exactly with the starting point. Such and error is known as closing error.
Mathematically,
Closing error (e) = √ {(Ʃ𝐿)2
+(Ʃ𝐷)2
}
Direction, tan θ = ƩD/ƩL
The sign of ƩLand ƩD will thus define the quadrant in which the closing error lies.
The relative error of closure = Error of Closure / Perimeter of the traverse
= e / p
= 1 / (p / e)
The error (e) in a closed traverse due to bearing may be determined by comparing the two
bearings of the last line as observed at the first and last stations of traverse. If the closed
traverse, has N number of sides then,
Correction for the first line = e/N

Correction for the second line = 2e/N
And similarly, correction for the last line = Ne/N = e
In a closed traverse, by geometry, the sum of the interior angles should be (2n-4) x 90˚. Where,
n is the number of traverse sides. If the angles are measured with the same degree of precision,
the error in the sum of the angles may be distributed equally among each angle of the traverse.
Mathematically,
a)Correction in departure of a side of traverse = - (Total departure misclosure / traverse
perimeter) x length of that side.
b) Correction in latitude of a side of traverse = - (Total latitude misclosure / traverse
perimeter) x length of that side.
Computation Steps:
Here the traverse computation is done in above tabular form. For complete traverse
computations, following steps were carried out:
- The interior angles were adjusted to satisfy the geometrical conditions, ie sum of
interior angles to be equal to (2n-4)x90
- Starting with observed bearing of one line the bearings of all the others lines were
calculated.
- Consecutive co-ordinates (latitude and departure) were calculated. i.e. ∑ L and ∑ D
- Necessary corrections were applied to the latitudes and departures of the lines so that
∑ L=0 and ∑ D=0. The corrections were applied by the transit rule.
Using the corrected consecutive co-ordinates, the independent value were calculated.
- The correct lengths and the correct bearings of the traverse lines were also calculated
using the corrected consecutive co-ordinates.
i.e. true length (l) =√(L^2+D^2 )
true bearing (θ) = tan-1( D/L )
The traverse lines or legs should be passed through the area to be surveyed.
Comments:
The site for survey camping was the NEA Training Center area of Kharipati, Bhaktapur. The
pattern was very suitable because all the facilities for engineering work were available with the
good environment. In morning time the climate is unsuitable for doing work except due to the
cause of frozen, due and cool at least 2 hours. The fooding facilities were hygienic and fresh.
The scheduled was not followed then the teachers and the students were tired of their days
work and could not concentrate on the briefing. In the field, even though the teachers helped
us a lot, we felt that their visiting is not sufficient. We hope that above mentioned problems
will be solved and the upcoming camps will run smoothly without any problems. Some other
problems during the field works were during fly leveling during transferring the R.L. from
given benchmark to the T.B.M. due to the disturbance by climatic condition.
Conclusion:
The given Topography survey camp work was finished satisfactorily within the given span of
time. For surveying, theory can only taken as the introduction but if there
is practice, there will be much gain of knowledge about the techniques of surveying. The
subject survey needs practice as much as possible. Thus, this camp helps us by practicing the
survey work to gain the much essential knowledge as far as possible. It is better to say that it
provides us a confidence to perform survey and apply the techniques at any type of problem
facing during the actual work in the future career.

Chapter Three
BRIDGE SITE SURVEY
3.1 Overview
Objectives:
The adequate functioning of a road depends to a large extent on the effectiveness of the cross
drainage like bridges etc. The main objective of the bridge site survey is to give the students
the preliminary knowledge on selection and planning of possible bridge site and axis for the
future construction of the bridge.
The purpose of the bridge site survey was not only to prepare plan and layout of the bridge
site but also from the engineering point of view, the purpose is to collect the preliminary
data about the site such as normal water flow level, high flood level, geological features of the
ground for planning and designing of the bridge from the details taken during the surveying.
Moreover bridge construction is an important aspect in the development of transportation
network. Surveying is required for topographical mapping, knowledge of longitudinal sections
of the river and cross sections at both the upstream and downstream side of the river for the
construction of a bridge.
Instruments required:
 Tape/ Chain
 Auto Level with Tripod Stand
 Ranging rod
 Staff/Stadia Rods
 Pegs/Arrows and Hammer
 Marker or Enamel
3.2 Brief description of area:
Bridge site survey was conducted over a small spring stream on the Near Chaukote Tole River,
Bansbari -Bhaktapur. The spring collects water etc. coming from the departments and flows
through a ravine formed by hill slopes. Our site was lie below the NEA training departments.
The site was small so easily to crossing river from water level. No huge construction are to be
found near the site. It was plain area/near of terrace field but so many vehicles were obstruct
to our work.
Hydrology, Geology and Soil Condition
Trees surrounded the site. There are no rocks. The nearest ground is suitable for agriculture.
The soil was soft and sandy. It was gray in color. The hill slopes on all sides are not very steep
and are thus geologically stable. There is not much water to be found on the bridge site. The
water is collected only from spring sources.

