types of equipment in surveying

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying20 min read

Introduction To Chain Surveying

Chain surveying is the branch of surveying in which simply linear measurements are made in the field. This is desirable for the survey of small areas with simple details and a relatively flat area.

It derives its phrase from the truth that the surveying equipment generally utilized is the chain. Chain surveying is that type of surveying in which simply linear measurements are made in the field.

Chain surveying is one of the simplest methods of land surveying. It is the type of surveying in which just linear measurements are made, no angular measurements are taken.


What Is Surveying?

Even in ancient times, there was a need for land surveys in order to determine the extent of land, area of ​​land, and use of land.

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Land Survey

Major Projects of Engineering such as railways, water supply pipelines, dams, canals, roads, sewage, wastewater, buildings, bridges, etc. have to be planned and studied before construction.

Planning of the project requires information such as the topography of the soil surface and other project-related results. This information can be obtained through surveys of land.

For Example: Before the construction of the dam, information such as areas submerged by a dam, villages to be relocated, water collected in lakes, etc are required in order to precede dam construction. Such information can be acquired through surveying.


Principles Of Surveying

Surveying involves different actions, practices, and methods. Such procedures are based on the simple and unique principles of surveying, which tend to provide simplicity and accurateness to the act of surveying. These principles are totally derived from the experiences and observations of the surveying experts.

While surveying one should Keep them in mind which can help eliminate errors and maintain accuracy in surveys.

The main principles of the survey are as follows:

  • The first principle of surveying is to work from whole to the Part.
  • Setting up new station position by at least using two Independent Processes of Surveying.
  • There are many processes in surveying, but in order to perform a specific type of work, the surveyor must select the most accurate and suitable process for surveying.
  • Data obtained from surveying should be recorded and maintained properly for further use.

Read More: Theodolite | Transit Theodolite | Types of Theodolite | Theodolite Parts | Uses Of Theodolite | Theodolite Survey


What Is Chain Surveying?

The chain survey is the easiest method of surveying. It is the method of surveying in which the area is allotted into a network of triangles and the sides of the several triangles are measured quickly in the field with chain or tape.

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Chain Surveying

In the chain surveying, simply the measurements are taken in the field, and the rest work, such as plotting computation, etc. is done in the office.

Surveying is sufficient for surveys of a small extent on open ground to maintain data for an exact description of the boundaries of a piece of land or to obtain simple details. It is the simplest and accurate method of land surveying, in this, linear distances are calculated on the field. This is a very simple method of surveying.

The principle of chain survey or Chain Triangulation, as is sometimes called, is to give a skeleton or framework that contains a number of connected triangles, as the triangle is just a simple draw that can be plotted from the lengths of its sides calculated in the field book.

For decent results in plotting, the framework should be consist of triangles that are as almost equilateral as possible.


Principles Of Chain Surveying

The major principle of chain surveying is to divide the area to be surveyed into a network of connected triangles as a triangle is just a simple diagram that can be plotted from the lengths of its sides measured in the field.

Since triangulation forms the principle of chain surveying, the chain survey is similarly sometimes called chain triangulation.

If the area to be surveyed is triangular and if the lengths and sequence of its three sides are recorded, the plan of the area can be easily drawn.

However, if the area has more than three straight boundaries, for instance as in figure (a) it is no longer enough to measures the lengths of the sides completely.

The field measurements must be so arranged that the area can be plotted by laying down triangles. Various arrangements should be prepared to satisfy this condition but only two are given here as shown in figure (b) and (c).


Types Of Equipment Used In Chain Surveying

The several types of equipment used in chain surveying are as follows.

  1. Chain
  2. Arrows
  3. Pegs
  4. Ranging Rods
  5. Plumb Bob
  6. Hammer
  7. Cross Staff
  8. Offset

1. Chain

In chain surveying chains are the considerably essential equipment for the procedure of survey. Chains are utilized to measure horizontal distances. Chains are created of straight links of galvanized mild steel wire named links.

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Chain

The ends of each link are bent into a looped hand connected using three oval rings which afford flexibility to the chain. The chain is formulated of mild steel. The ends of the chain are given brass handles for dragging the chain on the ground.

The outside of the handle is the zero points or the endpoint of the chain and the length of the chain is assessed from the outside of one handle to the outside of the additional. The length of a link is the distance between the centers of the two consecutive intermediate rings. The end links contain the handles.


2. Arrows

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Arrow

These are the marking pens made of steel wire and mainly, 10 arrows are given with a chain survey. Length may differ from 25 mm to 50 mm but indicated length as per the IS-Code.

The arrow is made sharp and another end is bent into a loop or circle for the facility of carrying. The usage arrows are injected into the ground after every chain length measured on the ground.


