SURVEYING

Surveying

Surveying

is the art of determining the positions of the points on or near the earth’s surface by means of measurements

in the three elements of space; namely, distance, direction, and elevation

Surveying

is the art of measuring horizontal and vertical distances between objects, of measuring angles between lines,

of determining the direction of lines, and of establishing points by predetermined angular and linear measurements

Cadastral Surveys

are usually closed surveys which are undertaken in urban and rural locations for the purpose of

determining and defining property lines, boundaries, corners, and areas. These surveys are also made to fix the

boundaries of municipalities, towns, and provincial jurisdictions.

City Surveys

are surveys of the areas in and near city for the purpose of planning expansions or improvements, locating

property lines, fixing reference monuments, determining the physical features and configuration of the land, and

preparing maps.

Construction Surveys

these are surveys which are undertaken at a construction site to provide data regarding grades,

reference lines, dimensions, ground configuration, and the location and elevation of structures which are of concern to

engineers, architects, and builders

Forestry Surveys

a type of survey executed in connection with forest management and mensuration, and the

production and conservation of forest lands.

Hydrographic Surveys

refer to surveying streams, lakes, reservoirs, harbors, oceans, and other bodies of water. These surveys are made to map shore lines, chart the shape of areas underlying water surfaces, and measure the flow of stream

Industrial Surveys

sometimes known as optical tooling. It refers to the use of surveying techniques in ship building,

construction and assembly of aircraft, lay-out and installation of heavy and complex machinery, and in other industries

where very accurate dimensional layouts are required.

Mine Surveys

are surveys which are performed to determine the position of all underground excavations and surface

mine structures, to fix surface boundaries of mining claims, determine geological formations, to calculate excavated

volumes, and establish lines and grades for other related mining work

Photogrammetric Surveys

a type of survey which makes use of photographs taken with specially designed cameras

either from airplanes or ground stations. Measurements are obtained from the photographs which are used in

conjunction with limited ground surveys.

Route Surveys

involves the determination of alignment, grades, earthwork quantities, location of natural and artificial

objects in connection with the planning, design, and construction of highways, railroads, pipelines, canals, transmission

lines, and other linear projects.

Topographic Surveys

are those surveys made for determining the shape of the ground, and the location and elevation of natural and artificial features upon it. The features shown include such natural objects as hills, mountains, rivers, lakes, relief of the ground surface, etc; and works of man, such as roads, buildings, ports, towns, municipalities, and bridges.

Errors

defined as the difference between the true value and a measured value of a quantity. it is a deviation of an observation or a calculation from the true value and is often beyond the control of the one performing the operation.

Systematic Errors

Also called cumulative error. This type of error is one which will always have the same sign and magnitude as long as field conditions remain constant and unchanged. For changing field conditions there is a corresponding change in magnitude of error, however, the sign remains constant.

Accidental Errors

The occurrence of such errors are matters of chance as they are likely to

be positive or negative, and may tend in part to compensate or average out according to laws of probability. There is no

absolute way of determining or eliminating them since the error for an observation of a quantity is not likely to be the

same as for a second observation.

Accuracy

Indicates how close a given measurement is to the absolute or true value of the quantity measured. It implies the

closeness between related measurements and their expectations.

Precision

It refers to the degree of refinement and consistency with which any physical measurement is made. It is portrayed by the closeness to one another of a set of repeated measurements of a quantity.

Most Probable Value

It refers to a quantity which, based on available data, has more chances of being correct than has any other.

Pacing

consists of counting the number of steps or paces in a required distanc

Pace

is defined as the length of a step in walking

Breaking Tape

It is standard practice to hold the tape horizontally above the ground and to plumb at one or both ends when taping on sloping or uneven terrain surfaces. This requires the measurement of shorter distances which are accumulated to total a full tape length.

Slope Taping

This very practical method is generally preferred since measurements could be made quickly and more accurately than horizontal measurements

Correction due to sag

the difference between the arc formed by the tape and the subtending, and is always negative. In determining this correction, the arc is assumed to be a parabola, and is computed with sufficient precision by the formula.

Correction due to wind

This introduces an error to the measurement which is similar to the effect of sag but is usually much less

Normal Tension

is the amount of pull required to make the end points coincide with the marked points on the pavement.

Meridians

The direction of a line is usually defined by the horizontal angle it makes with a fixed reference line or direction.

