Alireza Talebinejad - Graduated, Tehran University, Dept. of Mining Engineering, Tehran, Iran
Hamid Chakeri - Phd student, Hacettepe University, Dept. of Mining Engineering, Beytepe, ۰۶۸۰۰ Ankara, Turkey
Mahdi Moosavi - Associate Professor, Tehran University, Dept. of Mining Engineering, Tehran, Iran
Bahtiyar Ünver - Professor, Hacettepe University, Dept. of Mining Engineering, Beytepe, ۰۶۸۰۰ Ankara, Turkey

In recent decades, metro tunnels are increasingly being excavated in Tehran. In these tunnel excavations, it is important to control surface settlements observed during and after tunneling excavation. Some empirical relations exist between shield tunnel characteristics and surface deformations. Also, 2-D and 3-D numerical analyses have been applied to such tunneling problems. This paper reports the results of a study carried out to estimate the values of the surface settlements induced by tunneling (with EPB) of the new extension of Tehran metro (line7). It is aimed at investigating the effect of face pressure on surface settlements during excavation by using empirical formulations and numerical modeling. Due to the structural features and geology of the area, finite difference method was selected and FLAC3D software was used for numerical modeling. The results obtained from the numerical and empirical analyses show that face pressure is very effective on controlling the surface settlement. The results are presented in the paper and provisions for reducing the settlement are discussed.

Earth pressure, Surface settlement, Empirical methods, FLAC 3D