This other kind of definition initially displays the same sub-menu as the Station and Height option. Once the first item of data (station) is entered, the program requests the height and then displays the terrain’s data at the point desired by default. After the first point is thus specified, it requests the Distance from the alignment from the first to the current vertex. When this distance is entered, the program requests its Slope. It then creates the new alignment vector based on the previous one and with the distance set. The program will continue to request distance and slope until it is given a null response. Once the grade line has been defined, the program assumes the alignments and matches them to the parameters of the profile’s orthogonal projection.
It should be remembered that for a distance of less than zero, the slope to be set in the opposite direction to the left and right, implies a change of sign after the slopes (+ Ramp, - Slope). In other words, for distances of less than zero, both a ramp seen from the final point as well as a slope seen from the final point will have to be considered.
Having described the three procedures for defining straight grade line alignments, we should mention that they can be alternatively defined using the three methods, accessing each of them without finally completing the process. Lastly, it is convenient to save the alignments’ status in a separate file using the Export Grade Line option although one may later proceed to the process of matching the vertices.
TcpMDT
