SURVEY CAMPING THEORY REPORT

Survey Camp – 071 Batch – Group 12
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An art and science of determining the relative position of point on above or beneath the surface
of the earth by means of angular and linear measurements is defined as Surveying. The science
of surveying has been developing since the initial stage of human civilization according to their
requirements. The art of surveying preparation of maps has been practiced from the ancient
times and the further advanced until present.
Surveying is the main root for the execution of any civil engineering projects. The process of
surveying consists of fieldwork of taking measurements and office work of continuing and
drawing necessary to the purpose of the survey. The fieldwork is the vital part for any kind of
survey. Field works are performed on the basis of various aspects of surveying and are essential
for a surveyor. As a surveyor, s/he must have sound knowledge, instrument handling skills,
personal traits of friendship, sociability by rational and logical, are able to lead and command
etc. All these factors are required for undertaking a fieldwork successfully. 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, designing and construction of highways,
water supply systems, irrigation projects, buildings etc.
As the success of any engineering is based upon the accurate and complete survey work, an
engineer must therefore be thoroughly familiar with the principle and different methods of
surveying and mapping.
Surveying courses allocated for civil engineering students promote their basic knowledge and
experience on different surveying techniques relevant to civil engineering works in their
professional practice. As the completion of all surveying courses, the B.E. third year students of
2071 batch were on 10 day survey camp at Kharipati, Bhaktapur organized by the Survey
Instruction Committee, Department of Civil Engineering, Himalaya College of Engineering with
a view to give better enhancement to students to use all surveying technique covered in lecture
classes.
1. INTRODUCTION

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The main objective of this survey camp allocated for civil engineering students is to consolidate
and update their basic knowledge of different surveying techniques relevant to civil engineering
works. Working in actual field conditions enhances their theoretical and practical knowledge and
increases their confidence that is beneficial to their professional practice in the near future.
Other objectives of the survey camp can be further listed as below:
 To become familiar with the surveying problems that arises during the field works.
 To became familiar with the parts of the instruments, their functions and handling the
surveying instruments for its use in surveying.
 To become familiar with the spirit and importance of teamwork, as surveying is not a
single person work.
 To compute and manipulate the observed data in the required accuracy and present it in
diagrammatic and tabular form in such a way that it is understood other engineers easily
and gives the layman an idea of what has been done.
 To collect required data in the field in systematic ways.
 To tackle the mistake and incomplete data from the field while in office work.
 To complete the given project in scheduled time and thus gives students a feel of facing
and completing deadlines.
 To be acquainted with the complete method of report preparation.
The specific objectives of the camp to be achieved are:
 To carry out the topographical survey of given area with horizontal and vertical control
and accomplishing the relevant specification and produce a topographic map.
 To transfer the level or vertical control from known point (BM) to TBM near the site and
to find level of different control points.
 To align the road interconnecting the points and find the longitudinal and cross sections.
 To study the details of bridge site and align a bridge axis.
2. OBJECTIVES

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Project Title : Survey Camp 2073
Location : Kharipati, Bhaktapur
Date :
Duration : 11 Days
Working Time : 7:00am to 6:00pm
Class : First morning hour .
Surveyed by : Group 12
2071 Batch of Civil Engineering
Members of Group 12:
NAME ROLL NO.
Muralidhar Nepal 2071/BCE/50
Priyanka Pradhan 2071/BCE/60
Sabin Acharya 2071/BCE/69
Shraddha Thapa 2071/BCE/80
Sukesh Kumar Jha 2071/BCE/89
Working Schedule of our Group
DAY DATE SURVEY FIELD WORK
1 Reconnaissance +Marking of Stations+
Linear measurements
2 Angle measurnment + Major traverse
3 Major traverse + Marking stations for
Minor Traverse
4 Detailling from minor stations
5 Detailing from minor stations + contour
6 Fly Levelling
7 Bridge Survey
8 Road alignment Survey
9 RL transfer to the Major station
10 RL transfer to the Minor station + contour
11 Projection on point plotting on grid line
paper + viva
3. SUMMARY

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Name of the project:
Description of the project:
Location
i) Region : Kharipati and Sallaghari
ii) District : Bhaktapur
iii) Zone : Bagmati
iv) VDC: Bageshwori VDC ward no. 12, NEA Training Centre 16 Km east of
Kathmandu.
Sites:
i. For detail survey work – Kharipati.
ii. Road alignment within the same area.
iii. Bridge survey work – Sallaghari.
Description of work:
Traversing:
i. No of Major Traverse Stations : 18 (including CP1 and CP2)
ii. No of Minor Traverse Stations : 2
Detailing:
i. Plot covered by major traverse in minor traverse :
ii. Area:…………..m2
Road Alignment:
i. Starting point of the road:……
ii. Length of the road: …..m
iii. Cross section:15m on both sides of centre.
iv. Number of intersection points :
Bridge Site Survey:
i. Bridge span:……m
ii. Surveyed area for Topography: 150m upstream and 75m downstream of bridge axis
iii. Longitudinal-section up to 150m on upstream and 75m on downstream
iv. Crosss Section:……m on both sides of longitudinal section.
4. SALIENT FEATURES OF THE PROJECT

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1. TOPOGRAPHYSURVEY
a. Distance Measurement by Total Station Table No. 1.1
b. Horizontal Angle Observation of Major Traverse Table No. 1.2
c. Horizontal Angle Observation of Minor Traverse Table No. 1.3
d. Gales Tables for Major Traverse Table No. 1.4
e. Gales Tables for Minor Traverse -1 Table No. 1.5
f. Gales Tables for Minor Traverse -2 Table No. 1.6
g. Resection for Co-ordinate Transfer Table No. 1.7
h. Two Peg Test Table No. 1.8
i. Fly Leveling Table No. 1.9
j. Adjustment of Reduced Level Table No. 1.10
k. Detailing by Total Station Table No. 1.11
2. BRIDGE SITE SURVEY
a. Bridge Site Triangulation (Major) by Theodolite and
Total station Table No. 2.1
b. Bridge Site Triangulation (Minor) by Theodolite and
Total station Table No. 2.2
c. Gales Table Table No. 2.3
d. RL Transfer from TBM to Bridge Axis Table No. 2.4
e. Reciprocal Leveling Table No. 2.5
f. RL Transfer to Major Stations Table No. 2.6
g. RL Transfer to Minor Stations Table No. 2.7
h. Adjustment of Reduced Level Table No. 2.8
i. Detailing by Tachometry Table No. 2.9
3. ROAD SURVEY
a. Chainage Computation of Curve in Road Alignment Table No. 3.1
b. Leveling for L- Section and X – Section Table No. 3.2
5. LIST OF TABLES

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1. TOPOGRAPHYSURVEY
a. Major Traverse A-I
b. Minor Traverse A-II
c. Topographic Map A-III
a. Topographic Map B-I
b. Longitudinal Profile B-II
c. Cross-section B-III
3. ROAD SURVEY
a. Road Plan C-I
b. Longitudinal Profile C-II
c. Cross-section C-III
6. LIST OF FIGURES

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7.1 Locationand Accessibility
Nepal Electricity Authority Training Center (NEATC), 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 journey from Himalaya College of
Engineering to Kharipati takes about 50 minutes by bus.
7. PROJECT AREA

