basicsofsurveying

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URE 110 - Fundamentals of Surveying

asics of Surveying

BASICS OF

SURVEYING

Robert Burtch

Surveying Engineering Department

Ferris State University

DEFINITION

The art and science of making suchmeasurements as are necessary todetermine the relative position of pointsabove, on, or beneath the surface of theearth, or to establish such points in aspecified position

Surveyor needs understanding of

rigorous mathematical to analyze andadjust

scientific principles underlying andaffecting measurements


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asics of Surveying

BRANCHES OF SURVEYING

Geodetic Surveying

Branch of surveying

in which account is

taken of figure andsize of earth

Plane Surveying

Branch of surveying

in which the surface

of the earth isconsidered a plane

surface

PHASES OF SURVEYING

Field Work

Data procurement phase

Office Work data are

Analyzed

Reduced to useful form by mathematical

calculationsAdjusted

Frequently converted to graphical mode of

expression


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asics of Surveying

KINDS OF SURVEYS

Property surveys Determine boundary lines, location of

property corners, acquisition of data toprepare land subdivisions

Route surveys

Designing and constructing engineeringprojects associated with transportation andcommunications

Industrial surveys

Surveys in aircraft and other industries

where accurate dimensional layoutsnecessary

KINDS OF SURVEYS

Topographic surveys

Collect field data to prepare topographicmaps

Hydrographic surveys

Map shorelines of water bodies, chartbottom areas of streams, lakes, harbors,etc., measure flow of rivers, assess otherissues related to navigation and waterresources

Aerial surveys (photogrammetry)

Use photographs mounted in speciallydesigned planes


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asics of Surveying

KINDS OF SURVEYS

Mine surveys Determine position of underground works

and surface mines, fix position anddirection of tunnels and shafts, definesurface boundaries

Construction surveys

Performed during building of structure orproject to fix elevations, horizontal position,and dimensions

Control surveys

Provide basic horizontal and verticalposition data for engineering mission

KINDS OF SURVEYS

Final (As Built) survey

Tie in features that have just been

constructed to provide final record of

construction and to check that construction

has proceeded according to design plan


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asics of Surveying

BASIC SURVEY

MEASUREMENTS: DEFINITIONS

Direction of gravity used as

reference direction

Vertical means direction of gravity

Horizontal means direction

perpendicular to gravity

SURVEY GEOGRAPHIC

REFERENCE Latitude () Lines run east-west

parallel to equator

Max angle 90

South latitudesnegative

Longitude () Lines run north south,

converge at poles

0 - Greenwich

Measured east andwest - 180 max angle

West longitudenegative


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asics of Surveying

DEFINITIONS Oblate Spheroid

Ellipsoid of

Revolution Solid obtained by

rotating an ellipse onits shorter axis

Idealized figure of

earth

DEFINITIONS Level surface (geoid)

Continuous surface that is at all pointsperpendicular to the direction of gravity

Can be thought of as the surface of largebody of water at complete rest (unaffectedby tides, etc.)

Elevation

Vertical distance above or below a givenreference level surface

Difference in elevation

Vertical distance between two levelsurfaces containing the two points


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asics of Surveying

DEFINITIONS Vertical line

Line following direction

of gravity Vertical line passing

through several different

points on surface of

earth do not intersect ata common point

Vertical lines not

necessarily normal tosurface of the earth

Deflection of vertical

Angle between

perpendicular to geoidand ellipsoid

DEFINITIONS

Horizontal line

Line perpendicular to vertical line at a point

Horizontal plane

Plane perpendicular to vertical line at point

Only 1 horizontal plane through a given

point

Vertical plane Plane containing vertical line at the point

Infinite number of vertical planes as a

given point


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DIRECTION

Azimuth- clockwise

angle from north to

line

Bearing angle

measured from north

or south to east or

west

ACCURACY & PRECISION

Accuracy

closeness between

measurement and

true value

Precision

closeness to one

another of a set ofrepeated

observations


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asics of Surveying

ERRORS

No measurement free of error (except

counting)

Mistakes or blunders

Not really errors because they are usually

so gross in magnitude

Most common reason carelessness

Must be discovered and eliminated

ERRORS

Systematic error

Occur according to a system which can be

expressed mathematically

Magnitude and sign can be determined

Follow definite pattern

Can be caused by observer, instrument,

environment

Random error

Error left after systematic error removed

May tend to cancel themselves


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asics of Surveying

UNITS OF LENGTH

Imperial units

(feet)

Usually

subdivided into

decimal units insurveying

Use of inches

SI units (meters)

Le Systeme

Internationale dUnites

(International Systemof Units

Normally subdivided

into decimeter,

centimeter, millimeter

NORMAL PREFIXES FOR

METER

exa (E) 1018

peta (p) 1015

tera (t) 1012

giga (g) 109

mega (m) 106

kilo (k) 103

hecto (h) 10

2

deka (da) 101

Ex: kilometer = 1,000m

deci (d) 10-1

centi (c) 10-2

milli (m) 10-3

micro ()10-6

nana (n) 10-9

pico (p) 10-12

femto (f) 10-15

atto (a) 10-18

Ex: millimeter = 0.001m


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METRIC SYSTEM

1791 French Academy of Sciencesrecommended metre to be1/10,000,000th part of polar quadrantpassing through Paris

1799 Academy of Sciences developednew standard Metre of the Archives made of platinum 1 meter in length

1999 General Conference of Weightsand Measures adopts International

Prototype Metre platinum & iridiumbar

METRIC SYSTEM

1960 National Prototype Meter

1,650,763.73 wavelengths of Krypton 86

atom in a vacuum

1983 Conference Generale des Poids et

Mesures redefined meter as length of

the path traveled by light in a vacuumduring a time interval of 1/299792458 of

a second


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FEET-METER CONVERSION


Ferdinand Hassler brought iron meter

bar to U.S. in 1805 for work with Coast

Survey

1866 Congress legalized use of metric

system

1893 Mendenhall Order

Superintendent of Weight & Measures

1 meter = 39.37 inches (exact)

1 U.S. Yard = (3600/3927) meter (exact)


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1959 U.S. & U.K. agreed that Imperialunits used in both countries should be

the same

Defined 1 Yard = 0.9144 metre (exact)

1 ft = 0.3048 m (exact)

1 inch = 25.4 mm (exact)

Did not change relationship established by

Congress kept for surveying and called

U.S. Survey foot

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