Papers by Keyword: Reliability Method

Abstract: Dam security is the key of concrete high dam. This thesis proposes design flow chart in high arch in service, according to researches of dam brought performance-based design theory. The reliability method is adopted, based concrete behavior of change by strain rate and hold time of load influence in seismic action. In elastic stage, using control total cost formulas get corresponding deformation of arch dam under the minimum total, provided a reference for project.

Abstract: The aim of this paper is to present a new methodology for the evaluation of the statistical proprieties of the response of structures, based on The Finite Element Analysis (FEA) coupled with the Probabilistic Transformation Method (PTM). Uncertainty modelling with random variables motivates the adoption of advanced PTM for reliability analysis to solve problems of mechanical systems. The PTM is readily applicable in the case where the expression between input and output of structures are available in explicit analytical form. However, the situation is much more involved when it is necessary to perform the evaluation of implicit expression between input and output of structures through numerical models. For this we propose technique that combines the FEA software, and the PTM program to evaluate the Probability Density Function (PDF) of the response where the expression between input and output of structures is implicit. This technique is based on the numerical simulations of the FEA and the PTM by making an interface between Finite Element software and Matlab. Some problems of structures are treated in order to demonstrate the applicability of the proposed technique.

Abstract: The integrity of major components in nuclear power plant should be maintained during operation. In order to maintain the integrity of these components, complicated assessment procedures are required including fracture mechanics analysis, etc. The integrity assessment of components has been performed by using conventional deterministic approaches whilst there are lots of uncertainties to carry out a rational evaluation. In this respect, probabilistic integrity assessment is considered as an alternative method for nuclear component evaluation. The objectives of this paper are to develop an integrity assessment system based on probabilistic fracture mechanics and to estimate the failure probability of major nuclear components containing a defect. The integrity assessment system consists of three evaluation modules which are first order reliability method, second order reliability method and crude Monte Carlo simulation method. The developed system has been applied to evaluate failure probabilities of nuclear structural components such as steam generator tube and piping. The evaluation results showed a promising applicability of the probabilistic integrity assessment system.