# Three Point Problem In Plane Table Surveying Pdf

Now it is required to establish a station at P. Irrelevant details get omitted in the field itself. At this position the table is said to be perfectly oriented.

The north line is marked on the righthand top corner, the Table is then clamped. It is then leveled, oriented by back sighting and clamped. Visibility Others can see my Clipboard. The triangle is eliminated in such a way that the rays Aa, Bb and Cc finally meet at a point p. This method is inaccurate in the since that the results are likely to be affected by the local attraction.

Plane Table Surveying - Plane table is a graphical methodof surveying in which the field work and the plotting is done simultaneously. Equipments and Accessories for Plane Tabling The following instruments are used in plane table surveying.

This point represents the position of the station P on the sheet. This would represent the exact position of the required station A. The operation is known as centering the plane table.

By repeatedly turning the table clockwise or anticlockwise. While establishing magnetic north on the paper using trough compass, things causing local attraction shall be kept away of the table.

The north line is marked on the right-hand top corner of the sheet. If the traverse to be plotted is a closed traverse, the foresight from the terminating station should pass through the first station. The board is then fixed in position by clamps.

It is leveled, centered and oriented by bisecting the ranging rod at B. Now the rays Aa, Bb and Cc are drawn. This table is directly placed at the required position. Explain the principle of plane table survey. Let C be the instrument station to be located on the plan.

Suppose this ray intersects the previous ray at a point P. With the alidade touching a, the point B is bisected and a ray is drawn. It is leveled and centered so that a point a on the sheet is just over the station A. To check the accuracy of the plane table traverse, a few check lines are taken by sighting back to some preceding station.

## Civil Engineering Surveying Important MCQ PDF - All Exam Review

Here distances are generally measured by tachometric method and surveying work has to be performed with great care. Checking is important and thus done by taking third sight from another station. Show related SlideShares at end. It is then oriented by backsighting the ranging rod at A.

The board is then clamped in this position. Now it is required to fix the position of P on the sheet by the intersection of rays, drawn from A and B. Tech civil at student Follow. Then the station A is marked on the ground.

Give advantages and disadvantages of plane table survey. Give limitations of plane table survey. Thus, when a plane table is properly oriented, the lines on the board are parallel to the lines on ground which they represent.

The tripod may be made to fold for convenience of transportation. Successfully reported this slideshow. Explain the procedure of plain table survey.

Explain the following methods of plane tabling. List of methods of plane table survey and explain any one.

## Plane Table Surveying PPt

Now customize the name of a clipboard to store your clips. The Plane table should be clamped after centering and leveling. The horizontal distances are then measured and scaled off on the corresponding radial lines to mark their positions on the drawing.

Then, how to master the art of selling anything pdf by perfectly bisecting these three well-defined points. These three rays must meet at a point p which is the required point on the map.

This method of survey requires no field book. Thus, this method is preferred in small scale survey and for mountainous regions. Let us select two points A and B on the ground. Are you sure you want to Yes No. The table should be rotated at the time of orientation.

The table is leveled by placing the level on the board in two positions at right angles and getting the bubble central in both directions. The table is then clamped.

The table can revolved about its vertical axis and can be clamped in any position, when necessary. The distance is measured and plotted to any suitable scale. You just clipped your first slide!

It is leveled and oriented by back sighting. If you continue browsing the site, you agree to the use of cookies on this website. The first survey station and the scale of the map shall be so chosen that the entire area can be plotted on the paper.

## Plane Table Survey

With the alidade touching p, the point P is bisected and a ray is drawn. Alidade - a plane alidade consists of a metallic rule with a fine beveled edge called the fiduucial edge. It is required to locate a station at P.