RELIABILITY ANALYSIS OF PRESTRESSED CONCRETE CONTAINMENT VESSEL UNDER ACCIDENTAL INTERNAL PRESSURE

The reliability of prestressed concrete containment vessels (PCCVs) subjected to the accidental internal pressures is analyzed. The analysis procedure is based on Monte Carlo finite element (FE) simulation. On the one hand, according to the probability conservation principle, the actual probability distribution of the response is characterized by the finite number of samples; on the other hand, the FE analysis combines the multi-layered shell element, the concrete softened damage constitution, and the secant stiffness algorithm in one framework to simulate the nonlinear behavior of the PCCV accurately and efficiently. Finally, the PCCV tested at Sandia National Laboratories (SNL) is studied. The comparison of the simulated displacements with the test ones illustrates that the FE model and parameters are basically reasonable. Considering the material parameters as random variables and the global strain as the failure indicator, the probability distribution of the response is obtained by 200 FE samples, and the curve of the failure probability with the internal pressure is obtained. The results show that, the simulated failure probability reaches 72.03% and 68.78% under the functional failure and structural failure internal pressures got in the test, respectively. This is consistent with the test results.