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As the population grew, cities expanded rapidly, requiring Super structures for residents to live in, as well as heavy structures such as bridges for faster population access to various locations. Also in big cities, tunnels are needed for various purposes, such as moving facilities, car lanes and subway tunnels, which is one of the concerns of engineers. On the other hand, most of these tunnels are built in cities in the vicinity of heavy structures that deliberately have deep and semi-deep foundations. Tunnel excavation has caused long-term and short-term displacements at the ground surface, which is more pronounced in piles adjacent to the tunnel excavation site. In such a way that the displacements formed in the ground are transferred to the piles and cause axial force in the piles. All these studies on the effects of drilling on adjacent structures and piles are very important in terms of drilling safety factor. Accordingly, in the present study, a three-dimensional analysis has been performed using ABAQUS finite element software. The effects of tunnel drilling with different diameters and locations on the deep foundation in the bridge near the drilling site have been investigated. The results showed that tunnel location, if improperly selected, has destructive effects on pile tip settlements, axial force changes of piles and tunnel surface settlements. Similarly, as the diameter of the tunnel increases, the number of piles in the pile increases sharply when the tunnel is located just below the tunnel site. Also, as the diameter of the tunnel increases, the number of piles in the pile group increases by about 29% when the tunnel is located just below the pile group. When the construction site of the tunnel is located between the group of piles and at a greater depth than the tip of the piles, the amount of settlements changes to a critical state and with increasing the diameter of the tunnel, the rate of subsidence of the pile tip increases by 48.9% and the amount of subsidence Increases by 54%.

Investigation and evaluation of damages to surrounding structures and also estimation of rupture levels by considering the amount of deformations and the amount of adjacent gates are important issues in the nailing system in urban areas. In this research, we tried to evaluate the axial force of the nails and the deformation in concave and convex dams; in sandy and clay soils. In this regard, numerical modeling is carried out using the Abaqus CAE software in the soil environment and parametric studies are carried out for different corner angles in the excavation under the service load. The results of this study indicate the effect of concave cortical deterioration and the damaging effect of the convex corners, which is in contrast to the concave hedge, in gondolas with sandy soil as well as clayey soil. The maximum axial force of the nails in the clay soil is less than that of the sandy soil, which decreases with the approach to the hollow corner. For maximum seating and horizontal displacement of the Goodwall wall, there is also a turning point between the angular angles of 130 ° to 150 °, with a good turnaround. By comparing and analyzing land surface levels and rupture levels, we will find that the maximum level of earth's summation in sandy soils will be the highest level of rupture, and in clay soils, ground-level landings in the location of critical burst surface changes It is noteworthy.

Due to the development of metro lines, always the maintenance of buildings of injuries in urban environments is important, therefore, investigation of the surface settlement of the tunnel is undeniable. Several researchers have yet studied the ground surface settlement. With increasing in number of metro lines, interaction between them will be important. So, in the follow-up to this researches, in this paper the interaction between the tunnels on the surface settlement using numerical modeling software FLAC3D is investigated. For this purpose intersection between metro lines in Tabriz (Line 1, 2 and 3 around of Daneshsara square), that the most important issue is the interaction between metro tunnels in Tabriz city, is considered. In this study, the EPB machine system used for excavation of tunnel. The modellings indicates that passing the line 3 metro tunnels of Tabriz under the line 1 makes a 139.4 % increase in surface settlement. Studies have also shown that passing the line 3 tunnels above the line 2 tunnel makes a 56 % increase in surface settlement.

The need for rapid construction of the tunnel along with the safety of surface structures has increased the use of mechanized tunnel boring machines in the urban environment. In this paper, shield mechanized tunneling is introduced as one of the modern tunneling methods. In the following, the mechanism of operation of the TBM-EPB as the most commonly used boring machine in urban environments, along with the benefits of using this device, and the new technologies in the design of all-section boring machines, are introduced. Considering the importance of surface settlement in urban environments, controlling soil pressure, continuous injection of grout and controlling the volume of excavated materials, is one of the most important ways of preventing surface settlement in tunneling using a mechanized boring machine. In this study, the Plaxis software is used to investigate the effect of cement grout injections between the outer surface of concrete linings and the shield of the machine during tunnel boring operations on the surface settlement.