Enlist the advantages of Auto level. 

1 Answer

Answer :

Following are the advantages of auto level:

1) Operational Comfort: Use of Auto level is free of fatigue, does not cause strain on eyes, nerves etc.

2) High precision : Precision of auto level is about ± 0.5mm to 0.8 mm for one km

3) High speed: Time required for leveling is about half of that required with ordinary level.

4) Freedom from errors: Bubble usually remain in center and image of staff is erect, easy to read

5) Freedom from external influences: No influence of cloud, rain, magnetic field, vibrations, etc. on the levelling work with Auto level.

6) Range of application: Auto can be used for medium and large size project. To establish bench marks accurately.

Related questions

Description : State advantages of Auto-Level over dumpy level. 

Last Answer : 1) Auto level gives quick and easy leveling with less effort than dumpy level. 2) It is most accurate and precise which gives least error about 0.5 to 0.8 in 5 km. 3) It is simply ... readings to read; which reflects inverted in some dumpy level. 5) It gives more operational comfort to surveyor. 

Description : State four advantages of auto level.

Last Answer : Advantages of auto level: 1. More precise/accurate leveling can be done using these levels. 2. The telescope of this instrument needs only be approximately leveled over the tripod and then the ... it reduces operational fatigue. 5. Clear and erect image. 6. Light weight and compact.

Description : Enlist the methods of plane tabling. 

Last Answer : Method of Surveying with the plane table are : 1) Radiation 2) Intersection 3) Traversing 4) Resection

Description : Enlist various type of Bench Marks

Last Answer : 1) Great Trigonometrical Survey Bench marks 2) Permanent Bench marks 3) Arbitrary Bench marks  4) Temporary Bench marks

Description : Enlist different errors in compass surveying.

Last Answer : Various errors in compass surveying are classified asi) Instrumental errors. ii) Personal errors or observational errors iii) Errors caused due to external errors (natural errors) i) ... magnetic declination. c) Local attraction due to proximity of magnetic substances or magnetic field.

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.

Description : Enlist different accessories of plane table survey with their use. 

Last Answer : i) The plane table: It is used for fixing a drawing sheet over it.  To locate the position of the objects on the sheet by drawing rays and plotting to suitable scale. ii) The Alidade (plain Alidade ... v) U-Fork or Plumbing fork with plumb bob: It is used for centering the table over the station. 

Description : Enlist the factors affecting on selection of survey station or survey line in chain survey.

Last Answer : Following are the factors affecting on selection of survey station for chain surveying. 1) As far as possible the survey work should be based upon the basic principle of surveying i.e. working from whole ... level ground. 9) The survey lines should run as far as possible nearer to object.

Description : Enlist the sources of error in chaining and state the precautions to be taken against error.

Last Answer : In general, the distance measurement obtained in the field will be in error. Errors in the distance measurement can arise from a number of sources: 1. Instrument errors: A chain may be faulty due to a defect ... confuse 10 m tag with 20 m tag. It should be avoided by noticing the 15 m tag.

Description : Enlist method of ranging and explain any one in brief.

Last Answer : Ranging The method of establishing intermediate points on a straight line between the two fixed points is known as ranging. It is done before chaining started. It may be done by eye or by using some ... which are nearer to line AB. Repeat same process until points M and N are established.

Description : Enlist uses of survey.

Last Answer : Uses of surveys. 1. To record relative positions of various points on the surface of earth. 2. Prepare plans and maps required for various works. 3. Layout of various engineering works. 4. Compute ... . 5. To prepare a topographic map 6. To prepare military map 7. To prepare archeological map

Description : State advantages of plane table survey one each with respect to booking and suitability

Last Answer : Booking of observations: i) Field work and plotting work done simultaneously ii) ) Notes of measurement are seldom required and possibility of mistakes in booking is eliminated. Suitability of PT ... and work where great accuracy is not required. ii) Mostly suitable for survey in plain terrain

Description : State two advantages of telescopic alidade over simple alidade.

Last Answer : Advantages of telescopic alidade : i) Telescopic alidade is more accurate in bisection than simple alidade ii) Telescopic alidade is useful in comparatively longer range objects. iii) It can be easily ... is not possible by simple alidade. iv) It gives quicker bisection which saves time ultimately.

