Decohesive carrying capacity in thermal stress problems

The present paper gives some examples of occurrence of decohesive carrying capacity as a result of purely thermal loadings or radiation. At first some simple statically indeterminate bar systems are analyzed; if the stress distribution is non-homogeneous, then -as a rule-decohesive carrying capacity is achieved before full plastification. The dependence of decohesion on the assumed stress-strain diagram is examined in detail. Further examples are connected with the disks subject to heating, with one boundary condition prescribed in displacements. The results depend essentially on the Poisson's ratio, whereas the limit carrying capacity is independent of this material constant. Finally a comparison of the behavior of disks and of thick-walled tubes is given. The results of some simple experiments are reported too. The considered purely mathematical criterion of decohesive carrying capacity may be particularly useful in these cases of purely thermal loadings, giving a certain simple estimation of admissible limits of such loadings