3. Pegs

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Metal Survey Peg With Red Flag

Pegs are utilized to mark the position station or terminal point of a survey line. They are pushed in the ground with the support of the wooden hammer and kept 40 mm above the ground surface.

The dimension of pegs is mainly 150 mm long and 30 mm square at the top. Pegs are generally available of wooden.


4. Ranging Rods

Ranging rods are 2 m – 3 m high rods of steel or well-seasoned wood utilized the ranging of point. They are coated in alternate colors of the band either white & black, white & red, or black, white, and red in series.

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Ranging Rod

The band is of length 200 mm, so that can be utilized for the rough measurement of smaller length 2 m ranging rod being more popular. They are octagonal or circular in cross-sections of 30 mm diameter and are almost invisible at a distance of 200 m.

They are given with the white or yellow flag 0f 30 – 50 sq. cm area tied near its stop.


5. Plumb Bob

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Plumb Bob

While chaining along the sloping surface of the ground, a plumb bob is required to transfer the points to the ground. It is similarly utilized for accurate centering of the theodolite compass, plane table, etc over a station mark and for assessing the vertically of ranging poles.


6. Hammer

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Hammer

Hammer is used to driving the pegs and wooden pegs into the earth. Because some hard soil surface hammer is must to insert the pegs into the soil


7. Cross Staff

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Cross Staff

This is the tool utilized for setting out right angles to a chain line. It includes either the frame or box with two pairs of vertical slits and is mounted on a pole shoe for fixing in the ground.

The three types of cross staff,

  • Open cross-staff
  • French cross-staff
  • Adjustable cross-staff

8. Offset

The offset rod is the same as that of the ranging rod. They are should with a pointed iron shoe at one end and given with a notch or a hook at the different for pushing or pulling the chain through hedges or different obstructions.


Types Of Chains Used In Surveying

Depending upon the length of the chain, these are divide into the following types,

  1. Metric chains
  2. Steel band or Band chain
  3. Gunter’s chain or surveyor’s chain
  4. Engineer’s chain
  5. Revenue chain

1. Metric Chains

Metric chains are the most commonly utilized chain in India. These types of chains come in various lengths such as 5 m, 10 m, 20 m, and 30 m. The most commonly utilized is a 20 m chain.

Tallies are given at every 2 m of the chain for quick reading. Every link of this type of chain is 0.2 m. The total length of the chain is noted on the brass handle at the ends.


2. Steel Band Or Band Chain

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Steel Band Chains

These types of chains consisting of a long narrow strip of steel of uniform width of 12 mm to 16 mm and thickness of 0.3 mm to 0.6 mm. This chain is divided by brass studs at every 20 cm or instead of brass studs, the band chain may have graduated carving as a centimeter.

For easy usage and workability, band chains are wound on steel crosses or metal reels from which they can be handily unrolled. These steel bands are accessible in 20 m and 30 m length and the width of about 12mm to 16mm.


3. Gunther’s Chain Or Surveyor’s Chain

A Gunter’s chain is 66 feet lengthy and contains 100 links, each link 0.66 feet lengthy (7.92 inches). It was originally obtained for comfort in land measurement since 10 square chains are equal to 1 acre, also while measuring linear measurement.

  • 10 Gunter’s chain = 201.17 meter
  • 80 Gunter’s chain = 1609.36 meter

Read More: What Is Total Station | Components of Total Station | Advantages of Total Station | How to Use Total Station In Surveying | Uses of Total Station | Types of Total Station


4. Engineer’s Chain

Being 100 feet long and contains 100 links, each link being 1 foot. At every 10 links brass tags are clamped with notches specifying 10 links segments.

The usages of the engineer’s chain are mainly measured to Feet.


5. Revenue Chain

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Revenue Chain

The Revenue chain is 33 feet lengthy and contains 10 links each link is 2 feet 0.75 inches long, the chain in surveying is utilized for measuring fields in cadastral survey.


Procedure Of Chain Surveying

The procedure of chain surveying is as follows,

1.Reconnaissance: The preliminary inspection of the to be surveyed is named the reconnaissance. The surveyor evaluates the area to be surveyed, surveys, or prepares an index drawing or key plan. He should also evaluate the problems of plotting the survey line and supplementary work.

2. Marking Station: The survey fixed up the required no. of stations at the spot from where the maximum possible station can be plotted

Some Operation:- 

  • Fixing of ranging rod or poles.
  • Driving pegs.
  • Making a cross (X) if the surface is hard.
  • Digging & fixing a stone.

3. Choose a way for passing the mainline. Which should be as horizontal and clean as feasible and should be passed almost through the center of work.

