The soil environment has generally been under the pressure of natural stresses. Any disturbance such as tunnel excavation alters this situation, squeezes the tunnel passage and causes displacements in layers of soil. These displacements appear as settlements on ground surface which in some cases are significant. In this study, the behavior of soil environment under the effect of tunnel excavation was investigated. First by reviewing previous research results and reported experiences, the subject was shown to be significant. Then, the deformation of soil environment, affected by construction of metro tunnels in Isfahan was thoroughly studied, using Flac 3D and Plaxis 3D Tunnel software . By comparing the calculation results with field measurements, the reliability, accuracy and performance of the method and the software were assessed. The analyses showed the importance of different parameters affecting the settlement of ground surface due to tunnel excavation.The software results and field measurements were in agreement. Therefore, it was concluded that the settlements obtained from the software were reliable for the case of heterogeneous and anisotropic soil. Keywords: natural stresses, Settlement, excavation, metro tunnel
