ALGORITHM FOR CALCULATING THE TUNNEL PROFILE AREAS

7th International Scientific Conference - SGEM2007, www.sgem.org, SGEM2007 Conference Proceedings/ ISBN: 954-918181-2, June 11-15, 2007

ABSTRACT

Building a tunnel is a very expensive construction task, especially when cutting
a tunnel in inconvenient geological conditions. The tunnel building is made
drastically more expensive by badly executed works on the cutting itself, i.e. the
excavation, and it happens when the areas of excavation cross-sections differ
from the areas of designed profiles. It is therefore very important to monitor,
apart from the direction of tunnel cutting in terms of position and height, also
the areas of cross sections of the excavated tunnel. The monitoring is made by
means of measuring the profile elements at individual station, and they are
used to calculate the areas that are compared with the designed profiles. This
paper describes the procedure of measuring the elements of the excavated
tunnel cross-section and describes the algorithm for calculating the areas of
excavated and designed profiles. Out of all calculated areas of measured and
designed profiles, the volume of over-profile and under-profile for the whole
length of a tunnel are calculated. The example of the measured and designed
profiles of the tunnel “Mala kapela” is presented graphically.

Keywords: Tunnel building, area calculation, cross section, over-profile, underprofile.