4. The ranging rods are fixed on the station.

5. After fixing the stations, a chain in could be initiated.

6. Make ranging where ever essential.

8. Measure the chain edge and offsets.

9. Enter the observation and measurement in the field book.


Errors In Chain Surveying

Errors in chaining may be classified as,

  • Personal Errors
  • Compensating Errors
  • Cumulating Errors

1. Personal Errors

The personal errors include incorrect recording, reading from the incorrect end of the chain, etc., which are personal errors. These errors are serious and cannot be inspected easily. Care should be taken to prevent such kinds of errors.


2. Compensating Errors

This type of error may be sometimes positive and sometimes negative. Thus they are likely to get compensated when a large number of readings are obtained. The magnitude of such errors can be assessed by the theory of probability. The following are the examples of the errors,

  • Wrong marking of the end of a chain.
  • A fractional part of the chain may not be accurate though the total length is corrected.
  • Graduations in the tape may not be similar throughout.
  • In the method of stepping while assessing the sloping ground, plumbing may be crude.

3. Cumulating Errors

The errors that arise often in a similar direction are called cumulative errors. In each reading, the error may be small, but when a large number of measurements are given rise to they may be considered since the error is often on one side. Some examples of such errors are:

  • Bad ranging
  • Bad straightening
  • Erroneous length of chain
  • Temperature deviation
  • Variation in applied pull Non-horizontality
  • A sag in the chain, if discontinued for measuring horizontal distance on sloping ground.

Advantages Of Chain Surveying

The advantages of the chain surveying method are as follows,

  • Chain survey is the easiest and commonest method utilized in surveying exercises.
  • The equipment utilized to conduct a chain survey is simple to utilize.
  • The equipment utilized in the chain survey can easily be replaced. For instance, measuring rods can be replaced with measuring tape.
  • This method does not involve complicated mathematical computations. This is a relief for those who are afraid of mathematics.
  • In a chain survey, a limited number of people are required to perform the survey. Generally, the chain survey team has three people Booker, leader, and follower.

Disadvantages Of Chains In Surveying

Chain surveying has following disadvantages,

  • A simple chain survey cannot be performed in built-up areas and huge areas.
  • A simple chain survey is subject to various changes of errors of accumulation which may cause by the difficulty of the chain.
  • The chain linkage may fail to stretch up appropriately and result in wrong data. Similarly clogging of the chain may read to an error in reading.
  • It is time-consuming.
  • It may not be performed in areas with steep slopes or waterlogged areas. Chain survey is generally performed in dry areas with gentle slopes.
  • It becomes more difficult when the survey is performed in areas that are too wet.
  • Chain survey becomes a more difficult method when there are raised points (obstacles) in between areas to be surveyed.

Line Types In Chain Surveying

There are four lines for chain surveying,

  1. Base Lines
  2. Chain Line (Main Survey) Lines
  3. Tie (Subsidiary) Lines
  4. Check (Proof) Lines

1. Base Lines

In the chain survey graphs, the three lines of a triangle that depend on one line are called the baselines. The accurateness of the chain surveying, based on the accuracy of the baseline.

For this, the lengthy line between the survey structure and the line between the area is carried as the baseline. Depends on the line and even flat ground, the measurement is determined with less difficultly.

Basically, the line should be computed at least twice in the opposite direction. On the map, the survey lines are shown along the dotted lines and in the middle of the breaks.


2. Chain Line (Main Survey) Lines

The lines that join main stations are termed chain lines or main survey lines.


3. Tie (Subsidiary) Lines

Tie lines join two fixed points on the chain line. The benefit of tie-line appears while checking surveying exactness in locating interior details such as buildings and ways.


4. Check (Proof) Lines

It joins the triangle apex to some fixed points on any two sides of a triangle. It is utilized to evaluate the accuracy of the framework. The length of the check line measured on the ground surface shall be consistent with its length on the plan.


Obstacles In Chain Surveying

There are three obstacles in chain surveying,

  1. Obstacles To Ranging
  2. Obstacles To Chaining
  3. Obstacles To Both Ranging And Chaining

1. Obstacles To Ranging

This type of obstacle in which the ends are not intervisible is relatively common except in a flat region. These may be two cases.

  • Both ends of the line may be visible from the middle points on the line.
  • Both ends of the line may not be visible from the middle points on the line.

2. Obstacles To Chaining

The obstacle to chaining prevents chain measuring immediately between two points and rises to a set of difficulties in which distances are found by indirect measurement.