True Meridian

also known as astronomic or geographic meridian. This line passes through the geographic north and south poles of the earth and the observer's position

Magnetic Meridian

a fixed line of reference which lies parallel with the magnetic lines of force of the earth. Its direction is defined by a freely suspended magnetic needle of a compass held at the observer's position.

Grid Meridian

a fixed line of reference parallel to the central meridian of a system of plane rectangular coordinates. One central meridian, which coincides with a true meridian, is usually selected and all other meridians are made parallel to this meridian

Assumed Meridians

an arbitrarily chosen fixed line of reference which is taken for convenience. This meridian is usually the direction from a survey station to an adjoining station or some well-defined and permanent point.

Degree

The sexagesimal system is used in which the circumference of a circle is divided into 360 parts or degrees. The angle of one degree is defined as the angle which requires 1/360 of the rotation needed to obtain one complete revolution

Grad

is the unit of measure in the centesimal system

Mil

It is commonly used in military operations as in fire direction of artillery units.

Radian

It is sometimes referred to as the natural unit of angle because there is no arbitrary number in its definition. It is used in computations such as determining the length of circular arcs and where high speed electronic digital computers are used

True North

north point of the true meridian. In maps and sketches, it is portrayed in the direction of the actual location of the earth’s north geographic pole and is always shown along a vertical line. It is symbolized by a star, an asterisk, or the letter TN.

Magnetic North

a north point that is established by means of a magnetized compass needle when there are no local attractions affecting it. At any point on the earth’s surface its direction is indicated by the direction of the magnetic lines of force passing through the point at a particular time. It may be Located either east or west of true north. The point is usually symbolized by a half arrowhead or the letter MN.

Grid North

a north point which is established by lines on a map which are parallel to a selected central meridian. It may coincide with lines directed towards true north. It may be symbolized by a full arrowhead or the letter GN or Y.

Assumed North

is used to portray the location of any arbitrarily chosen north point. It may be symbolized by a small blackened circle or the letter AN.

Interior Angles

The angle between adjacent lines in a closed polygon. These angles may be measured clockwise and counterclockwise.

Deflection Angles

The angle between a line and the prolongation of the preceding line. It may turn to the right (clockwise) or to the left (counterclockwise) and it is necessary to append the letters R or L to the numerical value to define the direction in which the angle has been turned. Right deflections (positive) are considered to have signs opposite to left deflections (negative).

Angles to the Right

are measured clockwise from the preceding line to the succeeding line.

Bearings

is the acute horizontal angle between the reference meridian and the line. A quadrantal system is used to specify bearings such that a line may fall under one of the following quadrants: NE, SE, NW, and SW

Forward Bearing

When the bearing of a line is observed in the direction in which the survey progresses

Back Bearing

if the bearing of the same line is observed in an opposite direction

Azimuths

The azimuth of a line is its direction as given by the angle between the meridian and the line measured in clockwise direction from either the north or south branch of the meridian.

P.F. = Taped Distance × Mean number of paces

Pace Factor Formula

s = √d² + h²

Slope formula

d = s cos (a)

what's the formula if the distance is missing and the the angle is given

Ct= k (T- Ts) L

Due to Temperature

Cs = w²L³/24P²

Due to Sag (per tape length)

Cs = W²L / 24P³

Due to Sag (whole tape length)

Cp = (P-Po) L / AE

Due to Tension and Pull

11.6×10^-6

Value of Therma Expansion

2.10x10^6 or 2.0×10^6

Modulus of Elasticity

cm³

What's the unit of cross sectional area?

Surveyor

is a professional person with the academic

qualifications and technical expertise to conduct one, or more,

of the following activities;

✓ to determine, measure and represent the land, three-

dimensional objects, point-fields, and trajectories

✓ to assemble and interpret land and geographically related information

Plane Surveying

uses normal instrument like chains, measuring tape, theodolite.

Geodetic Surveying

Use more precise instruments a d modern technology and carried area more than. 250 sq km

Planimetric Map

It is a representation of the

earth’s surface in the two

dimensions only

Topographic Map

it is a representation of the

earth’s surface in three

dimensions.

Photo map

are reproduction of an aerial

photograph or mosaic on which

grid lines, contours, boundaries,

place, names, and marginal

information have been added

or overprinted.

Instrument

Are the tools or devices which are used to carry out various jobs in

a field.