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 Country: Nepal
 Development Region: Central
 Zone: Bagmati
 District: Bhaktapur
 Location: NEATC premises for Topographical Survey and Road
Alignment Survey Sallaghari for Bridge Site Survey.
7.2 Topographyand Geology
Before starting our job, we should study about the existing position of the project area related to
the natural grid line so that we can relate our result into the natural grid.
The latitude and longitude of Kharipati is as follows:
Latitude: 27ᵒ42’13.8” N
Longitude:85ᵒ28’29”E
Kharipati is the base area of Nagarkot ,The average elevation of Kharipati is 1403m above mean
sea level .
For conducting any type of work we should know about the geology of that area. Geology plays
a vital role for the construction maintenance and rehabilitation of any type of structure.
Geologically Nepal is divided into five zones from south to north, which are extending towards
east west direction and are separated by several geological structures called thrust. For our
concern, the job site falls in “Lesser Himalaya Zone”.
Stratigraphically the central region of Nepal is divided into two major complexes, out of
which one is Kathmandu Complex and another one is Nuwakot complex. The survey camp site
lies in Nuwakot complex. So the geological structures such as fold, Fault Mountains etc. are
preclude at the survey sites. The land in the area is undulated and hilly. The geological structure
is in good condition, so there is no risk of any geological disasters and eruption. Soil types were
found to be good for cultivation. But for the bridge site survey and road survey Sallaghari site
was typically a hilly Terrain and ground composed of soil deposits along with few rockmass.
7.3 Rainfall, Climate and Vegetation
Kharipati lies in the mid-lands of Nepal, hence the climate is mild. It is not too hot in summer
but fairly cool in winter. The camp was held in Kartik which is not the ideal condition because it
is not that much cold. It rains to an average between 200 mm to 375 mm in Bhaktapur area
during the monsoon. There is occasional rainfall during other seasons too.
The average temperature during four seasons at Kharipati, Bhaktapur are as follows:
TEMPERATURE VARIATION TABLE
Season Max. Temperature oC Min. Temperature oC
Summer 25 23
Winter 12 9
Spring 23 16

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Autumn 24 15
7.4 Others
Kharipati, Bhaktapur is a beautiful place. Very pleasing, silent and green
surrounding altogether the natural things made it very wonderful. It is the gateway to the famous
Tourism–site Nagarkot. As we all know that Bhaktapur is known for various historical and
religious activities. There are so many interesting and amazing festivals which attracted all of us,
lots of temples and tourism areas made the camp very wonderful. The population of Bhaktapur is
Newars followed by Brahman, Kshettri etc. The total population of Bhaktapur is about 0.25
millions.
Topographical surveying is the process of determining the positions of natural and artificial
features of the locality by means of conventional signs up on a topographical map. Topographic
surveys are three-dimensional; they provide the techniques of plane surveying and other special
techniques to establish both horizontal and vertical control.
Hence the fieldwork in a topographical surveying consists of three parts.
 It establishes both horizontal and vertical control.
 It locates the contours.
 It also locates the details such as rivers, streams, lakes, roads, houses, and trees etc.
Topographic map is defined as the map representing the positions of all the features in x and y
axes along with the vertical positions with the help of contour lines. In order to prepare the map,
survey was done in the given area using the major and minor traverses. Also the elevations
(R.L.) were transferred from the given benchmark (TBM) firstly to a temporary bench mark
allocated within the survey camp area, then to all the traverse stations and to all the detailed
points. The contour lines were drawn later by performing the necessary calculations. Finally the
detailed Topographic Map including the major and minor traverse, details and contour lines of
the surveyed area was plotted in the given scale. All the calculations in tabular form along with
the topographic map are presented in this report.
8. TOPOGRAHIC SURVEY

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8.1 Objectives
The main Objective is to prepare the topographic map of the given area with horizontal control
and vertical control with required accuracy.
Following target was set while carrying out topographic survey:
 To build up a framework of traverse legs and traverse stations with the visibility of all the
features on the ground at least from each station so that it can be located from the
instrument.
 To fix the alignment of roads, canals, rivers, boundaries etc. when better accuracy is
required.
 To ascertain the co-ordinates of boundary pillars in numerical terms that can be preserved
for future reference such as forest boundary pillars, international boundary pillars etc.
 To prepare a topographic map of the surveyed area for future use during different
engineering project.
 To make contours of a ground taking suitable intervals to provide an exact approximation
of the nature of terrain and feasibility of a project in that area.
 To mark the positions of various important details that can induce effects on the
forthcoming project.
8.2 Brief description of the area
The area, where surveying was performed, is situated at NEA Training Centre, Kharipati. The
major traverse was run throughout the camp area, which cover the whole area of the camp. Our
objective is to prepare a topographic map of the given small area, which is a part of the NEA
training center (Area 1). So, we were assigned to prepare the topographic map of the NEA office
building.
For occupying the detailing portion, two minor traverses were run within the area.
8.3 Norms (Technical specifications)
The technical specification includes all the requirements that should be fulfilled during the
survey work.
HORIZONTAL CONTROL (DISTANCE AND DIRECTION CONTROL):
 In the selection of the traverse station maintain the ratio of maximum traverse leg to
minimum traverse leg less than 2:1 for major and less than 3:1 for minor.

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 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.If traverse leg is
measured in the forward and backward direction with a total station, the precision
should be better than 1:5000.
 Two set Angular measurement (0⁰ set and 90⁰ set) must be taken for major Traverse
while one set Angular measurement (0 set) can be taken for minor traverse. Note that
difference between the mean angles of two sets reading should be within 1’.
 Difference between face right and face left should be differed by ±180⁰±20˝
 Sum of all interior angles and exterior angles must be equal to (2n-4)*90 and
(2n+4)*90 respectively within a tolerance (limit of error) of c√n.
Where, c = 30˝ for major traverse and 1′ for minor traverse
n =no. of observed angles.
Also, relative precision or total error of closure should be less than 1:5000 for
major traverse and 1:3000 for minor traverse.
VERTICAL CONTROL (ELEVATION CONTROL):
 While doing fly leveling, three wire readings must be taken for major traverse and
single hair reading for minor traverse.
 Staff reading should be within 0.6m to 2m.
 Perform two-peg test before the start of fly leveling. Note that collimation error should be
less than 1:10000. Maintain equal foresight and back sight distances to eliminate
collimation error.
 For a closed loop,
Permissible error = 25√k, where k = loop distance in kilometers.
8.4 Equipments
The equipments used in the survey during the preparation of topographic map are as follows:
1. Total station:
The main use of total station is to measure the distance and angle (horizontal and
vertical) by using reflectors with the principle of electronic distance measurement.
2. Level Machine:
The main purpose of the level machine is to establish vertical control of the ground
points. It is mainly used for RL transfer from one point to another point.
3. Ranging Rod:
It is used for sighting the object accurately.
4. Staff:

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It is used as a means to transfer RL of station to different points on the ground. It is a
graduated rod. With the help of three wire reading taken on it the horizontal and the
vertical distances from the instrument station to staff points are calculated by using
trigonometric formulae.
5. Tape:
It is used to measure the horizontal distance between two stations and any two points
when needed. It is also used to measure the height of instrument of Theodolite and
Total station.
6. Arrows:
It is used to mark important points on the ground.
7. Pegs:
It is used to mark the station points/control points on the ground.
8. Hammer:
It is used for hammering the pegs and the arrows whenever required.
9. Permanent marker:
It is used to mark the number and name in the pegs and also to mark the required data in
the field.
10. Compass:
It is used to measure bearing of line in reference to any meridian. Eg.surveyor’s
compass.
8.5 Methodology
The methodology of surveying is based on the principle of surveying. They are as follows:
1. Working from whole to a part
2. Independent check
3. Consistency of work
The different methodologies were used in surveying to solve the problems arise in the field.
These methodologies are as follows:
8.5.1 Reconnaissance [recce]
Recce 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. Recce is primarily done to get an overall idea of the site. This helps to

