Two of the most prevalent calculation methods of road projects’ earthworks in terms of robustness and computational easiness are the methods of the average end-area and applicable lengths. The present study, focuses on the second method and specifically, compares the classical calculation approach to a simplified approach.
The classical calculation approach of the applicable lengths computes the earthworks of a cross section (n) by multiplying its surface area with the respective applicable lengths, which is the sum product of 1/4 or 1/2 of the distance with the prior cross section (n-1) and 1/4 or 1/2 of the distance with the following cross section (n+1), depending on whether the prior/following cross section is of the same type (cut or fil) with the section (n). The proposed simplified approach computes the earthworks of a section, by considering that the applicable lengths is always equal to the mean value of the distances with the prior and the following cross section, without checking the type of the prior/following cross section. To validate the performance of the simplified approach the earthworks’ volumes of a number of projects was computed with the classical and simplified approach and the results were compared with the exported results from a road design software where volume measurements were taken every one meter. As a first step towards the validation of the approach, nine projects with different territories were investigated. Then, projects with different slope and standard deviations of the height differences between the road profile and the terrain profile were further investigated. Finally, in 45 road projects with the same horizontal alignment but different longitudinal profile, the earthworks’ volumes were calculated for three different typical cross sections. The results that arouse from each step of the analysis, indicate that both approaches produce very similar results, regardless of the changing parameters.

road project, earthwork volumes, applicable lengths method, mass table