STUDY OF SHOCK IMPEDANCE EFFECTS IN A ROUGH WALLED TUNNEL.

Abstract

The paper deals with the problem of protecting deep underground installations from damage when surface nuclear explosions occur near their tunnel entries. The physical phenomena that occur when an air of long duration (i.e., one caused by a nuclear explosion) passes over the entrance to a tunnel are analyzed. The initial pressure of the shock wave which is subsequently driven down the tunnel is determined, and five sequentially related impedance mechanisms are postulated as controlling the propagation down a roughwalled tunnel. These are entry diffraction, buildup, turbulent choke, wall roughness and feedback. Laboratory and limited field tests confirm the theory for all five impedance mechanisms. But definite experiments at 1000 + psi or at the level of nuclear explosions have not been performed. Suggestions are made for determining the site and design of tunnels and for the control and decoupling of underground explosions. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1969
Accession Number
AD0684790

Entities

People

  • P. B. Porzel

Organizations

  • Institute for Defense Analyses

Tags

DTIC Thesaurus Topics

  • Decoupling
  • Diffraction
  • Explosions
  • Feedback
  • Field Tests
  • Impedance
  • Nuclear Explosions
  • Roughness
  • Shock
  • Shock Waves
  • Underground Explosions
  • Waves

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Explosive Engineering.
  • Fluid Dynamics.