Ultimate analysis of PWR prestressed concrete containment under long-term prestressing loss

Numerical analyses are carried out by using the Abaqus finite element program to predict the ultimate pressure capacity and the failure mode of the PWR prestressed concrete containment at Maanshan Nuclear Power Plant, Taiwan, R.O.C. under long term prestressing loss. Material nonlinearity such as concrete cracking, tension stiffening, shear retention, concrete plasticity, yielding of prestressing tendon, yielding of steel reinforcing bar, yielding of liner plate and relaxation of prestressing tendon are all simulated with proper constitutive models. The results of the numerical analysis show that after the 40 years of service, the prestresses in the prestressing tendons would lose about 19% of their initial values. However, under long term prestressing loss, the ultimate pressure capacity of the containment is still higher than the design pressure 482 kPa by 58%.