Description : Write any four advantages of intersection method of plane tabling over radiation method of plane tabling.

Last Answer : Advantages of intersection method: 1. Interection method requires less ground distance measurement than radiation method. 2. By this method we can locate inaccessible points which cannot be ... to radiation method, intersection method eliminates undulation error, bisection error and plotting errors.

Description : State four advantages and four disadvantages of plane table survey

Last Answer : Advantages: 1. A field book is not required. 2. Errors of booking in field book avoided. 3. Errors of plotting can be readily checked. 4. Suitable in magnetic area. 5. Survey work with ... cannot be done in rainy season. 5. Difficult to re-plot as field notes are not available.

Description : State the fundamental axes and mention their relationship for a dumpy level.

Last Answer : Fundamental axis of dumpy level are as follows; i) The vertical axis ii) The axis of bubble tube iii) The line of collimation iv) The axis of the telescope Relationship between ... iii) Axis of telescope and line of collimation should coincide when dumpy level is correctly leveled.

Description : State the important points kept in mind while recording the staff readings in level pages with respect first reading, intermediate reading, last reading, change point, carry forward from one page to next page-Remark

Last Answer : 1) First reading is on bench mark point and should be noted in back sight(BS) column 2) Intermediate reading (IS) should be taken on the points between first and last station. 3) Last reading ... column of next page 6) Remark column should have denote First and Last RL along with change points.

Description : Draw a sketch and explain how to find height of chajja or slab using dumpy level.

Last Answer : Explanation : 1. First the back sight reading is taken on floor level whose RL is known to us; from which RL of instrument axis can be find out by adding RL of BM and BS reading. 2. Now ... staff reading. 4. Finally height of chajja is calculated as RL of slab bottom -  RL of floor top.

Description : State fundamental lines and their relationships with each other of dumpy level.

Last Answer : Fundamental axes of dumpy level : i) The vertical axis ii) The axis of bubble tube iii) The line of collimation iv) The axis of the telescope Relations of Fundamental axes : i) The ... to the axis of the bubble tube. iii) Axis of telescope and line of collimation should coincide.

Description : State fundamental axis of dumpy level and give their relationship 

Last Answer : Fundamental axes of dumpy level : i) The vertical axis ii) The axis of bubble tube iii) The line of collimation iv) The axis of the telescope Relations of Fundamental axes : i) The ... parallel to the axis of the bubble tube. iii) Axis of telescope and line of collimation should coincide. 

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. 

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 

Description : What is Level surface & Datum surface

Last Answer : Level surface : It is surface parallel to the mean spheroidal surface of the earth.  It is normal to the direction of plumb line at all points. Datum surface : It is an arbitrary level ... may be referred. Vertical distances (elevations) of the points are measured with respect to this datum.

Description : State and explain temporary adjustments of dumpy level.

Last Answer : 1. Setting up the level. a. The level fixed on tripod. b. The legs of tripod stand are well spread so that the level will remain stable on tripod. c. Bring all the three foot screws ... screw till the image is distinct and clear. The cross hair on the diaphragm should also be seen clearly. 

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. 

Description : State any two desired relationship between fundamental axes of dumpy level.

Last Answer : Following are the desired relationship between fundamental axes of dumpy level. 1. The axis of level tube should be perpendicular to the vertical axis. 2. The line of collimation should be parallel to ... of bubble (level) tube. 3. Axis of telescope and line of collimation should be coinciding.

Description : State the important points kept in mind while recording the readings in level pages with respect first reading, intermediate readings, last reading, and change point, carry forward from one page to next page - Remarks. 

Last Answer : The following points should be kept in mind while recording the reading in level pages. 1. The first reading should be always noted as back sight (B.S.) 2. All the intermediate readings should ... horizontal line represents only one station. 8. Readings of each station should be in one line only.

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.

Description : As used in survey

Last Answer : It's the operation of changing the face of telescope from left to right and vice versa.

Description : The process of surveying is therefore in three stages namely:

Last Answer : (i) Taking a general view This part of the definition is important as it indicates the need to obtain an overall picture of what is required before any type of survey work is undertaken. In ... of quantities, datasheets, drawings and in land surveying maps and plan showing the features on the land.

