µTTCN - an approach to continuous signals in TTCN-3.

A prestressed concrete pressure-containment vessel having one or more cavities within its external shell. The cavities, whether cylindrical or other shape, are totally contained by prestressing tendons, which apply forces to contain various pressures within the structure. By permitting and actually inducing controlled cracking of the vessel in the outer portions of the thick shell wall, one embodiment of a pressure-containment vessel relieves stresses and enhances resistance to very high internal pressures and to stresses due to high internal temperatures and steep temperature gradients.