As heat is added, the gaseous products will raise the pressure until the casing can no longer contain it. At that point the casing will burst and the gasses will rapidly expand. The casing will break up into fragments which will be propelled outward at great speed. Warheads are usually designed to maximize one of these effects. Fragments tend to be lethal to a greater range than the blast effects, but it depends on the particular target.
Aircraft are particularly vulnerable to fragment damage as are personnel.
On the other hand, buildings can only be brought down by extensive blast effects. We now turn to a detailed account of each type. The rapid expansion of the gaseous products after the casing has burst creates a shock wave. The shock wave is an acoustic wave like ordinary sound, but of limited duration and great energy. Recall that the energy of the acoustic wave was a function of the amplitude, or peak pressure.