There is no reference to plastic constraint per se but section 2.2.2 assumes plastic constraint in its analysis of the applicability of the Tresca and von Mises criteria to failure of brazed joints. For instance on page 34 he writes
"Even in such a ductile material as pure silver, the level of constraint is so high that hydrostatic stress is very close to the axial one, which means that the values of the principal stresses are very similar."