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make the necessary observations regarding the total area, type of land, topography,
vegetation, climate, geology and intervisibility conditions that help in detailed planning.
It is accompanied by thorough observation of the suitable site for the placement of major
stations. Then at the chosen site, wooden pegs were driven with the hammer if the ground
is soft otherwise it is painted with some paint to mark the major station. The following
points have to be taken into consideration for fixing traverse stations:
 The adjacent stations should be clearly intervisible.
 The whole area should include the least number of stations possible.
 The traverse station should maintain the ratio of maximum traverse leg to
minimum traverse leg less than 2:1 for Major Traverse and 3:1 for Minor
Traverse.
 The angle between the lines should not be less than 30 degree and greater than
120 degree. Thus formed traverse is referred to as well condition.
 The traverse line of sight should not be near the ground level to avoid the
refraction. The stations should provide minimum level surface required for setting
up the instrument.
 Thinking 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 recce.
8.5.2 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.
The directions and the lengths of the survey lines are measured with the help of an angle-
measuring instrument such as theodolite and a tape. If the co-ordinates of the first station
and the bearing of the first line are known, the co-ordinates of all successive points can
be computed as follows:
XB = XA + L Cosθ
YB = YA + L Sinθ
Where, L=Length of traverse leg
θ=Bearing of AB

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There are two types of traverse. They are as follows:
1. 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-ordinates then the traverse is called
closed traverse.
2. OPEN TRAVERSE:
If a traverse starts and finishes at points
other than the starting point or point of
known co-ordinates, then the traverse is
called open traverse.
3. LINK TRAVERSE:
A link traverse is the type of traverse
where an open traverse is linked at its
ends to an existing traverse to form a
closed traverse. The closing line may be
defined by coordinates at the end points
which have been determined by previous
survey.
1. Major Traverse
The skeleton of lines joining those control points, which covers the whole entire area, is
called Major Traverse. Work on Major traverse must be precise. So two-set of reading
should be taken for Major Traverse. For convenience, the readings are taken by setting
the total station at 000’00” for one set and 9000’00” for the second.
The major traverse had 22 control stations including two given control points (CP1 and
CP2). The control stations were named as M1, M2 and so on.
2. Minor Traverse
It is not sufficient to detail the area by enclosing with the help of major traverse. Minor
traverse is that one which runs through the area to make detailing easy. Minor traverse
A Link Traverse
A and E are
known
points

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covers only small area. Less precise work than that of major traverse is acceptable so that
single set reading is sufficient minor traverse. The minor traverse had 6 control stations.
The control stations were named as m1, m2 and so on.
8.5.3 Detailing:
Detailing is the process of locating all the required detail points on the ground for the
preparation of the topographic map or plan with both horizontal and vertical controls.
This was carried out in the field with the help of total station.
TOTAL STATION:
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.
Some total stations also have a GPS interface which
combines these two technologies to make use of the
advantages of both (GPS - line of sight not required
between measured points; Traditional Total Station - high precision measurement
especially in the vertical axis compared with GPS) and reduce the consequences of each
technology's disadvantages (GPS - poor accuracy in the vertical axis and lower accuracy
without long occupation periods; Total Station - requires line of sight observations and
must be set up over a known point or within line of sight of 2 or more known points).
Most modern total station instruments measure angles by means of electro-optical
scanning of extremely precise digital bar-codes etched on rotating glass cylinders or discs

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within the instrument. The best quality total stations are capable of measuring angles
down to 0.5 arc-second. Inexpensive "construction grade" total stations can generally
measure angles to 5 or 10 arc-seconds.
Measurement of distance is accomplished with a modulated microwave or infrared carrier
signal, generated by a small solid-state emitter within the instrument's optical path, and
bounced off of the object to be measured. The modulation pattern in the returning signal
is read and interpreted by the onboard computer in the total station. The distance is
determined by emitting and receiving multiple frequencies, and determining the integer
number of wavelengths to the target for each frequency. Most total stations use a
purpose-built glass Porro prism as the reflector for the EDM signal, and can measure
distances out to a few kilometers, but some instruments are "reflectorless", and can
measure distances to any object that is reasonably light in color, out to a few hundred
meters. The typical Total Station EDM can measure distances accurate to about 3
millimeters or 1/100th of a foot.
Some modern total stations are 'robotic' allowing the operator to control the instrument
from a distance via remote control. This eliminates the need for an assistant staff member
to hold the reflector prism over the point to be measured. The operator holds the reflector
him/herself and controls the total station instrument from the observed point.
Figure: Working Principle of Total Station
The basic principle of Total Station is that the distance between any two points can be
known once the time light takes to travel the distance and back and the velocity of light is
known. Then the following relation, which is already programmed in the memory of the
instrument along with other correction factors, calculates the required horizontal distance
and is displayed on the LCD screen.
SETUP:
1. Place tripod approximately over a known point locking legs at a convenient height so
machine will be at or lower than eye level and the legs are at equal distances from each
other. Eyeball the head of the tripod so it is as close to level as possible.
D = (T/2)*Vel. Of light
station
T/2
Total
station
Station
Target
D

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 Be sure the legs of the tripod are firmly planted into the ground.
 For smooth surfaces (such as concrete, asphalt, or tile), use folding metal tripod
footing to secure the legs.
2. Remove instrument carefully from casing with both hands. Place on top (supporting with
top handle) of tripod and tighten centering screw below platform into instrument,
aligning the three corners of machine and platform. Use sight tangent screw on back side
of LCD display to center the instrument over the exact known point to be surveyed.
POWER AND PREPARATION:
a. Attach one of the batteries to the side of instrument with the clamp side up. Press any one
of the five buttons below the display to turn on machine. It shall beep and the display
should indicate the instrument is not level and must be leveled and indexed (precisely
level internal components).
 To switch power off, hold ESC button and press indicated button that corresponds
to OFF on the display.
 If the battery is at a low level, the following will be displayed, “Battery is low!”-
switch batteries and charge the drained one using provided jack.
 Prior to storing the instrument for its next use, check the status of both provided
batteries. If either is only ENTIRELY drained, charge overnight using given
equipment.
b. Locate the horizontal level bubble above the LCD display. Rotate instrument by
loosening the horizontal clamp and align the display with any two of the leveling screws.
Tighten or loosen the left screw so bubble is in center. Rotate instrument clockwise to the
next two screws and again use the left one to center bubble. Rotate to the final two pair of
screws and center bubble. Check stationary leveling bubble to see if it is center. If not,
repeat previous leveling process.
 If the error message “Tilt out of range” is displayed, it is indicating the
instrument is off-level. Re-level the instrument.
c. To index the vertical circles, loosen the vertical clamp, and manually rotate the telescope
either way twice. The beep should be heard and the zenith angle (ZA vertical angle) will
appear on the LCD display.
d. Loosen the horizontal clamp and rotate the instrument clockwise twice to index the
horizontal circles. The beep is heard again and the horizontal angle (HAR) is displayed.
 Vertical and horizontal indexing has now been completed.

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e. Note the menus displayed. Each option shown on the home page (reached by pressing
ESC) opens a section which contains several (up to 3) pages. To scroll through these
pages to reach other options, press button left of the yellow ESC button that reads PX.
f. Set the target and instrument height by pressing Ht. in S-O mode. Measure the target
height by reading the measurement on the reflector pole at the clamp (set at any arbitrary
height suitable for job). Measure the instrument height by taping the distance from the
black point on side of instrument (level with center of telescope) to the known point on
ground.
 Be sure to note the units used (currently default set at feet and decimal fractions
of feet; see manual to change to metric units) and height of instrument and target
in the field book.
 When using two reflecting poles, be sure to set each at same height
ANGLE MEASUREMENT:
1. Sight the first point (focus with eye piece and align center hairs with center of reflector)
using the horizontal clamp and the fine motion screw. Set the angle to zero by pressing
0SET in THEO mode. Sight the second target and read the HAR on the display.
 If you wish to read the angle by rotating the instrument to the left, press R/L in
THEO mode (display will read HAL or HAR for left or right respectively).
2. For higher accuracy, the average of a number of readings can be taken using repetition.
Sight the first target and press REP in THEO mode. Press BS (back sight) then sight the
second target. Press FS (fore sight) and the angle between the two will be displayed.
Sight the first target again, presses BS, and site the second target again and press FS. The
average of the two readings will be displayed. Repeat up to 10 times for higher accuracy.
3. The slope of the line being shot can be displayed as a percentage by pressing ZA% in
THEO mode. This is read as VA and gives the percentage grade of the line. Press it again
to return to the ZA reading.
 VA% will be displayed when the parameter is set to “Horizontal 0” instead of
“Zenith 0” but performs the same function.
DISTANCE AND ANGLE MEASUREMENT:
This is the most useful and suggested method. The working procedure is described as
follow:
1. Sight target and select for slope, horizontal, or height (SHV) measurement. Press Sdist to
start the measurement and STOP to end. The distance, vertical, and horizontal angle are

