Explain the procedure of profile leveling for construction of road.

Explain the procedure of profile leveling for construction of road.
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The operation of taking levels along the center line of any alignment at regular interval is called longitudinal or profile leveling. Along the alignment, spots are marked at regular interval along with the apex points where the alignment changes the direction. Setting the level midway between ends of stretch of road which can be controlled from one point and spot levels are taken on the points on the center line of the alignment. The staff readings and chainage of the points are noted in the field book. The RLs of all the points are calculated and the elevations of all the points are plotted against their chainage to obtain ground profile along the alignment.

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Description : Explain how will you overcome the obstacles over river during chaining operation.

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Explain errors occurred due to manipulation and sighting in plane tabling.

Description : Explain errors occurred due to manipulation and sighting in plane tabling.

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Explain the radiation method of plane table survey with neat sketch.

Description : Explain the radiation method of plane table survey with neat sketch. 

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Description : Explain four types of meridians. 

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Explain dip of magnetic needle with neat sketch.

Description : Explain dip of magnetic needle with neat sketch. 

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Explain reciprocal ranging with neat sketch.

Description : Explain reciprocal ranging with neat sketch. 

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Description : Explain Direct method of chaining on sloping ground with neat skeetch. 

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Explain ‘Declination of Magnetic needle’ and types of declination.

Description : Explain ‘Declination of Magnetic needle’ and types of declination. 

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Explain Graphical adjustment of closing error in a closed traverse.

Description : Explain Graphical adjustment of closing error in a closed traverse.  

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Explain ‘Intersection Method’ of plane table surveying with neat sketch. Also give situation when intersection method is used.

Description : Explain ‘Intersection Method’ of plane table surveying with neat sketch. Also give situation when intersection method is used.

Last Answer : 1. Lay out a base line AB and measure it and Plot a distance ab' on sheet using any scale. 2.Set up instrument at A' with a' over A' 3.Orient the table by placing alidade ... the case of the survey of mountainous country. 5. The only linear measurement required is that of a base line.

Explain Fly Levelling with neat sketch. State situation under which fly levelling is needed.

Description : Explain Fly Levelling with neat sketch. State situation under which fly levelling is needed.

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Description : Explain Orientation of plane table by Back-sighting Method.

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Explain principle of chain surveying

Description : Explain principle of chain surveying 

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Explain indirect ranging with neat sketch

Description : Explain indirect ranging with neat sketch

Last Answer : Step wise procedure indirect ranging i.e. reciprocal ranging- Let A and B be the two station with rising ground or a hill intervening between them even i)Select any two intermediate station say M1 and N1 ... there position will be changed until finally they are both on the line A B exactly.