Technical Specification (Norms):
 A bridge site topographical survey was carried out and the alignment of the bridge axis
was fixed by triangulation.
 Two base lines were measured by tape with two way linear measurement.
Along with these we are also supposed to take L-section and X-section of the river downstream
and upstream.
 A topographic map was prepared by tachometric surveying and longitudinal and cross-
sectional profile of the area was drawn.
3.3 Methodology:
The various methods performed during the bridge site survey were triangulation, leveling,
tachometry, cross section, L-section etc. The brief descriptions of the some methodologies were
given below:-
Recce:
The bridge site was observed and the overview of the placement of axis was made.
Site Selection:
The selection of bridge site is an art and requires considerable investigations. There are various
factors for the selection of bridge site such as geological condition, socio-economic and
ecological aspect etc. Therefore, the sites was chosen such that it should be at well-defined and
stable banks. The site should be on a straight reach of the stream. The site which is sufficiently
away from the confluences of large tributaries, which offers a square crossing & more
advantageous foundation conditions, which is sufficiently away from landslides & flood should
be preferred.
The bridge axis should be so located that it should be fairly perpendicular to the flow direction
and at the same time, the river width should be narrow from the economical point of view and
the free board should be at least 5m.The starting point of bridge axis should not in any way lie
or touch the curve of the road. A site which blends with the topography and landscape will be
aesthetically pleasing. Keeping in minds the above factors, the bridge site was selected. For the
purpose of the shortest span, the stations were set perpendicular to the river flow direction. The
riverbanks were not eroded and were suitable for bridge construction. The chance of change of
direction of river on the selected axis line was nominal.
Fixing of control points and triangulation
First bridge axis was set and horizontal control stations were fixed on either side for detailing.
Distances between stations on the same sides of river i.e. base line were measured with tape
precisely. Then the interconnecting triangles were formed and horizontal angles (two set) were
measured with theodolite. Thus the horizontal control was set out. For vertical control, the level
was transferred from the TBM (located at right bank)to the control points and was transferred
to the stations on the next bank by reciprocal leveling. Triangulation was performed for the
determination of the approximate span of the bridge axis.
The triangulation stations can be taken as the control points for detailing. Two points on either
bank of the river were fixed as control points and one of the sides of the triangle was taken as

