Safety concept for an HTR liner design for combined stress and strain-controlled load

The liner of a high-temperature reactor is strained by the concrete deformation and the temperature difference between the liner and the concrete. This is a strain-controlled compression load. At some points of the liner loads from closures or components must be transfered through the liner into the concrete. These loads originate from internal pressure, gravity, earthquake etc. and are stress-controlled loads. At these points the liner is loaded by a combination of strain and stress-controlled loads. For the liner dimensioning there are regulations for strain or stress controlled loads, which could not be used in an acceptable way for a combination of strain and stress-controlled load. In this contribution a concept for the dimensioning of liner parts exposed to combined strain and stress-controlled loads is presented. This concept is based on the safety theory. It is practicable with only little additional computation effort. (orig.)