Describe any one method of orientation of plane table surveying

Describe any one method of orientation of plane table surveying
by

1 Answer

Answer :

Orientation by back sighting method:

This method is accurate and is always preferred.

Procedure:

1.Suppose A and B are two stations.The plane table is set up over A. The table is leveled by spirit level and centerd over station A so that point ‘a’ is just over station

A. The north line is marked on the right hand top corner of the sheet by trough compass.

2. With alidade touching a, the ranging rod at B is bisected and a ray is drawn. The distance AB is measured and plotted to any suitable scale .so, the point b represents Station B.

3.The table is shifted and set up over B. It is leveled and centered so that ‘b’ is just over B. Now the alidade is placed along the line ba, and the ranging rod at A is bisected by turning the table clockwise or anticlockwise . At this time the centering may be disturbed, and should be adjusted immediately if required. When the centering ,leveling and bisection of ranging rod at A are perfect ,then the orientation is said to be perfect.

image

OR
2.Orientation by magnetic needle:
 Procedure:
This method is suitable when local attraction is not suspected in the area.
1. Suppose A and B are two stations. The plane table is set up at station A. The centering is done by U-frame so that the point ‘a’ is just over A. Then the trough compass is placed on right hand top corner of the sheet in a such way that the needle coincides 0-0 mark. After this a line representing the north line is drawn through edge of the compass box.
2. With the alidade touching the point ‘a’ ,the ranging rod at B is bisected and a ray is drawn. The distance AB is measured and plotted to any suitable scale.
3. The table is shifted and centered over B, so that the point b is just over B.
The table is leveled .Now the trough compass is placed exactly along the north line drawn previously. The table is turned clockwise or anticlockwise until the needle coincides exactly with the 0-0 mark of the compass.
4. While turning the table ,care should be taken not to disturb centering. In case it is ,it should be adjusted immediately.
5. While the centering and leveling are perfect and needle is exactly at 0-0 , the orientation is said to be perfect.
image
by

Related questions

Compare radiation and intersection methods of plane table surveying on any two parameters.

Description : Compare radiation and intersection methods of plane table surveying on any two parameters. 

Last Answer : Radiation method Intersection method 1. It requires the plane table to occupy a single station.  1. This method requires setting the table up at minimum of two stations.  ... for locating inaccessible points by the intersection of the rays drawn from two instruments stations. 

State two advantages of plane table surveying

Description : State two advantages of plane table surveying

Last Answer : 1.it is most rapid method of surveying. 2. it is suitable for magnetic areas. 3.The map can be prepared easily ,and does not require greater skill. 4.Irregular objects can be represented ... is less costly. 7 The check lines detects the errors of measurement and plotting on field itself. 

Describe back sighting method of orientation of plane table surveying.

Description : Describe back sighting method of orientation of plane table surveying.

Last Answer : Backsight method of orientation 1. Assume we have to orient the table at next station B' represented on paper by point b'. 2.the line ba' is drawn on previous station A'. 3.the alidade is kept ... A'. 4. When the plotted line ab' coincides with line AB' and table will be oriented.

Mention different sources of errors in theodolite surveying.

Description : Mention different sources of errors in theodolite surveying.

Last Answer : Sources of errors in theodolite surveying:- i) Instrumental errors1) Non adjustment of plate bubble. 2) Line of collimation not being perpendicular to horizontal axis. 3) Line of collimation ... causes error due to irregular refraction. 2) High winds cause vibration in instrument.

Enlist the uses of total station in surveying.

Description : Enlist the uses of total station in surveying.

Last Answer : The uses of total station are : 1) To measure horizontal, vertical and slope distances. 2) To measure horizontal and vertical angles. 3) To measure the level difference between points. 4) To carry out ... 6) To prepare layout of building. 7) For speedy completion of any type of project work. 

Describe in brief resection method of plane table surveying.

Description : Describe in brief resection method of plane table surveying.

Last Answer : This method is used for establishing the instrument stations only. After fixing the stations, details are located either by radiation or intersection. The characteristic feature of resection is that the point ... of resection are (1)The Two Point Problem, and (2)Three Point Problem.

