Based on the existing limited test data, it is possible to set up an approximate constitutive model for creep and shrinkage at temperatures above 100°C, up to about 400°C. The model presented here describes the effect of various constant temperatures on the creep rate and the rate of aging, similar effects of the specific water content, the creep increase caused by simultaneous changes in moisture content, the thermal volume changes as well as the volume changes caused by changes in moisture content (drying shrinkage or thermal shrinkage), and the effect of pore pressure produced by heating. Generalizations to time-variable stresses and multiaxial stresses are also given. The model should allow more realistic analysis of nuclear reactor vessels and containments for accident situations, of concrete structures subjected to fire, of vessels for coal gassification or liquefaction, etc.
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Nuclear Energy and Engineering
- General Materials Science
- Safety, Risk, Reliability and Quality
- Waste Management and Disposal
- Mechanical Engineering