The Determination of the Effective Range and Safe Distance from the Nail Wall under Surface and Subsurface Blast LoadsA. Rasoli, M. Khodaparast*, H.

The development of passive defense systems and the importance of blast load and adoption of necessary measures regarding the effects of blast loading on the design and performance of underground structures, including stabilized excavations using the nailing method, make it necessary to investigate the effect of blasting on performance and deformation of nailed walls. Therefore, in the present study, three-dimensional modeling and nonlinear dynamic analysis of a nailed wall to a depth of 9 meters, under the blast load were investigated using the Coupled Eulerian-Lagrangian method in Abacus software. To model the blast load, TNT explosive was used in different masses on the ground surface and at depths of 2, 4, and 6 meters behind the wall. In this study, while defining the two concepts of safe distance and explosion impact range, the results showed that in the stabilization of the nailed wall under the blast load, the increase in explosive mass causes an increase in the horizontal deformation created at the edge of the excavation wall and the stress created in the nails. Also, the effect of subsurface explosion on the stability of the nailed wall is greater than the surface explosion with the same mass of explosive.