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displayed. Press SHV to view the other measurements (Horizontal distance or Height
difference).
2. To measure the horizontal distance several times and display the average, sight the target
and press Hdist in THEO mode. Three measurements are taken and the average (H-A) is
displayed after a few seconds.
The most recently taken data can be recalled and displayed by pressing RCL in the EDM
mode.
CO-ORDINATE MEASUREMENT:
This is not much more useful. So co-ordinate measurement is not suggested for use.
1. In order to begin the coordinate measure, set the initial coordinates of the station. This is
done by pressing the S-O button at the main menu. Then press the Stn-P button on the
second page of the S-O menu. Choose the Input button, then set the initial coordinates
and press ENTER.
2. Sight the target and press COORD in S-O mode, then press STOP to end the
measurement. The coordinates of the target are given with respect to the initial starting
position (0, 0, 0) and designated direction to be North.
MEASURING THE DISTANCE BETWEEN TWO POINTS:
1. Sight the first position and press either Sdist, Hdist, or Vdist in EDM mode to start the
measurement. Stop the measurement by pressing the STOP and sight the next point. Press
MLM on the same page to start the measurement, the press STOP to stop the
measurement. The slope, horizontal, and height difference between the two points is
displayed. This can be repeated as many times as necessary.
2. The slope may be read as a percentage by pressing S% in the same mode after the
missing line measurement has finished. This displays the percent grade between the two
points.
DISTANCE SETTING-OUT MEASUREMENT:
1. To find the direction and distance of a point set out a wanted distance from the instrument
station, sight the reference direction and press 0SET in THEO mode to set the HAR at 0.
Turn total station until the required angle is displayed and locks the horizontal movement.
2. Press ESC to go to basic mode and go to S-O mode. Go to S-O_D for the data and input
the desired distance to set out. Set the reflecting prism in the sighting line and press

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SO_Hd to start the distance measurement. The difference between the desired distance
and the measured distance is displayed on the 1st line.
3. Move the reflecting prism towards or away from the Instrument until H distance becomes
0m to determine the point at the desired distance.
 If there is negative (-) data: Move prism away from Instr.
 If positive (+) data: Move prism towards Instr.
 Press STOP to end the measurement.
CO-ORDINATES SETTING-OUT MEASUREMENT:
a. Set the station coordinates and initial azimuth angle. Press S-O_P in S-O mode and input
the desired coordinates for N and E and press YES to store the data. Press SO_HA in S-O
mode to start the angle measurement. The setting-out horizontal angle, HA is displayed.
Use the horizontal clamp and fine motion screw to turn total station until dHA reads 0°
00’ 00” and lock the clamp.
b. Sight the reflecting prism on the sighting line and press SO_HD and move reflecting
prism until H reads 0m as in part 3 of the distance setting-out measurement.
8.5.4 Discrepancy and linear mis-closure
In order to measure the lengths of the sidesof the traverse, two ways distance
measurement (forward and backward) is done. The difference in values obtained by
forward and backward distance measurements is called discrepancy. The reciprocal of
mean of the two measurements divided by the discrepancy is called precision. Both the
discrepancy and the precision for each traverse leg should be within the given limits.
Mathematically,
Discrepancy = Forward length - Backward length
Linear precision = 1 / (Mean length / Discrepancy)
8.5.5 Adjustment of angular error and bearing
In a closed traverse, by geometry, the sum of the interior angles should be equal to (2n-
4)*90˚ where n is the number of traverse stations. The difference between geometrical
sum and the observed sum is angular error. It may be distributed equally in all angles. If
equal distribution is not possible, larger angles are adjusted with large errors.

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The error (e) in a link traverse due to bearing may be determined by comparing the
known bearing of the line and calculated bearing of the line. If the link traverse, has N
number of sides then,
Bearing Correction for the first line = e/N
Bearing Correction for the second line = 2*(e/N)
And similarly, Bearing correction for the last line = N*(e/N) = e
8.5.6 Balancing the traverse
Consecutive Coordinate: Coordinates of any point calculated with respect to preceding
point is known as Consecutive coordinate.
The latitude (northing) and departure (easting) of every station are referred as its co-
ordinates. After determination of bearing of each line, using known distance, latitude and
departure of each point are calculated using the relation:
Difference in latitude between two points CP1 and CP2,
(N) = L Cos
Where,
L = length of line CP1 – CP2
 = Bearing of line CP1- CP2
Similarly, Difference in departure between these two points CP1 and CP2,
(E) = L Sin
Total coordinates or Independent coordinates: The coordinates of any point calculated
with respect to common origin are known as total coordinate. The origin may be the point
of the same traverse or it may be outside the traverse. The main purpose of calculating
the independent coordinate is to bring the coordinates of all point to positive value of
coordinate so that whole traverse may fall on 1st quadrant.
For accumulating the independent coordinate, the coordinate of must west station of
traverse are assumed some positive values of latitude and departure taking algebraic sum
of latitude and departure, total coordinates can be calculated.
Suppose that the total coordinate of A are(xA,yA). Then total coordinate of B are
(xA+LsinӨ ,yA+LcosӨ).Similarly total coordinate of C are(xB+LsinӨ,yB+LcosӨ) and
so on.
Closing error:
For a closed traverse, theoretically,

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Σ latitude = 0 and Σ departure = 0
But in real practice of traversing, it can’t be achieved which give rise to closing error.
Closing error (Ce) = √ (ΣL2 + ΣD2)
There are different methods of adjusting a traverse such as:
 Bowditch method
 Transit method
 Graphical method
 Axis method
The basis of these methods 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 traverse leg. 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,
8.5.7 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. The constant vertical
distance between consecutive contours is called the contour interval. The contour interval
for a particular contour plan is kept constant; otherwise the general appearance of the
map will be misleading. Every fifth contour lines called index contour must be made
darken.
The factors to be considered for selecting the contour interval are:
 Purpose of map
 Nature of ground.
 Scale of the map.
 Extent of survey.
 Time and fund available.
Correction to lat (or dep) =
Length of corresponding leg
Perimeter of traverse
X Total error in lat (or dep)

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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.
 Contours equally spaced depict a uniform slope. When contours are parallel,
equidistant and straight, these represent an inclined plane surface.
 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.
 A set ring contours with higher values inside depict a hill whereas a set of ring
contours with lower values inside depict a pond or a depression without an outlet.
 When contours cross a ridge or V-shaped valley, they form sharp V-shapes across
them. Contours represent a ridge line, if the concavity of higher value contour lies
towards the next lower value contour and on the other hand these represent a
valley if the concavity of the lower value contour, lies toward the higher value
contours.
 The same contour must appear on both the sides of a ridge or a valley.
 Contours do not have sharp turnings.
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.

