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PhD in Civil Engineering – Assistant Professor, Imam Hossein (AS) University, Tehran
Abstract
With the development of excavation methods in various types of environments, we face many challenges. One of these challenges is excavation in soils such as loose, soft, and cohesionless soils. The use of pre-reinforcement systems is an appropriate method to improve the ground before excavation begins. To properly understand the performance of the pre-reinforcement method, numerical modeling can be utilized. This research studies and investigates the umbrella pre-reinforcement system and grouting. After conducting geological studies in the region and identifying different ground units, the umbrella-arch pre-reinforcement method combined with grouting can be used to reinforce the section of the tunnel that is to be excavated in soft and loose soils. After improving the ground, excavation is carried out. Therefore, the pre-reinforcement system designed for soil environments has been modeled using PLAXIS software. In this method, in addition to numerical modeling, the geometric parameters such as the installation angle and the spacing between forepoling tubes have been investigated, considering the grouting radius. The evaluation criteria in this method are the stability of the tunnel after excavation and the amount of tunnel crown displacement. The optimal parameters are a length of 4 meters, an angle of 15 degrees, and a spacing of 80 centimeters.
Sadeghi, S., Mahdavi Sefat, E., Keyqabadi, M. H., & Mousavizadeh, M. H. (2026). Numerical study of variables affecting tunnel stability during the operation of the four-pole umbrella system (Tehran Metro Line 3). Civil Engineering and new Technologies, 7(7), -.
MLA
Saeid Sadeghi; Ehsan Mahdavi Sefat; Mohammad Hossein Keyqabadi; Mohammad Hussein Mousavizadeh. "Numerical study of variables affecting tunnel stability during the operation of the four-pole umbrella system (Tehran Metro Line 3)", Civil Engineering and new Technologies, 7, 7, 2026, -.
HARVARD
Sadeghi, S., Mahdavi Sefat, E., Keyqabadi, M. H., Mousavizadeh, M. H. (2026). 'Numerical study of variables affecting tunnel stability during the operation of the four-pole umbrella system (Tehran Metro Line 3)', Civil Engineering and new Technologies, 7(7), pp. -.
VANCOUVER
Sadeghi, S., Mahdavi Sefat, E., Keyqabadi, M. H., Mousavizadeh, M. H. Numerical study of variables affecting tunnel stability during the operation of the four-pole umbrella system (Tehran Metro Line 3). Civil Engineering and new Technologies, 2026; 7(7): -.
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