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SURVEYING

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Title: SURVEYING


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SURVEYING I (CE- 128)
COURSEPACK FOR UG
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SURVEYING I (CE- 128)
  • OBJECTIVES
  • COURSE OUTLINE
  • DETAILED SYLLABUS
  • LESSON PLAN

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SURVEYING I (CE- 128)
OBJECTIVES
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SURVEYING I (CE- 128)
OBJECTIVES
  • To enable students to understand theory and
    practical of surveying
  • To develop skills to use the modern survey
    instruments

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SURVEYING I (CE- 128)
COURSE OUTLINE
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SURVEYING I (CE- 128)
COURSE OUTLINE
  • COURSE TITLE SURVEYING I
  • COURSECODE CE 128
  • CREDIT HRS 3 THEORY 2 PRAC
    1
  • NO. OF WEEKS 18
  • INSTRUCTOR ENGR MUHAMMAD AMMAR

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SURVEYING I (CE- 128)
SCHEDULE
  • WEEK 01 General Introduction to Survey (Lec
    1)
  • WEEK 02 Distance Measurement Chain/Compass
    Surveying (Lec 2)
  • WEEK 03 Plane Table Surveying (Lec 3)
  • WEEK 04 Traversing (Lec 4)
  • WEEK 05 Traversing (Lec 5)
  • WEEK 06 Traversing (Lec 6)

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SURVEYING I (CE- 128)
  • WEEK 07 Leveling (Lec 7)
  • WEEK 08 Leveling (Lec 8)
  • WEEK 09 Leveling (Lec 9)
  • WEEK 10 Contouring (Lec 10)
  • WEEK 11 Contouring (Lec 11)
  • WEEK 12 Computation of Areas (Lec 12)
  • WEEK 13 Computation of Volumes (Lec 13)

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SURVEYING I (CE- 128)
  • WEEK 14 Modern Instruments in Survey (Lec
    14)
  • WEEK 15 Modern Instruments in Survey (Lec
    15)
  • WEEK 16 Practical Survey Training (SURVEY
    WEEK)

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SURVEYING I (CE- 128)
  • DISTRIBUTION OF MARKS
  • THEORY
  • 4 x Quiz 15 Marks
  • 2 x Assignment 05 Marks
  • 2 x One Hour Test (OHT) 30
    Marks
  • 1 x Final Exam 50
    Marks
  • PRACTICAL
  • Practical Work/Projects 60 Marks
  • Final (Viva) 30 Marks
  • Performance in field work/attendance 10 Marks

Details will be conveyed to you before the
start of survey week
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SURVEYING I (CE- 128)
  • RECOMMENDED BOOKS
  • Surveying Principles and Applications by
    Kavanagh
  • Surveying and Leveling Vol. 1 by Kanetkar
  • Surveying for Construction by Irvine (Reference
    Book)
  • Surveying Theory and Practice by Davis McGraw
    Hill (Reference Book)

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SURVEYING I (CE- 128)
DETAILED SYLLABUS
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SURVEYING I (CE- 128)
DETAILED SYLLABUS
  1. GENERAL INTRODUCTION Definition of survey,
    principle of survey, types of survey,
    classification of survey, instruments used in
    survey, precision and accuracy, accuracy ratio,
    scale and its construction, distance measurement
    and use of instrument for distance measurement,
    errors, distance measured by tape and errors
    involved, methods of chain surveying and errors
    involved.
  2. PLANE TABLE SURVEYING Part and accessories of
    plane table, setting and orientation, methods of
    plane tabling.
  3. TRAVERSING Methods of traversing, bearings and
    calculation of angles from bearings, traversing
    with chain and compass.

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  • LEVELING Definitions, types of levels, Staff,
    principles of leveling, reduction of levels,
    profile leveling, curvature, refraction, effect
    of curvature and refraction, corrections,
    barometric leveling, hypsometry, errors in
    leveling.
  • CONTOURING Definitions, characteristics uses,
    locating contours, interpolation of contours,
    setting grade stake for sewers.
  • COMPUTATION OF AREAS introduction, determination
    of areas, computation of areas from plans,
    trapezoidal rule, simpson rule

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  1. COMPUTATION OF VOLUMES measurement of volumes
    from cross-sections and various formulas for
    computation of volumes, determination of capacity
    of reservoir.
  2. MODERN METHODS IN SURVEYING principles of EDMI,
    EMD characteristics, total station, Global
    Position System.