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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.
8.5.8 Leveling
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.
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. Leveling deals
with measurements in a vertical plane. To provide vertical controls in topographic map,
the elevations of the relevant points must be known so that complete topography of the
area can be explored.
Temporary adjustments of Level:
The temporary adjustment for a level consists of the following:
a. Setting up the level: The operation of setting up includes fixing the instrument
on the stand and leveling the instrument approximately.
b. Leveling up: 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. Removal of parallax: 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 by focusing the
objective to bring the image of the object in the plane of cross hairs.
Permanent adjustments of Level:
To check for the permanent adjustments of level
two-peg test method should be performed.
Two staffs were placed at A and B of known
length (about 60 m). First the instrument was
setup on the line near B and both staff readings
(Top, Middle, and Bottom) were taken. Then, the
instrument was setup at the middle C on the line
and again both staff readings on A and B was
taken. Then computation was done in order to

Page 26
check whether the adjustment was within the required accuracy or not.
Two types of leveling are used in general Engineering practices, namely direct leveling
(spirit leveling) and indirect leveling (trigonometric leveling).
A. DIRECT LEVELLING:
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 staff 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:
1. DIFFERENTIAL LEVELING
It is the method of direct leveling whose objective is solely to determine the
difference in elevation of two points regardless of the horizontal positions of the
points with respect of each other.
2. PROFILE LEVELING
It is the method of direct leveling the objective 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.
3. 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.
4. 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.
5. FLY LEVELLING:
It is method of transferring RL in a more precise way. In this method the level is
transferred directly by taking BS and FS at every Turning Point. Also, sight
balancing i.e. foresight and backsight distance is kept approximately equal.
B. INDIRECT LEVELING:

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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.
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. Leveling deals with
measurements in a vertical plane.
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. – First R.L.
 Rise and Fall method
Arithmetic Check: ∑ BS – ∑ F.S. = ∑ Rise – ∑fall = Last R.L. – First R.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 = ±25k mm.
Where k is perimeter in Km
Actual Error (e) = ∑BS – ∑F.S. = Last R.L. – First R.L.
Correction for ith leg=e x (L1 + L2 +….+ Li)/P
Where, L1, L2… Liis length of 1st 2nd… ith leg.
P is perimeter
Relative Precision= 1/(p/e)
8.5.9 Resection
To determine the precise position of the new control points using the co-ordinates of the
existing control survey points and survey measurements. The technique that you will use
is referred to as a resection technique. Co-ordinates of control point is determined by the
intersection of lines of sight from the unknown station to other objects whose positions
are already known.Resection is the determination of the observer’s position by means of
observations taken to previously fixed points. There are several methods of resection and
they include:
1. Observing horizontal angles from the unknown point to three known points.

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2. Observing horizontal angles from two unknown points to two known points.
3. Observing horizontal angles from one unknown point to two known points when the
Azimuth of one of them is known.
In the camp we had adopt first method i.e. resection by observing horizontal angles from
the unknown point to three known points.
Figure shows the three points of known coordinate, A B and C, and the fourth point, P,
the coordinates of which are to be established by resection. The three angles x ,y and z
are measured in the field and are measured in a clockwise direction as shown. Three
separate diagrams are shown in figure 4 to take into account three possible positions of P
in relation to A,B and C.TREINSTA FORMULA is used in resection as follows:

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Thus the co-ordinates of p is determined and others points are calculated using concept of
latitude and departure.
8.6 PLOTTING
After computing the co-ordinate of each of the control points, they were made ready to plot. Full
size drawing sheets i.e. A0 sizes were divided into gridlines of 5cm Square. The gridlines were
made with the help of a beam compass. Both major and minor traverses were plotted to 1:1000
scales. The plotted traverse was made at the center of the sheet with the help of least co-ordinates
and highest co-ordinates.
Minor Traverse was plotted in similar way to scale 1:500 over which later detailing by total
station was done.
8.7 COMMENTS
The site for survey camp was the campus area of NEA, kharipati. The pattern was very suitable
because all the facilities for engineering work were available with the good environment of doing
work.
The arrangements of the survey instruments were appreciable although there were some
faulty instruments that made the fieldwork time consuming. Some instruments like theodolite,
levels etc. did not give the accurate reading.
During the Road Alignment Surveying we were provided with the defective Auto Level
that wasted lots of our time in performing the two peg test. We recommend avoiding such
instrument. Due to the faulty recording we were provided with only two tripods instead of three
which resulted in slow surveying. We recommend proper recording.
During the Bridge Site Surveying, we faced problem with using time provided. We were
provided two days for surveying, but a lot of time was consumed by travelling to the site. We
recommend selecting a site near to the camp.
8.8 CONCLUSIONS

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The given Topography survey camp work was finished within the given span of time. The
subject survey needs practice as much as possible. For surveying, theory can be only taken as the
introduction but if there is practice, there will be much gain of knowledge about the techniques
of surveying. 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 through this campaign, we feel within
ourselves that we are ready for any kind of survey works in the actual field in the future.
The topographic maps of different plots prepared by all groups can be compiled to form a single
map of the whole area.

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Bridges are the structures that are constructed with the purpose of connecting two places
separated by deep valleys or gorges or rivers and streams. Bridges are usually a part of road,
making them shorter and hence economical. In countries like Nepal, where the land is undulated
and where there are plenty of rivers, bridges are the most economic and efficient way to join two
places.
Bridge construction is an important aspect in the development of transportation network. For the
construction of bridge, surveying is required for topographical mapping, while the knowledge of
longitudinal section of the river and cross- sections, both the upstream and downstream is
essential. The river flow level in different seasons should also be taken into consideration before
designing a bridge. It is necessary to locate a site, obtain information for design, and furnish lines
and grades for construction.
That is why the task of bridge site surveying has been included in the curriculum of Bachelor's
degree in Civil Engineering in IOE.
Following points should be taken under consideration while selection of bridge axis:
 Narrow and Stable bank
 Straight channel
 Longitudinal gradient of river
 Stable downstream and upstream site and
 Perpendicular to flow direction.
9.1 Objectives
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 in downstream side of the river for the construction
of a bridge.
Following tasks were performed for achieving the objectives:
 The axis of the proposed bridge was aligned.
 Control points were established with the help of triangulation.
 The RL of the control point was determined by fly leveling from the given arbitrary
BM.

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 Reciprocal leveling was performed to transfer level from one bank to another and then
Rl was transferred to remaining control points.
 To perform the longitudinal sectioning of the riverbeds up to 100m upstream and 50m
downstream and cross sectioning at 25m intervals.
9.2 Brief Descriptionof Area
Bridge site survey was done over a kholsi in the woods of TU compound where two hill slopes
formed a deep ravine. Even, there was no flow of water during the time of survey; the flow
direction seemed to be from North-west to South-east.
9.3 Hydrology, Geologyand Soil
The site is surrounded with sloppy ground, which is covered with densely planted shrubs and
bush. The width of river is not so big but flood level covers slightly bigger area. Watermarks on
the rock show that the highest flood level is quite high at sometimes. The site was mossy and
swampy. No huge boulders are to be found near the site. The soil was soft and clayey with brown
color appearance. The hill slopes on both sides are not very steep and are thus geologically
stable. The climatic condition of Kathmandu Valley is sub-tropical and characterized by a
seasonal pattern of monsoon that occurs mainly during rainy season from June to September.
The rainfall is least during winter season. Another important feature of this pattern is largely
variation on amount as well as in place also.
9.4 Norms (Technical Specifications)
The following norms were followed while performing the bridge site survey in the field:
i. Control point fixing as well as determining the length of the bridge axis had to be
done by the method of triangulation. While forming triangles, proper care had to be
taken such that the triangles were well conditioned, i.e. none of the angles of the
triangle were greater than 120° or less than 30°.
ii. The triangulation angle had to be measured on two sets of readings by Theodolite and
the difference between the mean angles of two sets of readings had to be within a
minute.
iii. Computed mean length of bridge axis from two base triangles should be greater than
1:2000.
iv. Transferring the level from one bank to another bank had to be done by the method of
reciprocal leveling.
v. In order to plot the longitudinal section of the river, data had to be taken along the
riverbed 150 m upstream and at least 75 m downstream. The plot for the longitudinal

