Dynamic Analysis of Twin Tunnel Subjected to Internal Blast Loading

Abstract

The present study deals with three dimensional nonlinear finite element analyses of underground twin tunnels in soil with reinforced concrete (RC) lining subjected to internal blast loading for blast occurring in one tunnel. The blast load has been simulated using coupled Eulerian-Lagrangian (CEL) analysis tool available in finite element software Abaqus/Explicit. Soil mass and RC lining have been modeled using three dimensional eight node reduced integration Lagrangian elements (C3D8R). Beam elements (B31) have been used to model reinforcement of RC lining. A 50 kg TNT charge weight has been used in the analysis. Eight node reduced integration Eulerian elements (EC3D8R) have been used to model the TNT explosive and the surrounding air. Drucker-Prager plasticity model available in Abaqus has been used to simulate strain rate dependent behavior of soil mass. For simulating strain rate dependent behavior of concrete and steel, concrete damaged plasticity and Johnson-Cook plasticity models, available in Abaqus, have been used, respectively. The explosive (TNT) has been modeled using JWL equation-ofstate. Investigations have been performed for studying the deformation of RC lining and surrounding soil mass. Pressure in the RC lining and surrounding soil mass, caused by explosive induced shock wave have also been studied for both tunnels. It is observed that deformation in tunnel away from blast decreases with increasing soil cover in between two tunnels.

Determination of Blast Impact Range and Safe Distance for a Reinforced Concrete Pile Under Blast Loading

“…Bars of 10 mm in diameter spaced 100 mm apart (T10@10cm) were used for shear reinforcement of the piles. The concrete and reinforcements of the piles were modeled using the concrete damage plasticity and Johnson-Cook hardening behavior models, respectively [19]. The properties of the modeled RC piles are shown in Table 4.…”

“…The properties of the modeled RC piles are shown in Table 4. Stress-strain curves for compression and tension and the damage versus compression and tension strain curves are shown in Figure 4 [19]. The stress-strain behavior of the steel reinforcing bars was defined using the Johnson-Cook (J-C) hardening behavior model.…”

Investigation of the Blast-Induced Crack Propagation Behavior in a Material Containing an Unfilled Joint

“…To further reveal the mechanical mechanism of the failure pattern in a jointed rock under blasting, a finite element method (FEM) was used to investigate the propagation of a blast wave. Among the pieces of finite element software, ABAQUS has been commonly used to simulate the stress evolution under impact, blast and other dynamic loadings [29][30][31]. Therefore, the ABAQUS software was used to carry out the numerical simulation in our study.…”

Dynamic Response and Safety Control of Newly Poured Secondary Lining Concrete under Large Section Tunnel Blasting-A Case Study of Longnan Tunnel of Ganshen High-speed Railway

“…Shao [6] and Jiang et al [7] used LS-DYNA software to study the influence of tunnel cut hole blasting on the secondary lining of existing railway tunnels; Kong et al [8] and Wang et al [9] used LS-DYNA software to study the influence of explosion load on the lining structure of subway tunnel. Some scholars use the numerical simulation software LS-DYNA to study the influence of blasting vibration on different types of tunnel lining [10][11][12][13][14][15].…”