the bridge axis. Then two triangles from each bank were fixed. The base line was measured
accurately by two ways linear measurement as well as tachometry and interior angles were
measured by taking two sets of HCR reading by theodolite. The accurate span of bridge was
computed by applying sine rule. To minimize the plotting error as far as possible well-
conditioned triangles were constructed i.e. the angles greater than 30 degree, less then 120
degree and nearer to 60 degree. The best triangle is equilateral triangle.
Topographic survey
The topographic survey of bridge site was done with the help of theodolite. The important
details, which were not included in the cross-section data, were taken. Trigonometric leveling
may be performed to find out the RL of the inaccessible points, but this situation was
not arrived in the given bridge site. All the detailing points were noted for the topographic view
of the bridge site.
Longitudinal Section
The L-Section of the river is required to give an idea about the bed slope, nature of the riverbed,
and the variation in the elevations of the different points along the length of the river. Keeping
the instrument at the control (traverse) stations on the river banks, the staff readings were taken
at different points along the center line of the river up to a 80 meters upstream and 80 m
downstream. The R.L of the traverse stations being known previously; the levels of the
different points on the river were calculated. Then the L-Section of the riverbed was plotted on
a graph paper on scale 1:100 for vertical and 1:1000 for horizontal
Cross-Section
For the cross-section of the river, the staff readings were taken at an interval of 20m. This was
done up to 80m downstream and 80m upstream. While taking the reading the staff was erected
on the bed of river. At every 20m chain age the readings were taken for cross sectioning. The
spot heights were taken where the change in slope was noticed or remarkable points were
noticed such as normal depth level flood depth level, riverbank, etc. Theodolite was used for
this purpose.
Leveling:
TransferringR.L. from B.M. to control points: The R.L of benchmark TBM= 1628.325m(located at
right bank) was given and was transferred to the triangulation stations by fly leveling along
the turning
points by taking the back sight reading to the bench mark which should be within thegiven
accuracy.
Reciprocal Leveling:
When it is required to carry leveling across a river, ravine or any obstacle requiring a long sight
between two points so situated that no place for the level can be found from which the lengths
of foresight & back sight will be even approximately equal, reciprocal leveling must be used
to obtain accuracy and to eliminate the error in instrument adjustment, combined effect of
earth’s curvature & the refraction of the atmosphere, and Variations in the average refraction.
Reciprocal leveling was carried out to transfer the R.L. from BM to A.
True difference in elevation between A and B = H = ha- (hb-e)
Also the true difference in elevation = H = (ha '- e)-hb'
Taking the average of the two differences we get the difference in elevation between A and B.

Comments and Conclusion:
The bridge axis was set keeping in mind all the requisites that the proper site for the bridge has
to be. The result of the computations of the triangulation gave the axis span of 13.901 m. During
the selection of the site all the considerations like geological, socio-economical and
topographical considerations were made and the best site was selected. The site was steep on
both the banks and very little water flowed in there. The site was deep and there was presence
of trees along with bushes. The bridge site survey was conducted to give broad knowledge
about importance of reciprocal leveling, necessities of triangulation concept for fixing bridge
span &to give wide concept about bridge site.

Chapter Four
Road Alignment Survey
4.1 Introduction:
Road is an important infrastructure for development. It occupies a pivotal position in the growth
of developing countries. The advantage becomes particularly evident
when planning the communications system in hilly regions & sparsely populated areas. Road
transport offers quick & assured deliveries, a flexible service free from fixed schedules, door
to door service, permits simpler packing, has a high employment potential etc. The safe,
efficient and economic operation of a highway is governed to a large extent by the care with
which the geometric design has been worked out. Geometric design includes the design
elements of horizontal & vertical alignment, sight distance, X-section components, lateral &
vertical clearances, control of access, etc. The general guide-lines in selecting the alignment &
locating route are:
 Should handle the traffic most efficiently & serve inhabited localities.
 Should have minimum Gradients & curvature, necessary for terrain.
 Should involve least impact on the environment.
 Should be located along the edge of properties. In case of hill road,
 Should attain change in elevation by adopting ruling gradient in most of length.
 Should avoid unstable hill features & areas prone to landslides.
 Should avoid steep terrain.
 Should avoid hair-pin bends.
 Should align preferably on the side of hill exposed to sun during winter.
 Should avoid deep cuttings & costly tunnels.
 Should develop alignment to suit obligatory points like passes, saddles, valleys,
crossing points of major rivers.
In short, road should be short, easy, safe and economic as far as possible. Roads are specially
prepared ways between different places for the use of vehicles, people & animals. In countries
like Nepal, where there are less chances of airways& almost negligible chances of waterway, roads
formamajorpartofthetransportation system. Therefore, it would not be an exaggeration in saying
that the roads have an almost importance.
4.2 Curves:
Curves are generally used on highways and railways where it is necessary to change the
direction of motion. A curve may be circular, parabola or spiral and is always tangential to two
straight directions. Circular curves may be simple, compound, & reverse.
1. Simple Circular Curves:
A simple circular curve is the curve, which consists of a single arc of a circle. It is tangential
to both the straight lines. The elements of simple circular curves are tangent length, external
distance, length of curve, length of long chord, mid-ordinate. The notations used are back
tangent, forward tangent, point of intersection, point of curve, point of tangency, external
deflection angle, normal chord, sub chord etc. The sharpness of the curve is either designated
by its radius or by its degree of curvature. Setting out of curves can be done by two methods
depending upon the instrument used.

