Assessment of Grouting Effect on Resistance of Underground Spaces Against Blast Loading

Shelters and underground spaces are among the options to come out from the crisis situation in natural and military disasters. In recent years, from the passive defense viewpoint, buried structures have been considered as safe structures against the air and missile attacks. From this perspective, these structures are a part of the main facilities in peacetime and are important factors to save lives in the event of a natural disaster and during the wars. In this study, the effects of grouting around a tunnel to reduce the impact of blast loads on the tunnel structure is evaluated by the numerical modeling software FLAC 2D, in a part of line 7 of the Tehran subway. Intended specifications for the soil around the tunnel, are the results of uniaxial compression tests conducted on some soil samples made from the Tehran alluvial type C. Finally by carrying out an interpolation in the MATLAB software, two equations have been derived to predict displacement and stresses of the tunnel lining (due to the various parameters of the soil, tunnel and bomb) in order to use in the initial stages of tunnel designing for this purpose.