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LESSON PLAN
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  • LECTURE 01 INTRODUCTION TO SURVEY
  • Definition - Surveying is the art of making
    such measurements as will determine the relative
    positions of distinctive features on the surface
    of the earth in order that the shape and extent
    of any portion of earths surface may be
    ascertained and delineated on a map or plan. It
    is essentially a process of determining positions
    of points in a horizontal plane. ORSurveying is
    the art and science of measuring distances,
    angles positions, on or near the surface of the
    earth. Leveling is art of determining the
    position of point in vertical plane.
  • Object of Survey -
  • The primary object of surveying is the
    preparation of a plan or map.
  • A plan is therefore, the projected representation
    to some scale, of the ground and the object on
    the horizontal plane which is represented by the
    plane of the paper on which the plan is drawn.
    The representation is called a map, if the scale
    is small, while it is called a plan, if the scale
    is large, e.g. a map of UK, a plan of a building.
  • The science of surveying has been developing
    from the very initial stage of human civilization
    according to his requirement. Earliest surveys
    were performed only for the purpose of
    demarcating its boundaries of plots of land.

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  • Due to advancement in technology, the science of
    surveying has also attained its due importance.
    In the absence of accurate maps, it is impossible
    to lay out the alignments of roads, railways,
    canals, tunnels, transmission power lines,
    microwave or television relaying towers.
  • Detailed map of the sites of engineering projects
    are necessary, therefore, surveying is the first
    step in the execution of any project
  • Types of Surveys- (1) Plane Surveying and (2)
    Geodetic Surveying
  • Plane surveying In plane surveying the curvature
    of the earth is not taken into account, as the
    surveys extend over small areas. In dealing with
    plane surveys, the knowledge of plane geometry
    trigonometry is only required. Surveys covering
    an area up to 260 sq. km may be treated as plane
    surveys because the difference in length between
    the arc the subtended chord on the earth
    surface for a distance of 18.2km is only 0.1m.
  • Scope Use of Plane Surveying Plane Surveys are
    carried out for engineering projects on
    sufficiently large scale. They are used for the
    layout of highways, railways, canals, fixing
    boundary pillars, construction of bridges etc.
    For majority of engineering projects, plane
    surveying is the first step to execute them.

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  • Geodetic Surveying The surveys in which
    curvature of the earth is taken into account
    higher degree of accuracy in linear as well as
    angular observations is achieved are known as
    Geodetic Surveying. As the surveys extend over
    large areas, lines connecting any two points are
    on the surface of the earth are treated as arcs.
    A knowledge of spherical trigonometry is
    necessary for making measurements for the
    geodetic surveys.
  • Scope Use of Geodetic Surveying Geodetic
    Surveys are conducted with highest degree of
    accuracy to provide widely spaced control points
    on the earths surface for subsequent plane
    surveys. In Pakistan, Geodetic Surveys are
    usually carried out by the survey of Pakistan.
  • Classification Surveys may be classified in a
    variety of ways
  • a. Classification based upon the nature of the
    field of survey
  • (1) Land Surveys.
  • (2) Hydrographic Surveys.
  • (3) Astronomical Surveys.
  • b. Classification based upon the object of
    survey
  • (1) Archaeological Surveys for unearthing relics
    of antiquity
  • (2) Geological Surveys for determining
    different strata in the earths crust.

