Method for evaluating overall performance of containment vessel of nuclear power plant based on distributed sensing technology

Abstract

The invention relates to the field of safety monitoring of major civil engineering structures and nuclear safety, specifically relates to a method for evaluating the overall performance of a containment vessel of a nuclear power plant based on a distributed sensing technology. The method comprises the following steps: laying sensing optical fibers on the containment vessel; acquiring a true strainvalue and a radial displacement value of a cylinder; obtaining a theoretical strain value and a radial displacement value of the cylinder; evaluating performance of the containment vessel; and judging whether the containment vessel meets an overall strength requirement. The method for evaluating the overall performance of the containment vessel of the nuclear power plant based on the distributedsensing technology can still perform the overall performance evaluation even in an event of a failure of a vibrating wire sensor pre-buried in the containment vessel structure, has innovative points and advantages of multi-area laying, long distance, rich data, and capable of eliminating an accidental error of the local position., can meet the needs of existing pre-buried strain monitoring sensorssupplementation and the needs of upgrading and transformation before the failure, and ensures the long-life operation of the nuclear power plant.

Description

technical field [0001] The invention relates to the fields of safety monitoring of major civil and structural engineering and nuclear safety, in particular to a method for evaluating the overall performance of containment shells of nuclear power plants based on distributed sensing technology. Background technique [0002] Optical fiber sensing technology has many advantages, such as small size, anti-electromagnetic interference, no drift, good durability, and long transmission distance. Among them, distributed sensors are based on the principle of Brillouin scattering, which can perform real-time monitoring of large-scale, long-distance, and distributed strains. It has been gradually applied in the field of structural health monitoring, and it is a good sensor with potential application in long-term health monitoring of civil engineering structures. At present, it has been widely used in tunnels, bridges, pipelines and other structures. [0003] The integrity evaluation of ...

AI Technical Summary

Problems solved by technology

[0003] The integrity evaluation of the traditional containment structure is mainly based on a number of vibrating wire stress gauges embedded in the containment construction stage, and is evaluated and predicted through the containment strength test during daily operation and the containment strength test during the ten-year overhaul compression test. Concrete strain is one of the most important indicators. However, the possibility and severity of embedded vibrating wire sensor failures that cannot be repaired or replaced will increase as the service time increases.

The IAEA (International Atomic Energy Agency) pointed out that "the average failure rate of such sensors in French nuclear power plants is about 2% per year". At present, some nuclear power plants have embedded vibrating wire strain monitoring sensors. The effectiveness of the system is not enough to accurately evaluate the performance and safety status of the containment, which will eventually lead to the fact that the structural performance of the containment during the operation of the nuclear power plant is not under effective monitoring and does not meet the requirements of nuclear safety supervision.

The failure of the embedded sensor is irreversible and cannot be repaired or replaced. At present, domestic nuclear power plants are applying for an extension of 20 years of operation, which puts forward higher requirements for the monitoring of the containment structure performance.

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