Read More: What Is Surveying | 23 Types of Surveying Equipment | Surveying Instruments and Their Uses


3. Obstacles To Both Ranging And Chaining

The obstacle to ranging and chaining may be in the two cases,

  • When it is likely to chain around the obstacle. For example, a pond, etc.
  • When it is not likely to chain around the obstacle. For example, a river.

Offset In Chain Surveying

The offsets are the lateral measurement from the surveying lines to fixed the position of various objects concerning the survey lines. The types of offset,

  1. Perpendicular Offsets
  2. Oblique Offsets

1. Perpendicular Offsets

When the angle of the offsets is 90° degrees. It is named perpendicular offsets.

Perpendicular offsets are also categories two types,

  • Pythagoras theorem
  • Swing method

Pythagoras Theorem

This method is utilized to draw perpendicular offsets and it depends on the principle of the Pythagoras theorem.

Swing Method

This method is similarly utilized to draw perpendicular offsets in chains in surveying and another survey. It depends on the principle that the shortest distance of any two-point is nothing but the perpendicular distance.


2. Oblique Offsets

When the angle of offsets is any different angle but not be 90°. It is named oblique offsets. Oblique offsets are extremely used in chain surveying.


Recording the measurements in the Field Book (Field Measurement Book)

Chain and tape measurements are maintained in a separate book, such a book is called the field book. Such a book usually has dimensions usually 20 cm X 12 cm and opens length-wise.

Field Book should contain good quality stout opaque paper which can uphold small damage on-field and maintain information in a readable manner. It should be also well-bounded to avoid paper loss and of a size convenient for the pocket.

One of the important requirements of the chain line is that it should be represented either by a single line or by two lines separated 1 to 2 cm apart and ruled down the middle of each page.


1. Single Line Filed Book

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Single Line Field Book

Single line field books are used for a comparatively larger area for more detailed dimension work. In such field books, the chain line starts from the bottom of the page and respectively works upward direction.

Read More: Contour Interval | Index Contour | What are Contour Lines | How to Find Contour Interval


2. Double Line Filed Book

What Is Chain Surveying | Principles Of Chain Surveying | Chaining In Surveying | Chain Surveying Procedure | Types of Chain Surveying | Obstacles In Chain Surveying
Sample of Double Line Field Book

The double-line field book shown below in the drawing is the most commonly used for performing ordinary survey works. The observed distance is along the chain which is entered between the two lines of the page.

The double line field books all the distances along the chain line are entered between the spaces within the two ruled lines while the offsets obtained are entered left or to the right respectively of the chain line, according to the case.


FAQs

Chain Survey

The chain survey is the method of surveying in which the area is allotted into a network of triangles and the sides of the several triangles are measured quickly in the field with chain or tape.

Principles of Chain Surveying

1. The major principle of chain surveying is to divide the area to be surveyed into a network of connected triangles as a triangle is just a simple diagram that can be plotted from the lengths of its sides measured in the field.
2. Triangulation forms the principle of chain surveying, hence the chain survey is also called chain triangulation.
3. If the area to be surveyed is triangular and if the lengths and sequence of its three sides are recorded, the plan of the area can be easily drawn.

What is Chain Survey and its types?

The chain survey is the method of surveying in which the area is allotted into a network of triangles and the sides of the several triangles are measured quickly in the field with chain or tape.
Types Of Chains Used In Surveying
1. Metric chains
2. Steel band or Band chain
3. Gunter’s chain or surveyor’s chain
4. Engineer’s chain
5. Revenue chain

What does Chain surveying require?

The several types of equipment used in chain surveying are as follows,
1. Chain
2. Arrows
3. Pegs
4. Ranging Rods
5. Plumb Bob
6. Hammer
7. Cross Staff
8.Offset

What are the advantages of chain surveying?

The advantages of the chain surveying method are as follows,
1. Chain survey is the easiest and commonest method utilized in surveying exercises.
2. The equipment utilized to conduct a chain survey is simple to utilize.
3. The equipment utilized in the chain survey can easily be replaced. 
4. This method does not involve complicated mathematical computations. 
5. In a chain survey, a limited number of people are required to perform the survey.

Chain Surveying

Chain surveying is the branch of surveying in which simply linear measurements are made in the field. This is desirable for the survey of small areas with simple details and a relatively flat area.

Types of Chains In Surveying

The following are different types of chains used in surveying,
1. Metric chains
2. Steel band or Band chain
3. Gunter’s chain or surveyor’s chain
4. Engineer’s chain
5. Revenue chain


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Post Contents Introduction To Chain SurveyingWhat Is Surveying?Principles Of SurveyingWhat Is Chain Surveying?Principles Of Chain SurveyingTypes Of Equipment Used In Chain Surveying1. Chain2. Arrows 3. Pegs 4. Ranging Rods 5. …

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