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(3) Mine Surveys for exploring mineral wealth
such as gold, coal, etc. (4) Military Surveys
for determining points for strategic importance
both offensive and defensive. (5) Engineering
Surveys for determination of quantities for
designing engineering works. c.
Classification based upon the methods employed in
survey (1) Triangulation Surveys. (2)
Traverse Surveys. d. Classification based upon
the instrument employed (1) Chain
Surveys. (2) Theodolite Surveys. (3) Tachometric
Surveys. (4) Compass Surveys (5) Plane Table
Surveys. (6) Photogrammetric Surveys.
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6. Land surveys may be further sub-divided into
the following classes (a) Topographical
Surveys for determining the natural features of a
country such as hills, valleys. Rivers, nallas,
takes, woods, towns, villages etc. (b) Cadastral
surveys in which additional details such as
boundaries of fields, houses and other
properties, path ways, are determined. (c) City
Surveys for laying out plots and constructing
streets, water supply systems, and
sewers. 7. Engineering Surveys may be further
sub-divided into (i) Reconnaissance surveys
for determining the feasibility and rough cost of
the scheme. (ii) Preliminary surveys for
collecting more precise data to choose the best
location for the work and to estimate the exact
quantities and costs (iii) Location surveys for
setting out the work on the ground. 8.
Principles of Surveying - The two fundamental
principles upon which various survey methods are
based are
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1. To work from the whole to the part The
main principle of surveying is to work from the
whole to the part. To achieve this in actual
practice, a sufficient number of primary control
points are established with higher precision in
around the area to be detail surveyed. Minor
control points in between the primary control
points are then established with less precise
method. Further details are surveyed with the
help of these minor control points by adopting
any one of the survey methods. The main idea of
working from the whole to the part is to prevent
accumulation of error to localize minor errors
within the framework of the control points. On
the other hand, if survey is carried from the
part to the whole, the errors would expand to
greater magnitudes the scale of the survey will
be distorted beyond control. 2. Location of
a point by measurement from two control points
The control points are selected in the area the
distance between them is measured accurately. The
line is then plotted to a convenient scale on a
drawing sheet. The location of the required point
may then be plotted by making two measurements
from the given control points as follow Let A
B be two given control points. Any other point,
say D can be located with reference to these
points, by any one of the following method
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  • Rectangular coordinates by the perpendicular dD
    and the distance Ad. The distance Bd may be
    measured instead of Ad (fig--)
  • Trilateration by the two distances AD and BD
    (fig--)
  • Polar coordinates the angle BAD measured at A
    and the distance AD. Instead, by angle DBA
    measured at B and the distance BD (fig--)
  • Triangulation by the two angles BAD and ABD
    measured at A and B (fig---)

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  • Scales - The scale of a map or plan is the fixed
    proportion which every distance between the
    locations of the points on the map or plan bears
    to the corresponding distance between their
    positions on the ground. Thus if 1 cm on the map
    represents 10 m on the ground, the scale of the
    map is 10 m to 1 cm often written simply as 1 cm
    10m. The scale is also expressed by means of a
    regular fraction whose numerator is invariably
    unity. The fraction is called Representative
    Fraction (R.F).For example, if the scale is 10m
    to 1cm, the R.F. of the scale is 1cm / 10
    100cm 1/1000 Scales of the maps are
    represented by the following two methodsa).
    NUMERICAL SCALESb). GRAPHICAL SCALES
  • Characteristics of a Scale Line -
  • a. It should be sufficiently long. (Usually
    between 18 cm to 27 cm but not more than 32 cm)
  • b. It should be accurately divided and carefully
    numbered.
  • c. The zero must always be placed between the
    unit and its subdivisions.
  • d. The name of the scale together with its
    representative fraction should be written on the
    plan.
  • e. It should be easily read and should not
    involve any arithmetic calculation in measuring
    distance on the map. The main divisions should,
    therefore, represent one, ten, or hundred units.

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  • Plain Scale On a plain scale it is
    possible to read only two dimensions such as
    meters and decimeters, units and tenths etc.
  • Example Draw a scale 1cm 4m to read
    to a meter and show on it 47m. Const
    Draw a line 20 cm long and divide it into eight
    equal parts. Subdivide the first division from
    the left into 10 equal parts each subdivision
    reading 1 meter. Place the zero between the
    subdivided part and the undivided part and mark
    the figures counting from zero in both dir. To
    read 47m place one leg of the dividers at 40 and
    the other at 7.
  • Stages of Survey Operations The entire work of
    a survey operation may be divided into three
    distinct stages 1. Field work-Reconnaissance,
    Observations, Field Records 2. Office
    work-Drafting, Computing, Designing 3. Care
    adjustment of the instruments
  • Accuracy Of Surveyed Quantities
  • Surveyors primary objective is to achieve
    accuracy in their measurements.
  • Survey is of little value if it is not accurate.
  • In surveying, the most common task is to find the
    3D positions of a series of

