Modeling the Effects of Surface Blast on Underground Structures With or Without Protective Barriers

An underground structure, such as a tunnel or a pipeline, may sustain significant damage due to an explosion occurring on the ground surface. The extent of damage would depend on the material and configuration of the structure, as well as the nature and geometry of the intervening material. An underground structure may be protected by means of a protective barrier, installed directly above the structure. In this paper the results using a compressible barrier, made of polyurethane foam are presented. The effects of surface explosions were studied through a combination of physical model tests and numerical modeling. Reduced-scale (1:70 scale) physical model tests were conducted using a geotechnical centrifuge, where the scaling law for explosions was utilized to model the effects of a large explosion using a relatively small mass of explosives under a high gravitational field (70 g, in this case). The results of the physical model tests were used to calibrate a three-dimensional numerical model in which a fully-coupled Euler-Lagrange solver was utilized to model the explosions. Tunnel configurations with and without protective barriers were studied to assess the mitigation provided by protective barriers. The influence of barrier thickness in reducing the strains induced by an explosion was also studied. It was found that the beneficial effects of a protective barrier increase with increasing barrier thickness only up to a certain thickness. After that, further increase in thickness does not result in additional reductions. Such results can be used in design optimization, while planning protection systems for tunnels.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; References;
  • Pagination: 17p
  • Monograph Title: TRB 93rd Annual Meeting Compendium of Papers

Subject/Index Terms

Filing Info

  • Accession Number: 01515141
  • Record Type: Publication
  • Report/Paper Numbers: 14-1039
  • Files: TRIS, TRB, ATRI
  • Created Date: Jan 27 2014 2:24PM