Define fly leveling and profile leveling

Define fly leveling and profile leveling
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Answer :

Fly Leveling adopted to transfer bench marks from one place to other .In this leveling only FS & BS are taken. 

Profile leveling:- The operation in which the object is to determine the elevation of points at known distanced apart along a given line to obtained the accurate outline of the surface of the ground 
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Related questions

State the purposes of following methods of leveling. i)Profile leveling, ii)Fly leveling, iii)Check leveling iv)Reciprocal leveling

Description : State the purposes of following methods of leveling. i)Profile leveling, ii)Fly leveling, iii)Check leveling iv)Reciprocal leveling

Last Answer : 1. Profile leveling- To determine the undulation of ground surface along given line for alignment of road, canal or pipe, railway line 2. Fly leveling-It is used to for connecting B.M. to ... is used to find the difference in leveling between two points two point obstructed due to river or pond.

What is meant by profile leveling and cross-sectioning ?

Description : What is meant by profile leveling and cross-sectioning ?

Last Answer : profile leveling : To know the nature of the ground surface the profile leveling is done along the Centre of the road at some regular intervals if required, staff readings may also be taken at points ... surface transverse to the Centre of the road. The length depend upon the nature of the work.

State the important point to be remembered while doing profile leveling.

Description : State the important point to be remembered while doing profile leveling.

Last Answer : 1. The chainage of staff stations are continuous from beginning to the end of the section line. 2. Readings of B.S. and F.S. should be taken very accurately with the bubble exactly in ... their width or by offset. 5)All the temporary adjustments at all instrument position shall carefully be done. 

Explain the procedure for profile leveling with neat sketch.

Description : Explain the procedure for profile leveling with neat sketch. 

Last Answer : 1) Let PQR be the given line of section.   2) Mark point at 10 m intervals on this line. 3) Level is set up on a firm ground at a suitable point I1. 4) Temporary adjustment of level is done and B. ... and set up on firm ground at I2 as before. 10) B.S is taken on CP1 and new HI is calculated  

Explain the procedure of profile leveling for construction of road.

Description : Explain the procedure of profile leveling for construction of road.

Last Answer : 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 ... points are plotted against their chainage to obtain ground profile along the alignment.

Define Change point and its necessity in leveling.

Description : Define Change point and its necessity in leveling.

Last Answer : Change point : It is the point at which both backsight and foresight readings are taken before and after shifting the level instrument. Necessity of change point in leveling : It is ... observations from single station due to large area, abrupt ground level variation and unavoidable obstruction. 

Define leveling.

Description : Define leveling.

Last Answer : Levelling is an ‘art of determining relative heights or elevations of different points on the earth’s surface so that the same may be represented on a plan or map’. It is essentially a process dealing with the measurements in vertical plane.

Write errors in leveling and corresponding precaution

Description : Write errors in leveling and corresponding precaution

Last Answer : i) Instrument error with respect to bubble tube, leveling staff. 1.If bubble tube is sluggish it may apparently be in the center though the bubble line is not horizontal. Precaution - ... reading. Precaution- Leveling should be properly done by bringing the bubble of bubble tube at Centre.

State different types of leveling. Explain any one in brief.

Description : State different types of leveling. Explain any one in brief.

Last Answer : Types of Levelling  1. Simple Levelling.  2. Differential Levelling.  3. Fly Levelling.  4. Longitudinal or profile leveling.  5. Cross-Section Levelling.  6. Check Levelling.  1. ... B are taken. The difference of these readings gives the difference of level between A and B. 

State sources of error in leveling.

Description : State sources of error in leveling. 

Last Answer : There are three sources of Error a) Instrumental Error :- Imperfect permanent adjustment Sluggish bubble Faulty focusing tube The erroneous leveling staff b) Refraction Error ( error due ... in manipulation  Mistake in reading the rod   Errors in sighting   Mistakes in recording

Describe instrumental errors in leveling.

Description : Describe instrumental errors in leveling.

Last Answer : The leveling process requires two instruments namely level and staff. The instrumental errors related to these are1. Error due to imperfect permanent adjustment: When the instrument is not in perfect ... the leveling staff may not be perfect. These errors can be neglected for ordinary work.

State under what situations differential leveling and reciprocal leveling is adopted.

Description : State under what situations differential leveling and reciprocal leveling is adopted.

