Object: To draw a Profile of a road (L-section) from the obtained level data.
Theory:
Profile leveling is one of the most common applications of running levels and vertical distance measurement for the surveyor. The results are plotted in the form of a profile, which is a drawing that shows a vertical cross-section. Profiles are required for the design and construction of roads, curbs, sidewalks, pipelines, etc. In short, profile leveling refers to the process of determining the elevation of points on the ground at mostly uniform intervals along continuous line.
Instruments required:
Field book, Graph sheets, Pencils, etc.
Procedure:
The procedure mainly consists of two parts i.e. field procedure and plotting the profile.
Field Procedure:
Profile leveling is essentially the same as benchmark leveling, with one basic At each instrument position, where the height of the instrument (H.I) is determined by a back sight rod reading on a benchmark or turning point, several additional foresight readings may be taken on as many points as desired.
These additional readings are called rod shots, and the elevation of all those points is determined by subtracting the rod shot from H. I at that instrument location.
Plotting the profile:
Draw the profile drawing. The profile drawing is basically a graph of elevation/reduced level, plotted on the vertical axis, as a function of stations, plotted on the horizontal axis.
A gridded sheet called profile paper is used to plot the profile data from the field book. All profile drawings must have a proper title block, and both axes must be fully labeled with stations and elevations/reduced levels.
The elevation or elevation scale is typically exaggerated, e. it is ‘stretched’ in comparison to the horizontal scale. For example, the vertical scale might be 10 times larger.
The horizontal line at the bottom of the profile does not necessarily have to start at zero elevation.
The figure below shows a profile drawing:
Result:
The longitudinal sectioning is carried out as specified, and the obtained level data is used to plot the profile on a graph sheet in MS Excel.
Watch Video
Excel:
AutoCAD:
How to draw the center line of road in AutoCAD | How to plot Road center | AutoCAD
