Influence of Tunnel Excavation on Tower Foundation Settlement Constructed on Sandy Soil
- PDF / 1,125,205 Bytes
- 13 Pages / 439.37 x 666.142 pts Page_size
- 15 Downloads / 184 Views
Influence of Tunnel Excavation on Tower Foundation Settlement Constructed on Sandy Soil Hassan Obaid Abbas 1 Accepted: 2 June 2020/ # Springer Science+Business Media, LLC, part of Springer Nature 2020
Abstract Tunnel excavation below or alongside towers will be affected on stability and performance of towers because of soil movement and stress distribution changes around and below towers. A finite element model using program Plaxis 3d is carried out to investigate the settlement that occurs in the tower foundation as a result of advancement of tunnel in sandy soil. Mohr-Coulomb model is used to idealize sandy soil while linear elastic model used for idealizing concrete in tunnel lining and tower foundation. Many parameters have been investigated such as influence of vertical and horizontal distance from tower foundation and tunnel location on stability of tower during tunnel excavation. The results showed that the direction of wind load is affected by tunnel excavation direction, if the direction is the same direction tunneling and wind load leads to higher foundation tower differential settlement than in transverse direction. The location of tunnel in lateral direction (x) must be at least 2.5D from the centerline of the tower foundation and in vertical direction (y) must be at least 3D from base level of tower foundation to ensure stability of tower frame. Keywords Tower . Sand soil . Tunneling . Settlement . Finite element
1 Introduction Tunneling is a type of fields of civil engineering that has a long history throughout which they have developed into the structures we know them as today. Tunnel boring machine (TBM) tunneling is the famous method in modern times. This method affects the shape of profile and the primary tunnel lining. Due to the fast growth of the population and fast industrial activity, it is necessary to construct infrastructures such as tunnels in this area which provide large facilities (transportation, tower line, etc). For
* Hassan Obaid Abbas [email protected]
1
Department of Civil Engineering, Engineering College, Diyala University, Baqubah, Al-Khalis, Iraq
Transportation Infrastructure Geotechnology
high-rise towers supported by shallow foundations, the tunnel construction induces ground movements, which in turn affect the settlement of the existing structures in addition to the bearing capacity. It is possible to develop and analyze tunnel behavior during construction by using finite element method. Several researchers adopted this procedure such as (Fattah et al. 2012; Mazek 2014; Waad et al. 2019; Yoo 2013). These numerical simulations of shield-driving tunneling processes have been achieved for having a better understanding of the excavation process, including the deformation and in soil stress during the construction stages. The influence of these stages includes the effect of TBM progress, which modifies the structural and geotechnical behavior of the tunnel. The TBM-induced ground surface settlement in the beginning of the excavation is about 46% of the total settlement
Data Loading...