Description : Tacheometric Surveying

Last Answer : Tacheometric is a branch of surveying in which horizontal and vertical distances are determined by taking angular observation with an instrument known as a tachometer. Tacheometric surveying is adopted in rough ... be prepared for investigation works within a short time on the basis of such survey.

Description : Explain the temporary adjustments of prismatic compass.

Last Answer : Temporary Adjustments of Prismatic Compass 1. Fixing the compass to the tripod The compass is fixed on a tripod by rotating screw head of tripod stand. 2. Centering the compass The prismatic compass ... prism is moved using focusing stud so that readings on graduated ring will be seen clearly. 

Description : Describe with neat sketch, the optical square and explain its principle.

Last Answer : Principal of optical square :- the angle between the first incident ray and the last reflected ray is twice the angle between the two mirrors OR If there are two plane mirrors whose reflecting surfaces ... is 450 while that between the first incident ray and last reflected ray is 900 .  

Description : What consideration would you have while selecting survey stations and survey lines in a chain survey?

Last Answer : Following points to be considered while selecting survey stations and survey lines 1) Main survey station should be mutually visible. 2) All triangles should be well conditioned. 3) The survey line should lie ... of the area so as to form the frame work of triangles on it to cover maximum area. 

Description : What are offsets? How are they taken and recorded? Explain with sketch.

Last Answer : Offsets are lateral measurement to the base line. They are Located by judgment if short And by instruments (optical square or cross staff) if long and measured by metallic tape and shown with their chainages on base line

Description : Define fly leveling and profile leveling

Last 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 ... known distanced apart along a given line to obtained the accurate outline of the surface of the ground 

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.

Description : State the situation where plane table is suitable. 

Last Answer : 1) It is most suitable for preparing small scale maps 2) It is suitable in magnetic are where compass survey is not reliable 3) It is most suitable for filling in details between stations fixed by triangulation 4) It is suitable where accuracy is not required.

Description : How would you detect presence of local attraction at a place ?

Last Answer : The presence of local attraction may be detected by finding difference of FB & BB of the line. If the fore bearing and back bearing difference is 1800 then there is no local attraction at both ... difference is not equal to 1800 then there is local attraction at both or any one station. 

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 .

Description : State the two uses of survey based on geodetic surveying

Last Answer : Two uses of survey based on geodetic surveying:- i) To determine the precise position s on the surface of the earth. ii) Preparation of maps of large area like map of a country, state ... ) Establishment of GTS bench Marks across the country. iv) Preparation of military maps for defense purposes.

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.

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.

Description : Explain temporary adjustment.

Last Answer : 1) Place the telescope parallel to foot screw (fig. a) 2) Bring the bubble at Centre by moving foot screw inward or outward simultaneously. 3) Then turn the telescope through 900 so that it ... 6) Once both positions give centered bubble, leveling of instrument is said to be completed.

Description : Draw sketch and explain method of traversing of plane table surveying. 

Last Answer : Procedure: 1.Set plane table over station A use plumbing fork for transferring station point from ground on sheet. Draw the direction of magnetic meridian with the help of compass. 2. With the ... scale Similarly, the table can be set at other successive station and traverse is completed.

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.

Description : Why zero is marked at south end on a graduated circle of prismatic compass?

Last Answer : As bearing of any line is measured with respective north direction, while observing north direction, reading should be 00 0'. Therefore when object vane is bisecting north direction, at the same ... get bearings with respective north direction always, zero is marked at south end of magnetic needle.

Description : State temporary adjustments of prismatic compass

Last Answer : a) Setting the prismatic compass over prefixed survey station b) Centering the compass over nail point of station using plumb bob c) Leveling of compass in horizontal plane using level tube d) Focusing of prism by raising and lowering the focussing stud

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. 

Description : Write the functions of the following components of prismatic compass i) Prism, ii) Lifting pin, iii) Prism cap, iv) Agate cap

Last Answer : i) Prism: Reading printed on horizontal face of compass ring can be read from vertical position  ii) Lifting pin: When the instrument not in use the sight vane passes against the lifting pin which lift ... piece of hard glass provided on top of pivoted point, to reduce wear and tear of the point