Page 33
section along the flow line had to be done in a scale of 1:100 for vertical and 1:1000
for horizontal, for cross-section V=H=1:100.
vi. For the cross section profile, data had to be taken at 25 m intervals both upstream and
downstream, and one at the bridge axis. Observation had to cover minimally 25 m
beyond the bank of river on either side.
vii. The topographical map should be plotted in scale of 1:500 with contour lines at
suitable interval (contour interval=1m)
9.5 Equipments
The equipments used in the survey of road alignment were as follows:
 Theodolite
 Staffs
 Ranging rods
 Tapes
 Leveling instruments
 Compass
 Pegs
 Marker
9.6 Methodology
The various methods performed during the bridge site survey were reconnaissance, site
selection, triangulation, tachometry, leveling, cross section, L-section etc. The brief descriptions
of these methodologies were given below:
9.6.1 RECONNAISSANCE AND SITE SELECTION
As the first step, reconnaissance was done for the entire area where the bridge was to be
located. The site for the proposed bridge was selected at a location that was a
continuation of the straight portion of the existing road.
The following things were considered while selecting the bridge site:-
a. The rock outcrops were studied and as they were strong enough to support the bridge and
the dead as well as live loads, the site was found suitable.
b. The slope of the riverbed was gentle at the proposed site. As steep slope means a greater
magnitude of water current, a lot of erosion and wear and tear takes place on the pillars
and the bridge foundation. Hence to avoid that condition, the location of the bridge was
chosen at the place where there was less water current.
c. 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.
d. The location of the bridge was selected in such a way that the heights of the roads joined
by the proposed bridge were almost the same. This prevented a lot of cutting and filling

Page 34
to maintain a gentle gradient. However in doing so, the planned bridge could not be
placed on the location where the breadth of the river was minimum.
e. The high flood level of the river was measured accurately and hence the height of the
bridge above the river was designed taking into consideration the occasional flooding.
f. The bridge was chosen at such a place that it was very convenient for the local use. And
the bridge doesn't deviate from the road. Hence its use is predicted to be huge thus
providing service to a large number of the local people.
g. the sites were chosen such that it should be laid on the very stable bank as far as possible
and not affect the ecological balance of the flora and fauna of the site area
h. The location of the bridge would make it very economical, because for anchoring and
other construction works, the nearby cliffs could be used with minimum strengthening.
Besides, the stones and coarse aggregates could also be used from local sources thereby
decreasing the transportation cost.
9.6.2 TRIANGULATION
For the topographic survey of the bridge site triangulation was done. First the 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 angles
were measured with theodolite. The bridge axis
length or span was calculated by solving the
triangles using the sine rule. Thus the control
points were set out for detailing purpose. To
minimize the plotting error well-conditioned
triangles were constructed i.e. none of the angles of the triangle were greater than 120° or
less than 30°.The best triangle is equilateral triangle.
9.6.3 TACHOMETRY
Tachometry is a branch of angular surveying in which the horizontal and vertical distances of
points are obtained by optical means. Though it has less accuracy, about 1/300 to 1/500, it is
faster and convenient than the measurements by tape or chain. It is very suitable for steep or
broken ground, deep ravines, and stretches of water or swamp where taping is impossible.
The objective of the tachometric survey is the preparation of the topographic map or plan
with both horizontal and vertical controls. For the survey of high accuracy, it provides a
check on the distances measured by tape.
The formula for the horizontal distance, for the tachometer with the additive constant 0.00
and multiplying constant 100.00 is,
H= k x S x Cos2Ө
The formula for the vertical distance is,

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V = (k x S x Sin2Ө)/2
Where, S = staff intercept = Top reading – Bottom reading
k = Multiplying Constant (Generally = 100)
Ө = Vertical angle
The following steps were followed in tachometric survey
a. The instrument was set up over the station and centering/leveling was done
accurately.
b. The vertical distance from the top of the station peg to the center of trunnion axis
of tachometer was measured.
c. The instrument was oriented with reference to a fixed station whose distance and
bearing was predetermined.
d. The staff was held vertically at the nearest available benchmark and it was sighted
by the tachometer to determine the reduced level of the starting point.
e. The staff was held at point of feature to be detailed.
f. Horizontal angle between the reference station and the object point was measured.
g. The vertical angle to the central horizontal wire was observed.
h. The staff readings of the stadia hair were observed.
i. Same procedures were repeated for all the stations.
9.6.4 LEVELING
Level transfer was done in three steps - firstly RL was transferred from the given B.M. to a
point on bridge axis by fly leveling, then with the help of reciprocal leveling, level was
transferred to another bridge axis point and finally RL was transferred to all other control
points.
In differential leveling, the instrument is kept equidistant from the back and forward staff
stations, which causes the neutralization of error resulting in true RL difference.
When it is necessary 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 and back sight will be even approximately equal, reciprocal leveling is
done. Reciprocal leveling helps to eliminate errors such as error in instrument adjustment,
combined effect of earth's curvature and the refraction of the atmosphere and variations in
the average refraction.

Page 36
Fig.: Reciprocal Leveling
Where,
When theodolite is kept near staff held at A
ha= staff reading at station A
hb= staff reading at station B
When theodolite is kept near staff held at B
ha’= staff reading at station A
hb'= staff reading at station B
Then, the true difference in elevation between the two stations A and B is given by
H=½ x [(ha - hb) + (ha'- hb')]
9.6.5 LONGITUDINAL SECTION
The L-section of the river is required to give an idea about the bed slope, nature of he
riverbed, and the variation in the elevations of the different points along the length of the

Page 37
river. Keeping the instrument at the control (traverse) station on the river banks, the staff
readings were taken at different points along the center line of the river at an interval of
about 25 m up to a 150 m upstream and 75m downstream. The RLs of the traverse
stations being known previously; the levels of the different points on the river were
calculated.
9.6.6 CROSS-SECTION
Cross-section of a river at a particular point is the profile of the lateral sides from the
centerline of the river cut. Cross sections were taken to a distance of about 25 m on both
side of the centerline. Staff readings of points along a line perpendicular to the flow of
river were taken from the stations points and the elevations of the points were calculated
using tachometric methods. The cross section can be used to calculate the volume and
discharge of water at the particular section if the velocity at the cross section is known.
9.7 Computation and Plotting
Firstly, the horizontal and vertical control of triangulation stations was determined. Then, other
stations were manipulated to horizontal and vertical control. Bearing of the bridge axis was
measured and the coordinate of a bridge axis point was taken as (1000,2000) to move onto
further calculation. And the calculation is further preceded as usually along with the checking.
Then the coordinates were calculated.
The following tachometric formulas were used for the calculation of the horizontal distance and
R.L. of different points:
Horizontal distance of any point from the traverse station,
H= 100 × S × Cos2
Vertical distance of any point from the traverse station
V= 100 × S × (Sin2)/2
Where, S = staff intercept = Top stadia reading - Bottom stadia reading
 = Vertical Angle
And,
R.L. of a point = R.L. of station + Height of Instrument ± Vertical distance-Middle hair reading
After completing all the computations, the topographic map, the longitudinal section and
the cross section were plotted on the respective scales and are attached with this report.
For topographic map, Scale is 1:500
Contour Interval = 1m
9.8 Comments and Conclusion
The bridge axis was set keeping in mind all the requisites that the proper site for the bridge.
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 inspection of the area
showed that no springs, streams and sewer were discharged into the river up to the 150 m
upstream and 75 m downstream of the axis site. The detailing task was quite difficult for us as
there was dense vegetation and vertical cliff. The flow in river was normal and showed no
danger of changing its direction of flow for the design period of the bridge. The X-section was
read up to the farthest point possible.

Page 38
As we successfully implemented our surveying knowledge for bridge site survey in an existing
feature, we gained high confidence level to work in our professional field.

