Explain importance of Bench mark in leveling and state the types of Bench mark.

Explain importance of Bench mark in leveling and state the types of Bench mark. 
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1 Answer

Answer :

Bench marks are fixed points or marks of known RL determined with reference to the datum line. These are very important points which serve as reference points for finding RLs of new points or for conducting leveling operations in projects involving roads, railways etc.

Types of bench mark:

1. GTS bench mark.

2. Permanent bench mark.

3. Arbitrary bench mark.

4. Temporary bench mark.


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