Question

5. What is the difference between "gradeline" and "groundline" of a highway? In which step of Highway Design we use them?? 6.Define Vertical Profile of a highway using a simple sketch.

Answer 1

lire Grade >> Origin grounds round line PROFILE VIEW Grade line is a line or slope used as a longitudanal reference for a highway. These are inclinations with the horizontal of the road which are expressed by stating the slope. In the figure shown above, the dark solid lines represent the grade lines. They are regular and smooth lines, just as the top of the roadway will be when finished being built. Ground line of a highway the original ground surface as shown in the profile view. The ground line is represented by a dashed line and is very irregular since the original ground is irregular (or bumpy before construction starts. represents

In which step of highway design we use them? Geometric design of a highway deals with the following steps :- (a) cross-section elements (6) Sight distance considerations (c) Horizontal allignment details for Vertical allignment details (e) Intersection elements. Out of the above Grade line and ground line of highway belongs to the vertical allignment step. Vertical allignment is the elevation (or profile of the centre line of the road. Vertical allignment consists of grades and vertical curves.