i) Linear method: In this method, only a chain or a tape is used. Linear
methods are used when a high degree of accuracy is not required and
the curve is short.
ii) ii) Angular method: In this method, an instrument like Theodolite
is used with or without chain or tape. Before a curve is set out, it is
essential to locate the tangents, point of intersection, point of curves
and point of tangent.
2. Vertical Curves:
A vertical curve is used to join two intersecting grade lines of railways, highways or other
routes to smooth out the chainage in vertical motion .The vertical curve contributes to the
safety, increase sight distance , give comfort in driving and have a good appearance. A grade,
which is expressed as percentage or 1 vertical in N horizontal, is said
to be upgrade or + ve grade when elevation along it increases, while it is termed as downgrade
or -ve grade when the elevation decreases along the direction of motion.
The vertical curves may be of following types:
 Summit curve: It is formed when an upgrade followed by a downgrade, an upgrade
followed by another upgrade, a down grade followed by another down grade.
 Valley curve: It is formed when a down grade followed by an upgrade, an upgrade
followed by another upgrade, a down grade followed by another down grade. In vertical
curve all distance along the curve are measured horizontally and all offsets from the
tangent to the curve are measured vertically. The methods for setting out vertical curve
are:
 The tangent correction method
 Elevation by chord gradient method
 Co-ordinate method
We can use the tangent correction method for setting of curve.
3. Transition Curves:
Transition curve is a curve of varying radius introduced between a straight line and a circular
curve. While the vehicle moves on the straight line of infinite radius to the curve of finite radius,
the passenger feels uncomfortable and even the vehicle may overturn. This is due to the causes
of the centrifugal force couple with the inertia of the vehicle .To avoid these effects , a curve of
changing radius must be introduced between the straight and the circular curve, which is known
as the transition curve. The main functions of the transition curve are as follows:
 To accomplish gradually the transition curve from the tangent to the circular curve, so
that the curvature increased gradually from zero to a specific value.
 To provide a medium for the gradual introduction or change of required super elevation.
Equipment required:
The equipment used in the survey of road alignment were as follows:
 Tape/ Chain
 Auto Level with Tripod Stand
 Ranging rod
 Staff/Stadia Rods
 Pegs/Arrows and Hammer
 Marker or Enamel

Norms (Technical Specifications):
Recci alignment selection was carried out of the road corridor considering permissible gradient,
obligatory points, bridge site and geometry of tentative horizontal and vertical curves.
The road setting horizontal curve, cross sectional detail in 20m interval and longitudinal
profile were prepared.
While performing the road alignment survey, the following norms were strictly followed:
 The road had to be designed starting at the side of Bridge and ending Near tower 3
 If the external deflection angle at the I.P. of the road is less than 3°, curves need not be
fitted.
 Simple horizontal curves had to be laid out where the road changed its direction,
determining and pegging three points on the curve - the beginning of the curve, the
middle point of the curve and the end of the curve along the centerline of the road.
 The radius of the curve had to be chosen such that it was convenient and safe i.e. not
less than 12 m radius.
 The gradient of the road had to be maintained below 12%.
 Cross sections had to be taken at 20 m intervals and at the beginning, middle and end
of the curve, along the centerline of the road - observations being taken for at least 3m
and 6m on either side of the centerline. If undulations are there then section at that
place should be taken.
 The amount of cutting and filling required for the road construction had to be
determined from the L-Section and the cross sections. However, the volume of cutting
had to be roughly equal to the volume of filling.
Design parameters:
The design standards are adopted according to Nepal road standard. The design parameters are
as follows:
S.N Design Parameters Adopted Values
1 Type of Road Single lane Black topped
2 Minimum radius in horizontal curve (m) 15
3 Maximum gradient (%) 12
4 Minimum gradient (%) 1
5 Side slope of cutting 1:1
6 Side slope of embankment 1:1.5
4.3 Methodology:
1. Reconnaissance:
First of all reconnaissance were done by walking through the purposed road alignment, where
the actual alignment of road has to be run. After this pegging was done on the proper position
for instrument station for traversing ensuring that the preceding and succeeding pegs were
visible and simultaneously pegs were marked.
2.HorizontalAlignment:
The locations of the simple horizontal curves were determined carefully considering factors
like the stability of the area, enough space for the turning radius, etc. The I.P.s was fixed so
that the gradient of the road at any place was less than 7%. After determining the I.P.s for the

