Prestress load distribution modeling for containment digital twin model

Abstract

This paper examines the prestress load distribution in the ducts of the prestressing tendons of a VVER-type nuclear reactor containment. It introduces a method for distributing the simplified linear load from the prestressing cable onto the surface area of the duct. Furthermore, a procedure for applying this calculation to a detailed numerical 3D model of a containment segment is described. This method can be implemented into computational software, such as OOFEM, to incorporate this more accurately defined load into a comprehensive stress analysis of the segment. Realistic definition of load distribution from prestressing tendons on the surface of the ducts is critical for identifying potential deviations from a uniform prestress distribution within the containment wall. This, in turn, facilitates assessments such as evaluating the extension of the structure’s service life.