Last Answer : 1. Differential leveling is adopted when i. The points are at a great distance apart. ii. The difference of elevation between the points is large. iii. There is obstacle between the points. ... or valley as it is not possible to place the level midway between two points on opposite banks.

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

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

Last 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 ... 2. Permanent bench mark. 3. Arbitrary bench mark. 4. Temporary bench mark.

Describe in brief profile levelling.

Description : Describe in brief profile levelling.

Last Answer : The operation of taking levels along the center line of any alignment at regular interval is called longitudinal or profile levelling. Along the alignment, spots are marked at regular interval ... the points are plotted against their chainage to obtain ground profile along the alignment.

What is fly levelling? When it is carried out?

Description : What is fly levelling? When it is carried out?

Last Answer : Fly levelling- It is the levelling operation in which only BS and FS are taken and no intermediate sights are observed. It is carried out when 1. To connect the BM to the starting point of ... BM. 3. To determine approximate reduced levels of points carried out with more speed and less accurate.

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.

Last Answer : Ans: When DifferentialLevelling is done in order to connect a bench mark to the starting point of the alignment of any project, it is called as fly levelling. Fly levelling is also done to connect ...  ii)if distance is more between two points.  iii)if there obstacles between the two points.  

Define : 1) Bench mark 2) Datum surface 3) Line of collimation 4) Change Point

Description : Define : 1) Bench mark 2) Datum surface 3) Line of collimation 4) Change Point 

Last Answer : 1) Bench mark: - It is a fixed reference point of known elevation.. 2)Datum surface :-It is any arbitrarily assumed level surface from which vertical distance are measured 3) Line of collimation:- ... which the fore and back sights are taken.  It is the point denoting the shifting of the level.

Define: WCB and Quadrantal Bearing system

Description : Define: WCB and Quadrantal Bearing system

Last Answer : Ans.: 1)WCB:-In this system the bearing of a line is always measured clockwise for the north point of the reference meridian towards the line round the circle the angle thus measured is called ... the bearing of a line is measured clockwise from the north point or south point whichever is nearest .

Define orientation. State two methods of orientation. Which method is most accurate and why?

Description : Define orientation. State two methods of orientation. Which method is most accurate and why? 

Last Answer : Orientation is the process of keeping plane table in same position as that is occupied in previous station. Methods of orientation: i) Magnetic meridian method using trough compass ii) Back ... and not by using trough compass. Therefore there is no error occurring due to local attraction.

Define the terms i) Fore Bearing, ii) Open traverse, iii) Closing error, iv) Reduced bearing

Description : Define the terms i) Fore Bearing, ii) Open traverse, iii) Closing error, iv) Reduced bearing

Last Answer : i) Fore bearing : The bearing observed in the direction of progress of survey in clockwise manner is called fore bearing  ii) Open traverse : When the first and last survey lines does ... north or south direction in clockwise or anticlockwise manner is known as reduced or quadrantal bearing. 

Define Dip and deflection of needle.

Description : Define Dip and deflection of needle.

Last Answer : Dip of the magnetic needle: It is the upward or downward movement of magnetic needle in vertical plane due to earth's gravitational force is known as dip of needle. Deflection of needle : ... west direction, that horizontal angle between magnetic and true north is said to be declination of needle.

Define horizontal line and vertical line.

Description : Define horizontal line and vertical line.

Last Answer : Horizontal line : A straight line tangential to the level line and perpendicular to the plumb line is called horizontal line.  Vertical line : A line perpendicular to horizontal line and coinciding plumb line is known as vertical line

Define local attraction. State two causes of local attraction.

Description : Define local attraction. State two causes of local attraction.

Last Answer : Local attraction: It is the deviation or deflection of magnetic needle from its normal position under influence of external magnetic forces is called as local attraction. Causes of local attraction : 1. Iron ... structure 2. Electric cable line 3. High voltage current 4. Bunch of key 5. Steel Tape 

Define : i) Traversing ii) Magnetic Meridian

Description : Define : i) Traversing ii) Magnetic Meridian

Last Answer : i) Traversing : Traversing is the series of survey lines connecting successive established traverse stations along the route of survey  ii) Magnetic Meridian : The direction indicated by ... and properly balanced Magnetic needle unaffected by local attractive force is called magnetic meridian.

Define true bearing and magnetic bearing.

Description : Define true bearing and magnetic bearing.

Last Answer : 1. True bearing – (i) The angle between true meridian or geographical north and any line known as true bearing. 2.Magnetic bearing-(i)The angle between magnetic meridian and any line is known as magnetic bearing.

