ABSTRACT
Road tunnels in Sweden are designed to prevent progressive collapse under accidental loads. Possible sources of these loads are, for instance, collisions or blast loads due to explosive charges or ignition of vapour clouds. Simplified design methods for accidental blast loads consider vertical and horizontal elements individually by simplified boundary conditions. However, interaction effects are activated during internal explosions. This paper summarizes and extends the discussion from a previous project where interaction effects were studied. Individual walls and the entire frame were analyzed, and their response to a high-intensity blast load was compared. The analyses aimed to study whether interaction effects are favourable or unfavourable and the severity of disregarding them.
