Given below, some vital terms in Surveying and Leveling :-
Level Surface: It refers to a surface that is normal to the direction of gravity at all points as stated by a plumb line. As for instance, the surface of a still lake can be a level surface.
Since the earth is an oblique spheroid, a level surface should not belong to a plane but should be a cursed one. The distance of each point on a level surface is equal from the center of the earth.
Level Line: A level line belongs to a line that is laid on a level surface. It is normal to the plumb line at all points.
Horizontal Plane: A horizontal plane through a point refers to a plane peripheral to the level surface at the point. It is normal to the direction of gravity at that point.
Horizontal Line: A line that remains at a 90 degree angle to the plumb line and tangent to a level surface is called a horizontal line.
Vertical Plane: A vertical plane belongs to any plane with a vertical line. A vertical line at any point stands for a line normal to the level surface at that point.
A plumb line is an instance of a vertical line.
Datum Surface: A datum or datum surface is the level of a point or the surface relating to which levels of other points or planes are measured.
Published By
Arka Roy
www.constructioncost.co
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