Define surveying.

Description : Define surveying.

Last Answer : Surveying- It is branch of civil engineering in which relative positions of ground points are determined by taking linear and angular measurement.

Define- 1. Whole circle bearing 2. Reduced bearing 3. Fore bearing 4. Back bearing

Description : Define- 1. Whole circle bearing 2. Reduced bearing 3. Fore bearing 4. Back bearing

Last Answer : 1.Whole circle bearing-  The bearing measures only in the clockwise direction from meridian or north direction is known as whole circle bearing. 2.Reduced bearing  The bearing measures with ... bearing  The bearing observed in the direction of opposite of survey is called fore bearing. 

Define- 1. Datum 2. Change point

Description : Define- 1. Datum 2. Change point

Last Answer : 1. Datum- It is the imaginary level surface or level line from which the vertical distance of different points are measured.  2. Change point- It is the point at which both back sight and foresight readings are taken before and after shifting the level instrument. 

Define surveying & state its objectives

Description : Define surveying & state its objectives

Last Answer : Surveying- It is branch of civil engineering in which relative positions of ground points are determined by taking linear and angular measurement. Objectives: 1. To determine the relative positions of ... quantities 4. To prepare a topographical map showing details of hills, valleys and rivers.

Define: i) Level Line, ii) Horizontal Line, iii) Vertical Line iv) Bench Mark.

Description : Define: i) Level Line, ii) Horizontal Line, iii) Vertical Line iv) Bench Mark. 

Last Answer : j) Level Line: It is line lying in a level surface; it is therefore, normal to the plumb line at all points. ii) Horizontal Line: It is a straight line tangential to the level line at a ... RL determined with reference to the datum line. They serve as reference points for finding RL of new points. 

Define orientation and principle of plane tabling.

Description : Define orientation and principle of plane tabling. 

Last Answer : Orientation: The orientation of plane table means keeping the plane table at all stations parallel to the position it occupied at first station. Principles of plane table survey: 1. The rays drawn from ... same as that of previous station i.e. orientation should be done at each changed station.  

Define base line and check line with neat sketch.

Description : Define base line and check line with neat sketch. 

Last Answer : 1)Base Line : The longest line running roughly through the middle of the area to be surveyed is known as base line 2) Check line: The line joining the apex of a triangle to some fixed point on the ... A line joining some fixed point on any two sides of a triangle is known as check line. 

Define: i) Mean sea level, ii) Station point.

Description : Define: i) Mean sea level, ii) Station point. 

Last Answer : i) M.S.L: Mean sea level is the average height of the sea for all stages of tides. It is determined by averaging the hourly tide heights over a long period of 19 years at a place.  ii) Station ... is a point which is to be established at a given elevation or it is a point where the Staff is held 

Define: i) W.C.B. ii) Reduced Bearing

Description : Define: i) W.C.B. ii) Reduced Bearing

Last Answer : i)Whole circle bearing: The bearing measures only in the clockwise direction from meridian or north direction is known as whole circle bearing.   ii) Reduced bearing: The bearing measured ... north or south direction in clockwise or anticlockwise manner is known as reduced or quadrant bearing 

Define: i) Open Traverse ii) Closed Traverse.

Description : Define: i) Open Traverse ii) Closed Traverse. 

Last Answer : i) Open traverse: When the first and last survey lines does not meets at common point and hence does not form a closed polygon, then it is said to be open traverse.  ii) Closed Traverse: When last and first survey stations meet at common point, traverse is called as closed traverse.

Define ‘ Fore bearing ’ & ‘ back bearing ’ of line with a neat sketch

Description : Define ‘ Fore bearing ’ & ‘ back bearing ’ of line with a neat sketch

Last Answer : Fore bearing : The bearing of line observed in the direction of progress of survey is called fore bearing of the line. Bearing of line AB is observed at A' towards B' is called as fore bearing of the line ... The bearing observed at B' towards A' is called as back bearing of the line AB'  

Define the terms - Foresight, back sight, intermediate sight and change point.

Description : Define the terms - Foresight, back sight, intermediate sight and change point.

Last Answer : 1. Fore sight: It is the last staff reading from any set up of the leveling instrument and indicates the shifting of the instrument or end of leveling work. 2. Back sight: It is the first staff reading ... point fore sight is taken from one set up and a back sight is taken from the nest set up. 