Astrolabe

It

had a metal circle with a pointer hinged

at its center and held by a ring at the

top, and a cross staff, a wooden rod

about 1.25 meters long with an

adjustable cross arm at right angles to it.

Telescope

Galileo designed a refracting telesc

to determine astronomical observations.

Semicircumferentor

➢ it was used to measure and lay off

angles, and establish lines of sight by

employing peep sights. It consists of a

semicircular limb divided into 180

degrees and sometimes subdivided into

minutes.

Transit

Also known as Universal Surveying Instrument invented by Young and Drapper. It is an optical l instrument that is mounted on a tripod that is commonly used in surveying and building

Plane Table

one of the oldest types of surveying instruments used in field mapping. It consists of a board attached to a tripod, in such a way that it be leveled or rotated to any desired directions.

Vernier

it is a short auxiliary scale placed

alongside the graduated scale of

an instrument, by means of which

fractional parts of the least or

smallest division of the main scale

can be determined precisely

without having to interpolate

Perambulator

Also known as surveyor’s

wheel. It used primarily for lower

accuracy surveys and are often

used by road maintenance or

underground utility workers and by

farmers for fast measures over

distances.

Compass

it is used for determining the

direction of lines and in calculating

angles between lines. It is also first

introduced for uses in navigation. It

consists of a magnetized steel

needle mounted on a pivot at the

center of a graduated circle.

Sextant

it is an instrument for determining

the angle between the horizon and

a celestial body such as the sun,

the moon, or a star, used in celestial

navigation to determine latitude

and longitude.

Measuring Tape

are used in surveying to

measure horizontal, vertical, and

slope distances

Electronic Distance Measurement

it is a surveying instrument used for measuring

distance electronically between two points

through electromagnetic waves.

Auto Level / Dumpy Level

it is widely used in surveying and

construction to measure height

differences and to transfer,

measure, and set heights of known

objects or marks.

Theodolite

it is an instrument that can measure

both horizontal and vertical angles,

which allows surveyors to

“triangulate” the position of objects

in a specific area

Total Station

it is an optical instrument commonly

used in construction, surveying and

civil engineering. It is useful for

measuring horizontal angles, vertical

angles and distances.

Real Time Kinematic

it is a highly accurate technique used to

determine the position of a receiver using the signal received from satellite-based positioning systems like GPS (USA

Unmanned Aerial Vehicle

commonly known as drone

Chief of Party

✓ Responsible for the overall direction, supervision, and operational control of the survey party.

✓ Responsible for its logistical and technical requirements, and problems of a field survey operatio

Assistant Chief Of Party

✓ Assist the chief of party in the accomplishment of the task assigned to the survey party.

✓ Takes over the duties of the chief of party during the absence of the chief.

Instrumentman

✓ Set up, level and operate surveying instruments such as the transit, engineer’s level, theodolite, sextant, plane table, alidade, and etc.

✓ Assist the technician in the operation of electronic surveying equipment

Technician

✓ Responsible for us and operation of all electronic instruments required in a field work operation.

✓ See to it that this equipment is functioning properly, are regularly calibrated, and are in proper adjustment.

Computer

✓ Perform all computations of survey data and works out necessary computational checks required in a field work operations

Recorder

✓ Keep a record of all sketches, drawings, measurements and observation taken or needed for a field work operation.

✓ Keeps table of schedules of all phases of work and the employment of the members of the survey party.

Head Tapeman

-, Responsible for the accuracy and speed of all linear measurements with the tape. Determines and directs the marking of stations to be

occupied by the surveying instruments and directs

the clearing out of obstructions along the line of sight.

Rear Tape Man

His duty is to assist the head tape man during taping operations and in other related work.

Flagman

His duty is to hold the flagpole or range pole at selected points as directed by the instrument man.

Rodman

Hold the stadia or leveling rod when sights are to be taken on it.

Axe Man/ Lineman

Clear the line of sight of trees, brush, and other obstructions in wooden country.

Responsible for the security and safety of the members of the survey party at the survey site.

Aid man

Render first aid treatment to members of the survey party who are involved in snake and insect’s bites, accidents, and other cases involving their health, safety and well-being.

Uitility Man

Render other forms of assistance needed by the survey party or as directed by the chief of party.

✓ Can be designated as driver.

✓ Responsible for the handling and transporting of surveying equipment, accessories, and supplies