Understanding simple difinition contour lines ₪ 3.1 Definitions and terminology

 A longitudinal profile is the representation of a vertical section along the axis of a linear project (road, railway, pipeline, etc..).

The longitudinal profile is supplemented by cross sections which are vertical sections perpendicular to the axis of the project. Their establishment generally allows the calculation of earth movements ( cubatures ) and, for example, makes it possible to define the ideal layout of a project so as to equalize the volumes of excavated earth with the volumes of backfilled earth. (Not always easy!!)

For example, in figure 10.10., a road project is shown as a centerline. The longitudinal profile constitutes a development along its axis on which the natural ground and the project are represented. The cross sections, regularly spaced, are a sectional view which provides the inscription of the road in the relief perpendicular to the axis.