Give the simplest method of finding the area of zero of a zero circle from manufacturers table.

Description : Give the simplest method of finding the area of zero of a zero circle from manufacturers table.

Last Answer : The area of zero circle can be find out simply by using following formula. A = M x C Where, A = Area of zero circle  M = Multiplier or multiplying constant provided in manufacturers table C = Constant of planimeter provide in manufacturers table

What are the different methods of contouring? Describe any one method along with sketch . Also write the situation where it is suitable

Description : What are the different methods of contouring? Describe any one method along with sketch . Also write the situation where it is suitable

Last Answer : There are two methods of contouring:- 1. Direct Method 2. Indirect Method - a. By squares  b. By cross section  c. By tacheometric Direct method of contouring - In this ... joining these identical coloured pegs, we get the required contours on ground by this direct method of contouring. 

Describe the method of locating contours by square method.

Description : Describe the method of locating contours by square method. 

Last Answer : 1) The method of square is indirect method of locating contours. 2) The method of squares is used where the area to be surveyed is small and not much undulating. 3) The area to be surveyed ... points are written on the respective corners. 6) The contours are then interpolated between them. 

Describe the method of setting out simple curve by using the method of offset from long chord with sketch.

Description : Describe the method of setting out simple curve by using the method of offset from long chord with sketch. 

Last Answer : Given data: Direction of two straights, chainage of point of intersection, radius of curve. Procedure:  1) Set theodolite over B and measure deflection angle Ф  2) Calculate tangent length by ... equal to tangent length.  4) Divide long chord into even number of equal parts.     

The method generally preferred to for contouring an undulating area, is (A) Chain surveying (B) Plane table surveying (C) Tacheometrical surveying (D) Compass surveying

Description : The method generally preferred to for contouring an undulating area, is (A) Chain surveying (B) Plane table surveying (C) Tacheometrical surveying (D) Compass surveying

Last Answer : (C) Tacheometrical surveying

In a solution of the three-point problem in plane table surveying, the converging of error is attained through : (a) Concyclic concept (b) Bessel’s method (c) Triangle of error (d) Tracing paper method

Description : In a solution of the three-point problem in plane table surveying, the converging of error is attained through : (a) Concyclic concept (b) Bessel’s method (c) Triangle of error (d) Tracing paper method

Last Answer : (c) Triangle of error

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

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.

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.

Write the use of Gale’s table.

Description : Write the use of Gale’s table.

Last Answer : Gale’s traverse table is useful to find out independent coordinates of theodolite traverse by applying necessary corrections to consecutive co-ordinates of the same traverse. Further these independent co-ordinates are useful to draw the accurate traverse without linear and angular errors.

To orient a plane table at a point roughly south of the mid-point of two inaccessible conical hill stations and in the plains, a point is selected in line with AB and table is oriented at by bringing ab in line with AB. A ray is then drawn towards and at the table is oriented by back ray method. The orientation so obtained, is (A) Unique and correct (B) Incorrect (C) Manifold and correct (D) Not reliable

Description : To orient a plane table at a point roughly south of the mid-point of two inaccessible conical hill stations and in the plains, a point is selected in line with AB and table is oriented at by bringing ab ... , is (A) Unique and correct (B) Incorrect (C) Manifold and correct (D) Not reliable

Last Answer : (C) Manifold and correct

Explain Orientation of plane table by Back-sighting Method.

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

Last Answer : Ans:- The method of setting up the plane table at each of the successive stations parallel to the position it occupied at the starting station is known as an Orientation. Orientation must be done when ... and bisection of the ranging rod at a are perfect then orientation is said to perfect.  

What is orientation of plane table? State the procedure of any one method of orientation.

Description : What is orientation of plane table? State the procedure of any one method of orientation.

Last Answer : Orientation of plane table: It means placing table in parallel positions at all stations (or at successive station) 1. Orientation using trough compass: Here north direction is marked at first station ... rotated till ranging rod at previous station is exactly bisected. The table is then clamped. 