Page 39
A road is an identifiable route, way or path between two or more places for the transportation of
vehicles, people and animals. Roads are typically smoothed, paved or otherwise prepared to
allow easy travel; though they need not be, and historically many roads were simply
recognizable routes without any formal construction or maintenance.In countries like Nepal,
where there are fewer chances of airways and almost negligible chances of waterway, roads form
a major part of the transportation system. Therefore, it would not be an exaggeration in saying
that the roads have an utmost importance.
Before the construction of the road preliminary survey is done. Road alignment is the
preliminary stage of road construction. Selection of Intersection Points (IP) is the foundation of
construction of road. After that cross section, longitudinal section and formation level are
required.
10.1 Objectives
The basic requirement of an ideal alignment between two terminals stations are that it should be
short, easy, safe and economical. The alignment should be such that it would offer maximum
utility by serving maximum population and products. The utility of a road should be judged from
its utility value per unit length of road. Our chief objective was to obtain this requirement.
The objectives to be achieved during road survey can be listed as below:
 To design the alignment of road in the actual field by fixing IPs
 To calculate the gradient for the vertical curve
 To take the details of the land features of the surrounding area of the planned road
 To prepare the Longitudinal section and cross section of the road at certain required
chainage so that nature of terrain can truly represented in graphs
 To calculate the amount of cutting and filling and estimate the cost of work
10.2 Brief Descriptionof the ProjectArea
The alignment of road was to be set starting from the bridge axis and ending at specified
electricity transmission tower.
10. ROAD ALIGNMENT AND GEOMETRIC DESIGN

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10.3 Hydrology, Geologyand soil
The road had to go along a damp route that was much undulated. The place was damp. There
were no large boulders or rocks of any kind along the proposed site. The alignment run through
the bushy and swampy areas initially but later on the ground was clear. The site has plain areas,
down slope along with up slope. We found soft clayey soil that was very damp which is uniform
throughout the whole length of the road.
10.4 TechnicalSpecifications(Norms)
The technical specification includes all the requirements that should be fulfilled during the
survey work.
 The longitudinal gradient should be below 7% and in extreme cases it can be upto 12%.
 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.
 Radius of horizontal curve should not be less than 12m.
 Two successive curves must not be overlapped.
 Alignment of road should cut contours perpendicularly.
 For a deflection angle less than 3 degrees, setting out of horizontal curve is not necessary.
Deflection angle should be less than 90 degree.
 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.
 We were also supposed to read L-section by leveling at chainages of multiples of 20
along the centerline of the road and also at beginning of curve, middle of curve and end
of curve and X-section by stepping method at 15m on either side of the road.
Longitudinal and cross-sectional profile of the area was drawn. The scales for plotting are
as follows:
 Scale of L-section for road:
o Horizontal : 1:1000
o Vertical : 1:100
 Cross-section for road:
o Horizontal : 1:100
o Vertical : 1:100
 Road corridor plan:1:500

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 Formation width: 10m
10.5 Equipments
The equipments used in the road alignment survey were:
1. Theodolite
2. Staffs and ranging rods
3. Tapes
4. Leveling instruments
5. Compass
6. Pegs and arrows
7. Marker
8. Abney level
10.6 Methodology
The variousmethodsperformedduringthe roadalignmentsurveywere reconnaissance,selectionof IP,
measurementof length,horizontal alignment,vertical alignment,leveling,L-section,X-sectionetc.The
brief descriptionsof these methodologieswere givenbelow:
10.6.1 RECONNAISSANCE:
The reconnaissance survey was performed by taking a thorough walk from starting point
to end point observing the nature of ground and other existing features. A group
discussion was set to come up with a proper alignment.
10.6.2 SELECTION OF INTERSECTION POINTS (IPS):
With help of abney level and self judgment, the intersection point were fixed considering
following points:
 Longitudinal gradient should not exceed 12%.
 Radius of the horizontal curve should not be less than 12m.
 Two successive curves must not be overlapped.
 Deflection angle should be less than 90 degree.
10.6.3 MEASUREMENT OF LENGTHS:

Page 42
The distances between the IPs were measured with the help of tape. Both forward as well
as backward measurement of the distance was carried out. The accuracy for the linear
measurement of the distance between IP is 1:2000.
10.6.4 HORIZONTAL ALIGNMENT:
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 20" Theodolite at each IP and then deflection
angles were calculated.
Deflection angle,  = observed angle-180
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, length of the curve, chainage of beginning of
the curve (BC), chainage of middle of curve (MC), chainage of end of the curve (EC),
apex distance were calculated by using following formulae,

Page 43
Tangent length (T L) = R * tan (/2)
Length of curve (L.C) = 3.142 * R * (/180)
Apex distance = R * 1/ (Cos ((/2)-1)
Chainage of BC = Chainage of IP – TL
Chainage of MC= Chainage of BC +LC/2
Chainage of EC = Chainage of MC + LC/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.
10.6.5 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 lateral 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.
10.6.6 LEVELING
As starting of road was taken at a point in bridge axis, the RL was transferred from that
point to all the I.Ps, beginnings, mid points and ends of the curves as well as to the points
along the center line of the road where the cross sections were taken.

Page 44
10.6.7 LONGITUDINAL SECTION
The L-Section of the road is required to give the road engineer an idea about the nature of
the ground and the variation in the elevations of the different points along the length of the
road and also to determine the amount of cutting and filling required at the road site for
maintaining a gentle slope. In order to obtain the data for L-Section, staff readings were
taken at chainages of multiples of 20 along the centerline of the road and also at BC, EC
and MC with the help of a level .Thus after performing the necessary calculations, the level
was transferred to all those points with respect to the R.L. of the given B.M. Then finally
the L-Section of the road was plotted on a graph paper on a vertical scale of 1:100 and a
horizontal scale of 1:1000.
10.6.8 CROSS SECTION
Cross sections at different points are drawn perpendicular to the longitudinal section of the
road on either side of its centerline in order to present the lateral outline of the ground.
Cross sections are also equally useful in determining the amount of cut and fill required for
the road construction. Cross sections were taken at chainages of multiples of 20 along the
centerline of the road and also at BC, EC and MC upto 15 m on both side of center line.
While doing so, the horizontal distances of the different points from the centerline were
measured with the help of a tape and the vertical heights with a measuring staff at points
where there was a sharp change in the elevation. The R.L. was transferred to all the points
by performing the necessary calculations and finally, the cross sections at different sections
were plotted on a graph paper on a scale of 1:100 both vertical and horizontal.
10.7Curve setting
Curves are generally used on highways and railways where it is necessary to change the
direction of the motion of the vehicle. A curve may be circular, parabolic or spiral and is always
tangential to the two straight directions commonly known as tangents.
Curves which are generally used on highways are as follows:
 Simple Circular Curve
 Transition Curve
 Vertical curve
1) SIMPLE CIRCULAR CURVE:
A simple circular curve is the one which consists of a single arc of a circle. It is tangential to
both of the straight lines namely tangents. During the road survey, it is always kept in mind

Page 45
that the radius of the simple circular curve should not be less than 12m. As far as possible,
flat circular curves are preferred to that of the sharp one. Flat curves are comfortable to the
passengers and there is less possibility of accident. Before setting out the curve, its elements
are essential to be computed. Some essential elements of simple circular curve are as
follows:
 Length of tangent: R tan (Δ/2)
Where,
R = radius of simple circular curve
Δ = deflection angle
 Length of long chord: 2R Sin (Δ/2)
 Apex distance: R (Sec(Δ/2) – 1)
 Mid ordinate: R (1 - Cos(Δ/2))
 Length of curve: ΠRΔ/180
 Chainage of T1: Chainage of IP - R tan (Δ/2)
 Chainage of T2: Chainage of T1 + ΠRΔ/180
Setting out of simple circular curve:
A simple circular curve can be set in the field by various linear and angular methods which are
listed as follows:
 Linear method: Linear method is defined as the method of setting curve in which only chain
or tape is used i.e. no angular instruments are used to set the curve. This method is preferable
where high accuracy is not required and the length of the curve to be set is short. Some
common linear methods of setting of the simple circular curve are as follows:
 By ordinates from the long chord
 By perpendicular offset from tangents
 By radial offset from tangents
 By offset from the chords produced
 By successive bisection of the curves