road, theodolite was stationed at each I.P. and the deflection angles measured. The distance
between one I.P. and another was measured by two way taping.
The horizontal curves were set out by angular methods using theodolite at I.P. and tape.
Horizontal alignment is done for fixing the road direction in horizontal plane. For this, the
bearing of initial line connecting two initial stations was measured using compass. The interior
angles were observed using Theodolite at each IP and then deflection angles were calculated.
Deflection angle = (360 or 180) - observed angle
Fig: Simple circular horizontal curve
Where,
BC: Beginning of curve
EC: End of curve
MC: Midpoint of curve
IP: Apex distance
If +ve, the survey line deflects right (clockwise) with the prolongation of preceding line and
deflects left if –ve (anti-clockwise). The radius was assumed according to the deflection angle.
Then the tangent length, EC, BC, apex distance along with their chainage were found by using
following formulae,
Tangent length (T L) = R x tan (/2)
Length of curve (L.C) = 3.142 x R x /180
Apex distance = R x 1/ (Cos (/2)-1)
Chainage of BC = Chainage of IP – Tangent Length
Chainage of MC = Chainage of BC +Length of Curve/2
Chainage of EC = Chainage of MC + Length of Curve/2
The BC and EC points were located along the line by measuring the tangent length
from the apex and the points were marked distinctly. The radius was chosen such that the
tangent does not overlap. The apex was fixed at the length of apex distance from IP along the
line bisecting the interior angle.
3. Topographic survey
Topographic survey of road corridor was done by taking the deflection angle at each point
where two straight roads meet. The chainage of intersection point, tangent point and middle
points were also taken by linear measurements and applying formula. The staff readings of
each of these points were also taken. The staff points were chosen at every change of slope,
important feature, existing electrical pole etc.
4. Vertical Alignment
Vertical profile of the Road alignment is known by the vertical alignment. In the L-section of
the Road alignment, vertical alignment was fixed with maximum gradient of 12 %. According
to Nepal Road Standard, the minimum gradient of road is about 1% so as to facilitate the flow
of drainage to specified direction. However the maximum of 12% was taken wherever not
possible.
R
Tangent Length, BC1IP = R Tan /2
Apex distance, IPMC1= R(sec/2-1)
Length of chord, BC1MC1EC1=2RSin/2IPBC= IPEC: Tangent length
 : External deflection angle
R: Radius of curve

E
O
B
I

5. Leveling:
The method of fly leveling was applied in transferring the level from the given T.B.M.toallthe
I.Ps.TheR.L.ofbeginnings,mid points andends ofthecurves as well as to the points along the center
line of the road where the cross sections were taken, are taken by tachometry.
6. Longitudinal section:
For the longitudinal section of the road the staff reading was taken at the interval of every 20m
along the centerline of the road. Besides, these staff readings at beginning of the curve, ending
of the curve and apex were also taken. The RL of each point were calculated.
7. Cross-section:
Cross section was run at right angles to the longitudinal profile at 20 m interval on either side
up to 10m distances wherever possible. For this, staffs reading of respective points were taken
using theodolite.
Comments and Conclusion:
Survey of the road alignment was done to make most economical, comfortable, safe and
durable. Extra care is taken to avoid any soil erosion and any other ecological damage. Vertical
and horizontal curves are set according to Road design standards for comfort and other factors.
While setting the road alignment, it should be kept in mind that the minimum IP points should
be taken as far as possible and deflection angles should be minimum as far as possible. The
task was challengeable and tough due to the high altitude along the route.
In spite of the different kinds of obstacles in the field, our group was successful in completing
the fieldwork as well as the office work in time. In the field, we had spent quite some time
discussing the route of the road and also in designing the curves, which led to good results, The
grade change was very sharp which created nuisance in working with the Auto Level Moreover,
after performing this road alignment survey, we were able to build up our confidence in
designing roads at difficult terrain taking factors like economy, convenience and its use into
consideration.

Survey camp report 2017 at nea kharipati, bhaktapur by suman jyoti

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Survey camp report 2017 at nea kharipati, bhaktapur by suman jyoti