Define the terms - dip of needle, magnetic bearing, fore bearing and back bearing.

Description : Define the terms - dip of needle, magnetic bearing, fore bearing and back bearing.

Last Answer : Dip of needle: It is downward inclination or small angle made by freely suspended magnetic needle with the horizontal. Magnetic bearing: Magnetic bearing of a survey line is the horizontal angle ... of line measured in backward direction or opposite direction of survey, is known as back bearing.

State any four types of offsets and define them.

Description : State any four types of offsets and define them. 

Last Answer : i) Long offset: If length of offset more than 15 m. ii) Short offset: If length of offset less than 15 m. iii) Perpendicular offset: Offset taken perpendicular to chain line. iv) Oblique offset: Offset not taken perpendicular to chain line.

Define the term – base line and check line.

Description : Define the term – base line and check line.

Last Answer : Base line: Base line is generally the longest line running roughly through the middle of the area. It is laid on a level ground as far as possible. The whole frame work is built upon this line. ... point on the opposite side or a line joining some fixed point on any two sides of the triangle.

Define the term: (1) Level surface (2) Line of collimation

Description : Define the term: (1) Level surface (2) Line of collimation

Last Answer : Level surface: It is a surface parallel to the mean spheroidal surface of the earth. It is normal to the direction of plumb line at all points. The surface of still water is an example of level ... to the optical center of object glass and its continuation. It is also called as line of sight. 

Define the following: (i) Height of instrument (i) Back sight (iii) Fore sight (iv) Axis of bubble tube

Description : Define the following: (i) Height of instrument (i) Back sight (iii) Fore sight (iv) Axis of bubble tube

Last Answer : i. Height of instrument: It is the reduced level of line of collimation when the leveling instrument is properly leveled. It is obtained by adding the BS reading to RL of bench mark or change point on which the ... when the bubble is at the center of its run i.e. at middle point of the tube.

Define the following terms: (i) Level surface {ii) Datum line (iii) Reduced level (iv) Axis of telescope

Description : Define the following terms: (i) Level surface {ii) Datum line (iii) Reduced level (iv) Axis of telescope

Last Answer : i)Level Surface : Any surface is parallel to mean spheroidal surface of earth is said to be a level surface. The water surface of still lake is also considered to be level surface. ii) ... an imaginary line passing through the optical Centre of object glass and optical Centre of the eye piece.

Define Local attraction.

Description : Define Local attraction.

Last Answer : Local attraction – when magnetic needle does not remain in N-S direction due to effect of magnetic substances present around the compass, such error at station is known as local attraction. 

Define: (i) Long offset (ii) Short offset

Description : Define: (i) Long offset (ii) Short offset

Last Answer : i. Long offset: The offset whose length is more than 15 m. ii. Short offset: The offset whose length is less than or equal to 15 m.

Define: (i) True meridian (ii) Magnetic meridian

Description : Define: (i) True meridian (ii) Magnetic meridian

Last Answer : i. True meridian: It is line of intersection of plane passing through North Pole, South Pole and point under consideration.  ii. Magnetic meridian: Magnetic meridian at point is direction shown by freely suspended magnetic needle at that point.

Define Ranging. State types of ranging.

Description : Define Ranging. State types of ranging.

Last Answer : Ranging: It is process of locating points on ground along straight line. Types of ranging: 1. Direct ranging. 2. Indirect ranging

Define bench mark and enlist the types of bench mark.

Description : Define bench mark and enlist the types of bench mark.

Last Answer : It is fixed reference point of known or assumed elevation. It is used either as a starting point for levelling or as a check while closing. There are four kinds of bench marks. i. Great ... ) bench mark. ii. Permanent bench mark. iii. Arbitrary bench mark. iv. Temporary bench mark.

Define : 1) Change point 2) Height of instrument.

Description : Define : 1) Change point 2) Height of instrument.

Last Answer : 1) Change point It is point on which fore and back sights are taken. 2) Height of instrument. It is the reduced level of line of collimation when the leveling instrument is properly leveled. It is ... adding the BS reading to RL of bench mark or change point on which the staff reading was taken.

Define 1)Ranging 2)Chaining

Description : Define 1)Ranging 2)Chaining

Last Answer : 1) Ranging The method of establishing intermediate points on a straight line between the two fixed points is known as ranging. 2)Chaining The method of measuring the distance with the chain or tape is called as Chaining.