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points, the x, y z coordinates. Physical
measurements are therefore required in the form
of linear, angular height dimensions. There
will be error in these quantities which must be
eliminated, discounted or distributed. a).
Classification of ErrorsGross They are simply
mistakes. They arise mainly due to the
inexperience, ignorance or carelessness of the
surveyor. These errors cannot be accommodated
observations have to be repeated. Examples
reading the tape wrongly, recording a wrong
dimension when booking, turning the wrong screw
on an instrument. Systematic These are errors
which arise unavoidably in surveying follow
some fixed law. Their sources are well known. A
simple example is illustrated by the temp error
in tape measurements. A tape is only correct at a
certain standard temp therefore if the ambient
temp on a certain day is higher or lower than
standard, the tape will expand or contract
cause an error which will be the same no matter
how often the line is measured.
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SURVEYING I (CE- 128)
Constant These are errors which do not vary at
any time, in other words, they have the same
sign, either positive or negative. As an
illustration, consider the nature of the
dimensions required for plotting on maps plans.
These must be horizontal if no attention is
paid to the slope of the ground when making a
measurement, the dimension so obtained will be
too long. No matter how often the measurement is
made or how many other slopes are measured, the
results will always be too long. Likewise, if a
tape has stretched through continuous use, any
resultant measurements will always be too
short. Constant errors are well known
appropriate corrections are applied to obtain the
correct result.Accidental/Random These are the
small errors which inevitably remain after the
others have been eliminated. There are three main
causes Imperfections of human sight touch
(human errors), Imperfections of the instruments
being used at the time Changing atmospheric
conditions. A good example arises in the
measurement of an angle using an instrument
called a theodolite.
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b). Accuracy Precision Accuracy Precision
are not synonymous. The difference is illustrated
in the following example A line of survey is
measured six times all six measurements lie
within an error band of 2mm. However, the tape
when checked, is found to have stretched by 10mm
through continuous use. The results of the six
measurements are precise in that they have little
scatter but they are not accurate because each is
in error by 10mm. In surveying, accuracy is
defined by specifying the limits between which
the error of a measured quantity may lie, for
example, the accuracy of the measured building
might be (20.54 0.01) metres.Accuracy Ratio
The accuracy ratio of a measurement or series of
measurements is the ratio of error of closure to
the distance measured. The error of closure is
the difference between the measured location
the theoretically correct location. To
illustrate, a distance was measured found to be
250.56 ft. The distance was previously known to
be 250.50 ft. The error is 0.06 ft in a distance
of 250.50 ft.
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accuracy ratio 0.06/250.50 1/4175
1/4200The accuracy ratio is expressed as a
fraction whose numerator is unity whose
denominator is rounded to the closest 100
units.
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  • LECTURE DISTANCE MEASUREMENT
  • Two main methods of determining the distances
    between points on the surface of the earth.
  • Direct Measurement distances are actually
    measured on the surface of the earth by means of
    chains, tapes etc.
  • Computative Measurement Distances are
    determined by calculations indirectly by using
    the field data as in triangulation, tacheometry
    etc.
  • Instruments for Measuring Distances 1).
    Chain-Gunters Chain (66ft), Engineers
    Chain(100ft), Metric Chain(20/30m) 2). Steel
    Band 3). Tapes-Cloth/Linen Tape, Metallic Tape,
    Steel Tape, Invar Tape
  • Arrows/Chain Pins 10 arrows generally accompany
    a chain, used to mark the end of each chain
    during the process of chaining.

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  • Instruments for Marking Stations 1).
    Pegs 3). Ranging Poles 5). Plumb Bobs 2).
    Ranging Rods 4). Offset Rod
  • Ranging a Line The process of marking a number
    of intermediate points on a survey line joining
    two stations in the field so that the length
    between them may be measured correctly, is known
    as ranging. Ranging may be classified as DIRECT
    RANGING INDIRECT RANGING
  • Direct Ranging When intermediate ranging rods
    are placed along the chain line, by direct
    observation from either end station, the process
    is known as direct ranging.
  • Line Ranger It is a small reflecting instrument
    used for fixing intermediate points on a chain
    line.
  • Indirect Ranging When end stations are not
    intervisible the intermediate ranging rods are
    placed in line by interpolation or by reciprocal
    ranging or by running an auxiliary line (or
    random line), the process is known as Indirect
    Ranging.

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  • Degree of Accuracy in Chaining For comparison
    of precision of chaining when line of different
    lengths are measured under dissimilar conditions,
    it is the usual practice to express the error as
    ratio (1n), which is called the chaining ratio.
    It is the ratio of the error to the distance
    measured. EXAMPLE 1/1500, 1/5000 etc. By this
    is meant an error of 1 unit in 1500 units, or an
    error of 1 unit in 5000 units The limits of
    errors under different conditions are as
    follows 1). For ordinary measurements with a
    steel band on flat ground with careful work 1
    in 2000. 2). For ordinary measurements with a
    carefully tested chain on fairly level ground
    with reasonable care 1 in 1000. 3). Under
    average conditions 1 in 500. 4). For
    measurements over rough or somewhat hilly ground
    1 in 250.
  • Error in Measurement due to Incorrect Chain
    Length If the chain is too long, the measured
    distance will be less if the chain is too
    short, the measured distance will be more. a.
    The true length of line L / L x measured
    length of line
  • Where L the incorrect length of a chain or
    tape
  • And L the true length of a chain or tape

