The effect of height in vaulted tunnels on the stability parameters

Hassan Ahmadi٫ Vahid Hosseinitoudeshki, Seyyed Amir Hossein Beheshti

This paper presents the effect of height of vaulted tunnels on the stability parameters such as surface settlement, displacement and yielded elements around tunnels. This effect has been investigated in tunnels with different upper arches. Numerical analysis is done by a 2D finite element program with software Phase2, whereby vaulted tunnels are modeled with different upper arches and with widths of 4, 6, 8 and 10 meters and the heights of 3, 5 and 7 meters. The results of the evaluations show that by decreasing the height of tunnels, the stability parameters have improved for all the radius of tunnel arch. Furthermore, variations of the surface settlement, displacement and yielded elements around tunnels has reduced when width of tunnel become larger from radius of tunnel arch.