Explain direct method of contouring.

Description : Explain direct method of contouring.

Last Answer : Direct method of contouring - In this method of contouring, the contours of required reduced level are plotted on ground itself. The procedure of direct method of contouring is as follows. ... identical coloured pegs, we get the required contours on ground by this direct method of contouring. 

Write principle of stadia method.

Description : Write principle of stadia method.

Last Answer : Principle of stadia method: The stadia method is based on the principle that the ratio of the perpendicular to the base is constant in similar isosceles triangles. In figure, let two ... stadia interval factor and the constant (f + d) is known as the additive constant of the instrument

Compare theodolite traversing by included angle method with deflection angle method. Which one is suitable?

Description : Compare theodolite traversing by included angle method with deflection angle method. Which one is suitable?

Last Answer : Sr.No. Included angle method of traversing  Deflection angle method of traversing 1 This method is most suitable for closed traverse. This method is most suitable for open traverse. ... is suitable for long narrow strip like survey of roads, rivers, canals, railways, etc.

State the methods of locating contours and explain direct method.

Description : State the methods of locating contours and explain direct method.

Last Answer : Methods of locating contours :- 1) Direct method 2) Indirect method i) By cross section ii) By Squares (Block Contouring) iii) Tachometric Method Direct method of contouring:- In ... identical coloured pegs, we get the required contours on ground by this direct method of contouring.

Explain the setting of curve by Rankine’s deflection angle method.

Description : Explain the setting of curve by Rankine’s deflection angle method.

Last Answer : Rankine's deflection angle Method:-  1) Set up theodolite at first tangent point, T1 and level it carefully, set the vernier A to 3600 2) bisect the ranging rod at the point of ... . The angle thus obtained will be set on the vernier of the theodolite for setting out the curve.

State the errors eliminated by repetition method.

Description : State the errors eliminated by repetition method. 

Last Answer : The errors eliminated by repetition method are : 1) Errors due to eccentricity of verniers and centers are eliminated by taking the both vernier readings and averaging them. 2) Errors due to ... bisection of object may compensate each other. 5) Errors due to improper levelling can be minimized 

State the procedure of measurement of horizontal angle by repetition method.

Description : State the procedure of measurement of horizontal angle by repetition method. 

Last Answer : The horizontal angle is measured very precisely using method of repetition as follows : 1) Set-up the theodolite over station O and level it properly. 2) Set the vernier A and vernier B at 0°0'0 ... repeat the same procedure. 9) The mean of both angles gives the horizontal angle AOB. 

Explain the procedure of curve setting by method of offsets from long chord

Description : Explain the procedure of curve setting by method of offsets from long chord

Last Answer : Procedure: 1. Divide the long chord into an even number of equal parts say 8,10,12 etc. 2. Set out the offset as calculated from the formula  and obtain the required points on the ... ED, the offset for the right half of the curve will be the same as those on the left half side. 

State the procedure for measuring a horizontal angle by method of repetition.

Description : State the procedure for measuring a horizontal angle by method of repetition.

Last Answer : Procedure : 1. Set up the instrument over Q and level it accurately with the telescope in the normal position. 2. Set the vernier A to 360o. Loosen the lower clamp direct the telescope ... final reading by three. 14. By taking average of both the face, horizontal angle PQR is obtained.

State Direct & indirect method of contouring.Explain tacheometric method.

Description : State Direct & indirect method of contouring.Explain tacheometric method.

Last Answer : Method of contouring are: 1.Direct method 2 Indirect methods which include a)by cross section b)by squares c) tachometric contouring method. Tachometric contouring method. 1.This method ... calculated by tacheometry formulae. 4 The survey is plotted and then contour lines are interpolated. 

Explain the method of repetition to measure horizontal angle using transit theodolite.

Description : Explain the method of repetition to measure horizontal angle using transit theodolite. 

Last Answer : Procedure: 1 Suppose the angle AOB is to be measured by the repetition process. The theodolite is set over O. The instrument is centered and levelled properly.Vernier A is set at 00 and vernier is at 1800 ... 8 The mean of the two angles obtained from two faces gives the actual angle AOB. 