Note Use plus sign when the chain is too long
and minus sign when it is too short
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SURVEYING I (CE- 128)
  • b. The true area of a plot of a land (L/L)2 x
    Measured area of the plot c. The true volume
    of an excavation (L/L)3 x Measured volume of
    the excavation
  • Examples on Correction of Distance and Area1.
    The length of a line measured with a 20 m chain
    was found to be 634.4 m. It was afterwards found
    that the chain was 0.05 m too long. Find the true
    length of the line.
  • Solution True length of line L/L x measured
    length of line.
  • L 20.05 m.
  • L 20 m.
  • Measured length 634.4 m.
  • Therefore, True length of the line 20.05/20x
    634.4
  • 635.00 m.

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2. The length of a line measured by means of a 20
m chain was found to be 610.2 m known to be 612.0
m. What was the actual length of the
chain?SolutionSince the measured length of the
line is less than its true length, the chain was
too long. Now true length of the line L/L x
measured length. True length of the line 612.0
m. Measured length of the line 610.2 m.
L 20.0 m. . 612.0 L/20.0 x
610.2 . L 612.0x20.0/610.220.066 m.
3. A 20 m chain was found to be 0.05 m too long
after chaining 1400 m. It was found to be 0.1 m
too long after chaining 2200 m. If the chain was
correct before commencement of the work find the
true distance. Solutiona. Since the chain was
correct i.e. 20 m long at the beginning and was
20.05 m long after chaining 1400 m, the increase
in length was gradual. . Mean elongation
00.05/20.025 m. . True distance 20.025/20 x
1400 1401.75m.
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  • b. The remaining distance (2200-1400) 800 m was
    measured with the same chain. If was 0.05 m too
    long at the commencement of chaining and 0.10 m
    too long at the end of chaining.
  • . Mean elongation 0.050.10/2 0.075 m.
  • True distance 20.075/20 x 800 803.00m.
  • where, total true distance 1401.75 803.00 m.
  • 2204.75 m.
  • CHAINING ON SLOPING GROUNDS 1). Chaining on
    the surface of a sloping ground gives the
    sloping distance. 2). For plotting the surveys,
    horizontal distances are required. 3). It is
    therefore, necessary either to reduce the sloping
    distances to horizontal equivalents or to measure
    the horizontal distances between the stations
    directly. 4).Two methods for getting the
    horizontal distance between two stations on a
    sloping ground DIRECT METHOD INDIRECT METHOD

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Fig. DIRECT METHOD Horizontal distances are
measured on the ground in short horizontal
lengths. Also known as Stepping Method.
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Fig. INDIRECT METHOD Measuring the slope angle
with a CLINOMETER
Fig. INDIRECT METHOD Measuring the slope angle
from Difference in Elevations
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Fig. INDIRECT METHOD Hypotenusal Allowance
Correction Method
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  • ERRORS IN CHAINING 1). Cumulative Errors 2).
    Compensative Errors
  • CUMULATIVE ERRORS The errors which occur in the
    same direction tend to accumulate, or to add up
    are called Cumulative Errors. Such errors make
    the apparent measurements always either too long
    or too short.a). Positive Cumulative Errors
    Those errors which make the measured lengths more
    than the actuals are known as positive cumulative
    errors. These are caused in the following
    situations i). The length of the chain or tape
    is shorter than its standard length. ii). The
    slope correction ignored while measuring along
    the sloping ground. iii). The sag correction, if
    not applied, when the chain or tape is suspended
    at its ends. iv). Due to incorrect
    alignment. v). Due to working in windy
    weather.

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  • b). Negative Cumulative Errors The errors which
    make the measured lengths less than the actuals
    are known as negative cumulative errors. These
    are caused in the following situations i).
    The length of the chain or tape is greater than
    its standard length.
  • COMPENSATING ERRORS The errors which are liable
    to occur in either direction tend to compensate
    are called compensating errors. These are caused
    in the following situations i). Incorrect
    holding of the chain ii). The chain is not
    uniformly calibrated throughout its length iii).
    Refinement is not made in plumbing during
    stepping method
  • COMMON MISTAKES IN CHAINING i). Displacement
    of the arrows ii). Failure to observe the zero
    point of the tape iii). Adding or omitting a
    full chain length iv). Reading from the wrong
    end of the chain v). Reading numbers wrongly/
    Reading wrong meter marks vi). Wrong
    recording in the field book viii). Calling
    numbers wrongly

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  • CORRECTIONS FOR LINEAR MEASUREMENTS i).
    Correction for standard length ii).

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