Method for evaluating performance of containment based on white light interference sensing technology

Abstract

The invention relates to the field of safety monitoring of major civil and structural engineering and nuclear safety, in particular to a method for evaluating performance of a containment based on a white light interference sensing technology. The method comprises the following steps that sensing optical fiber is laid on the containment; a true strain value and radial displacement value of a cylinder are acquired; a theoretical strain value and radial displacement value of the cylinder are acquired; performance evaluation is carried out on the containment, and it is judged whether or not the containment meets the requirement of the overall strength. The method for evaluating the performance of the containment based on the white light interference sensing technology has the advantages thatthe overall performance evaluation can still be carried out under the situation of the failure of a pre-buried vibration wire sensor of a concrete structure of the containment, multi-area laying, longdistance, high precision, large data volume and visualizability are achieved, the accidental error of a local position can be eliminated, the upgrading and reconstruction needs of an existing pre-buried strain monitoring sensor before supplementing and failure, and guarantee is provided for the operation of long service life of a nuclear power plant.

Description

technical field [0001] The invention relates to the fields of safety monitoring and nuclear safety of major civil and structural engineering, in particular to a containment performance evaluation method based on white light interference sensing technology. Background technique [0002] Optical fiber sensors have many advantages, such as small size, anti-electromagnetic interference, no drift, good durability, and long transmission distance. Among them, white light interferometric sensors are based on the Michelson interference principle, and have the advantages of long-distance transmission and real-time monitoring of overall strain. It has been applied in the field of structural health monitoring and is a good sensor with potential application in long-term health monitoring of civil engineering structures. At present, it has been initially applied in the fields of reinforced concrete corrosion monitoring, concrete freeze-thaw damage monitoring and so on. [0003] The integ...

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 failure of the structural performance of the containment to be under effective monitoring during the operation of the nuclear power plant, which 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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