Describe stepwise procedure to prepare the layout of a small building using total station.

Description : Describe stepwise procedure to prepare the layout of a small building using total station.

Last Answer : Layout of small building by using total station: 1. On the plan supplied by an architect, number the column serially from left to right and top to bottom starting from top left ... of setting out by comparing the diagonal distance between the extreme column centres to their calculated values.

Describe the procedure to determine co-ordinates of a station using GPS.

Description : Describe the procedure to determine co-ordinates of a station using GPS. 

Last Answer : The following are some general GPS field survey procedures that should be performed at each station, observation, and/or session on a GPS survey. A. Receiver setup : GPS receiver shall be set up ... is to identify any problem that may exist which can be corrected before returning from the field.  

Describe the use of digital theodolite for measurement of horizontal and vertical angle.

Description : Describe the use of digital theodolite for measurement of horizontal and vertical angle.

Last Answer : I) Procedure for measurement of horizontal angle with digital theodolite: 1) Taking out digital theodolite for box and fix it on tripod over required station. 2) Approximate leveling by leg adjustment and ... and take the reading at B. 9) Difference of two angle gives required vertical angle AOB

Describe the temporary adjustment of digital level.

Description : Describe the temporary adjustment of digital level.

Last Answer : Temporary adjustment of digital level:- 1) Setup stability:- The digital level should be fixed by rotating its screw head on top of tripod stand. Set tripod legs wide apart to increase the stability ... several times if required. 5) Focus the telescope properly to get clear image of cross hairs .

Describe the procedure for setup of total station.

Description : Describe the procedure for setup of total station.

Last Answer : Following steps are followed for the set up of total station 1. Set up the tripod approximately over the station point. 2. Remove the plastic cap from tripod and make tripod nearly level by stretching ... 7.Focusing of object glass. 8.Check the plate level from time to time during measurement .

Describe the procedure to locate grade contour in field

Description : Describe the procedure to locate grade contour in field 

Last Answer : Line joining the point along the same gradient is called contour gradient or grade contour. All the points on a contour have the same elevation. But all the points on a contour gradient do not ... on contour of RL 64. Similarly others points are established to obtain the grade contour on field.

Describe layout of small building by using total station.

Description : Describe layout of small building by using total station. 

Last Answer : Layout of small building by using total station: 1. On the plan supplied by an architect, number the column serially from left to right and top to bottom starting from top left corner ... setting out by comparing the diagonal distance between the extreme column centres to their calculated values. 

Describe the temporary adjustment of theodolite

Description : Describe the temporary adjustment of theodolite

Last Answer : Temporary adjustment of theodolite:- The following operations should be done as temporary adjustments before taking readings on any theodolite. 1. Setting of theodolite on tripod stand - The theodolite ... .e. cross hairs and object) simultaneously focussing of telescope is said to be completed. 

The type of surveying which requires least office work is (A) Tachometry (B) Trigonometrical levelling (C) Plane table surveying (D) Theodolite surveying

Description : The type of surveying which requires least office work is (A) Tachometry (B) Trigonometrical levelling (C) Plane table surveying (D) Theodolite surveying

Last Answer : (C) Plane table surveying

Which of the following methods of plane table surveying is used to locate the position of an inaccessible point? (A) Radiation (B) Intersection (C) Traversing (D) Resection

Description : Which of the following methods of plane table surveying is used to locate the position of an inaccessible point? (A) Radiation (B) Intersection (C) Traversing (D) Resection

Last Answer : (B) Intersection

State the use of alidade in plane table surveying

Description : State the use of alidade in plane table surveying

Last Answer : 1) It is used for sighting the objects to be located.  2) It is used for drawing the rays. 

State the limitations of plane table surveying.

Description : State the limitations of plane table surveying.

Last Answer : 1) It is not suitable for work in wet climate 2) Several accessories are required to be carried hence possibility lost. 3) Replotting of survey work to different scale is difficult in absence of ... ) It is not intended for accurate work. 6) The plane table is essentially a tropical instrument.

