Plane table survey

Plane table survey is that type of survey in which the measurement of survey lines of the transverse a of the transverse and their plotting to a suitable scale are…

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Levelling and Principle of leveling

Levelling may be defined as the art of determining the relative height or elevants of points or objects on the earth’s surface. Instruments used for leveling: ·          Level ·          Levelling Staff Level: The…

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Theodolite survey

The theodolite is the most precise instrument used for measurement of horizontal and vertical angles. It can also be used for various surveying operations such as establishing grades, setting out…

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Compass survey

When the area to be surveyed is large, chain and compass surveying is preferable. A compass is used to measure the magnetic bearing of a line. There are two forms of…

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Calculation of Areas from offsets to a Base line

The area may be calculated by the rule: ·         ü Mid-ordinate Rule ·         ü Average ordinate Rule ·         ü Trapezoidal rule ·         ü Simpson’s Rule 1.Mid-ordinate rule: Area = (O1+O2+……….+on)d O1, O2   = the ordinates at the mid…

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Advantages and Disadvantages of chain surveying Advantages:

·         ü Chain surveying is suitable for fairly level ground ·         ü It does not require costly equipments ·         ü It is used for preparing plans of smaller area ·         ü It is simple Disadvantages ·         ü It is cannot…

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Instruments used for chain surveying

The various instruments used in chain surveying are as follows.  ·         ü chain ·         ü arrows ·         ü pegs ·         ü ranging rods ·         ü offset rods ·         ü plumb bob 1.  Chain: Chains are used to measure horizontal distances. Chains are…

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 Measurement of Distance with Chains or Tapes

Measurement of distances using chain or tape is termed as chaining. This is the accurate and commonly employed method in surveying: These instruments can be classified as chains Steel band Tapes…

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Chain Surveying – Instruments used in Chaining

Chain survey is suitable when Area to be surveyed is comparatively small and the Ground is fairly level. Chain survey can also be used when the Area is open and Details to…

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Compass Surveying and How to use a Compass

Compass is an instrument which can be used to measure the direction of a survey line with respect to magnetic north-south. The magnetic north-south direction which is the reference direction is called…

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