R R
O
D
C
BA
T1
IP
T2
Δ
Fig: Simple Circular
Curve

Page 46
 Angular method: Angular method is the one in which both angles and the distances are used
to set the curve in the field. Generally, tangential deflection angle and the distance are made
to be measured by Total Station. Some of the most common angular methods of setting out
of simple circular curve are as follows:
 Rankine’s method of tangential angles
 Two theodolite method
 Tacheometric method
2) TRANSITION CURVE
A transition curve is a curve of varying radius introduced between a straight and a
circular curve, or between two branches of a compound curve or reverse curve. The
functions of a transition curve are as follows:
 To accomplish gradually the transition from the tangent to the circular curve, so that the
curve is increased gradually from zero to a specified value.
 To provide a medium for the gradual introduction or change of the required super-
elevation.
A transition curve introduced between the tangent and the circular curve should fulfill the
following conditions:
i. It should be tangential to the straight.
ii. It should meet the circular curve tangentially.
iii. Its curvature should be zero at the origin on straight.
iv. Its curvature at the junction with the circular curve should be the same as that of the
circular curve.
v. The rate of increase of curvature along the transition should be the same as that of
increase of cant or super-elevation.
vi. Its length should be such that full cant or super-elevation is attained at the junction with
the circular curve.
The length of transition curve should be such that the required super-elevation or cant is
provided at a suitable rate. There are three methods for determining its length:
 By an Arbitrary Gradient

Page 47
 By the Tim Rate
 By the Rate of Change of Radial Acceleration
Elements of transition curve:
 Length of tangent = (R+S) tan Δ/2 + L/2
Where, R = Radius of simple circular curve joining transition curve
S = Shift
L = Length of the transition curve
 Shift (S) = L2/(24R)
 Spiral Angle (Δs) = 180L/2ΠR
 Central circular Angle (Δc) = (Δ -2Δs)
 Length of the circular curve = ΠR (Δ -2Δs)/180º
 Length of the combined curve = ΠR (Δ -2Δs)/180º + 2L
3) VERTICAL CURVE:
A vertical curve is used to join two intersecting grade lines of railroads, highways or
other routes to smooth out the changes in the vertical motion. An abrupt change in the rate of the
grade could otherwise subject a vehicle passing over it to an impact that would be either
injurious or dangerous. The vertical curve, thus, contributes to the safety, comfort and
appearance.
Super-elevation:
When a pavement or a track is sloped upwards the outside of the curve, it is termed as banked or
super elevated. Thus, ‘super-elevation or cant’ is the amount by which the outer end of the road
or outer rail is raised above the inner one.
Grade:
A grade which is expressed as percentage or 1 vertical is to n horizontal, is said to be upgrade or
positive grade when the elevation along the road alignment increases, while it is termed as
downward grade or negative grade when the elevation decreases along the direction of the
motion.
10.8 Structures:
The main structures provided for road constructions are retaining structures, cross drain, side-
drain, bio-engineering structures etc. retaining structures are provided where the slope is critical.
Gabion structure, dry masonry structures are the example
The camber of the road is made perfectly by putting 4% of stage for gravel road so as to avoid

Page 48
any collection of water on it.
The maximum gradient of the road is about 7% and 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. Longitudinal drain is provided on the sides of the road. Retaining
walls are provided on required places.
Construction of hill roads involves many special structures. These may include wide range of
structures which are used to retain soil mass, to increase stability of road embankment slopes as
well as natural hill slopes, to accommodate road bed in steep slope, to penetrate deep through
mountain pass and so on. Integration of bioengineering measures with engineering structures is
yet another sector requiring special attention. The following types of structures are used normally
on the hill road:
 Retaining structures
 Drainage structures
 Slope protection structures
Retaining structures:
A retaining structure is usually a wall constructed for the purpose of supporting or retaining a
vertical or nearly vertical earth bank, which in turn may support vertical loads along with the
self-weight of it. It provides adequate stability to the road way and to the slope. Retaining
walls are constructed on the valley side on the roadway and also on the cut hillside to prevent
slide towards the roadway. Types of retaining wall are:
1. Gravity walls
2. Semi gravity walls
3. Cantilever walls
4. Counter fort walls
5. Buttressed walls
6. Crib walls
7. Reinforced soil walls
10.9 Computation and Plotting
After the calculations of RL were completed, the L-section and X-section was plotted. In L-
section, appropriate formation level was set considering the specification. Then, the cutting and

Page 49
filling was done on X-section based on formation level. Drainages and retaining structures were
placed as per requirement. The plan of road corridor is also plotted in a scale of1:500.
10.10 Comments and Conclusions:
Survey of the road alignment was challengeable and tough due to up and downs in the road
alignment. A considerable amount of time was spent for figuring out the proper alignment of
road. Extra case is taken to avoid any soil erosion and any other ecological damage. We did our
best to come up with the safe, economical, short and easy route to connect the two specified
point. In addition, during our reccy, we encountered a considerable settlement which was needed
to be accessed by the road. So we make our initial alignment to turn through the settlement.
After performing this road alignment survey, we were able to build confidence in designing
roads at difficult terrain taking factors like economy, convenience and its use into consideration

Page 50
The facilities and the guidance provided at the survey camp were good. We felt that the time for
the topographical detail was quite limited and would like to suggest for better adjustment in the
future. The orientation part of surveying should be enforced in a way that it forms an integral
part of surveying at the site not just as a field practice. The time should be allocated in such a
manner that every event of surveying gets limited amount of time, so that they can be done with
greater accuracy and more knowledge can be gained from those events. As many students were
facing problem to fetch bus due to late night hours, it would have been better if we reduced
working hours by increasing working days.
The most important thing that we would like to suggest that the survey camp should not
only be done for report submission, but it should be stressed for gaining more and more
knowledge.
11. RECOMMENDATION

Page 51
With the helpful regard of teacher and cooperative behavior of all friends, all the work was
completed as scheduled in routine time assigned to us although we faced minor difficulties due
to extreme temperature during our work .All results we obtained were within the limits given to
us. The camp really helped us with the practical parts of survey fieldwork as we were working in
conditions we will surely have to face in future. It increased our confidence in handling
instruments as well as completing projects within given deadline. This trip also offered us relief
from the monotony of performing all survey practical within the college compound. It was also a
chance to get to know our friends from other sections work closely and interact with them. This
trip is a good experience in dealing with locals and other people who were interested in our
work. We think HCOE should organize such trips frequently and for all possible subjects, as
practical knowledge is better .In these trips, we gain first hand concept of the subject matter that
makes it easier for us to grasp the concept .All in this entire trip was very informative, effective
and enjoyable.
Any suggestion and comment are heartly acceptable. During report preparation all
confusion are cleared by teachers to whom we are very grateful.
12. CONCLUSION

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1. “SURVEYING” (Vol. I & II)” - Punmia, B. C.; Khanna Publishers India.
2. “A TEXT BOOK OF SURVEYING”-R.Agor
3. “NEPAL ROAD STANDARDS”- Published by His Majesty’s Government, Department
of Roads Nepal.
4. Various class notes and photocopies, provided by the teachers
5. Data recording sheet/file provided by survey committee 2073
6. www.autodesk.com
7. www.cadtutor.com
8. www.mapsgoogle.com.np
9. www.earth.google.com
13. BIBLIOGRAPHY

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