In setting up a plane table at any station (A) Levelling is done first (B) Centering is done first (C) Both levelling and centering are done simultaneously (D) Orientation is done first

Description : In setting up a plane table at any station (A) Levelling is done first (B) Centering is done first (C) Both levelling and centering are done simultaneously (D) Orientation is done first

Last Answer : (C) Both levelling and centering are done simultaneously

Orientation of a plane table by solving two point problems is only adopted when (A) Saving of time is a main factor (B) Better accuracy is a main factor (C) Given points are inaccessible (D) None of these

Description : Orientation of a plane table by solving two point problems is only adopted when (A) Saving of time is a main factor (B) Better accuracy is a main factor (C) Given points are inaccessible (D) None of these

Last Answer : (C) Given points are inaccessible

The operation of revolving a plane table about its vertical axis so that all lines on the sheet become parallel to corresponding lines on the ground, is known (A) Levelling (B) Centering (C) Orientation (D) Setting

Description : The operation of revolving a plane table about its vertical axis so that all lines on the sheet become parallel to corresponding lines on the ground, is known (A) Levelling (B) Centering (C) Orientation (D) Setting

Last Answer : (C) Orientation

The operation of resection involves the following steps 1. Rough orientation of the plane table 2. The three lines form a triangle of error 3. Drawing lines back through the three control points 4. Select a point in the triangle of error such that each ray is equally rotated either clockwise or anti clockwise 5. The points obtained by three rays are the correct location. The correct sequence is (A) 1, 3, 2, 4, 5 (B) 1, 2, 3, 4, 5 (C) 1, 4, 3, 2, 5 (D) 1, 3, 2, 4, 5

Description : The operation of resection involves the following steps 1. Rough orientation of the plane table 2. The three lines form a triangle of error 3. Drawing lines back through the three control points 4. Select a point in the triangle of error ... 2, 3, 4, 5 (C) 1, 4, 3, 2, 5 (D) 1, 3, 2, 4, 5

Last Answer : (A) 1, 3, 2, 4, 5

After fixing the plane table to the tripod, the main operations which are needed at each plane table station are (i) Levelling (ii) Orientation (iii) Centering The correct sequence of these operations is (A) (i), (ii), (iii) (B) (i), (iii), (ii) (C) (iii), (i), (ii) (D) (ii), (iii), (i)

Description : After fixing the plane table to the tripod, the main operations which are needed at each plane table station are (i) Levelling (ii) Orientation (iii) Centering The correct sequence of these operations is (A) (i), (ii), (iii) (B) (i), (iii), (ii) (C) (iii), (i), (ii) (D) (ii), (iii), (i)

Last Answer : (B) (i), (iii), (ii)

In setting up a plane table at any station (a) Leveling is done first (b) Centering is done first (c) Both leveling and centering are done simultaneously * (d) Orientation is done first

Description : In setting up a plane table at any station (a) Leveling is done first (b) Centering is done first (c) Both leveling and centering are done simultaneously * (d) Orientation is done first

Last Answer : c) Both leveling and centering are done simultaneously *

Pick up the method of surveying in which field observations and plotting proceed simultaneously from the following (A) Chain surveying (B) Compass surveying (C) Plan table surveying (D) Tacheometric surveying

Description : Pick up the method of surveying in which field observations and plotting proceed simultaneously from the following (A) Chain surveying (B) Compass surveying (C) Plan table surveying (D) Tacheometric surveying

Last Answer : (C) Plan table surveying

Demonstrate the utility of Remote Sensing and GIS applications in Civil Engineering with appropriate examples.

Description : Demonstrate the utility of Remote Sensing and GIS applications in Civil Engineering with appropriate examples. 

Last Answer : Applications of Remote Sensing in Civil Engineering 1) Silting of storage reservoirs harbors etc. - Remote sensing technique that makes use of satellite imagery gives idea about the silting of ... Impact studies 6) Natural Hazard mapping or assessment 7) Water Resources availability.