Evaluation method for structural integrity assessment in core disruptive accident of fast reactor

The paper focuses on the generic aspects of the main structural integrity issues in the liquid-sodium-cooled fast reactor. The choice of sodium as a coolant has important consequences for the deformation and failure process in the materials used for the main plant components. For example, its high boiling point means that the prim ary and secondary circuit containment operates at ambient pressure and the system loading is dominated by thermal stress. The resultant low primary stresses make leak-before-break a viable integrity criterion for all sodium boundary components. Sodium coolant operates at comparatively high temperatures and this, together with the good heat-transfer properties, means that thermal fatigue and creep are of concern, particularly in the hotter parts of the plant. A third factor concerns the steam generators, where the integrity of the sodium—water boundary is particularly important. The paper will consider the failure processes that must be addressed in relation to these conditions and the development of the integrity assessment arguments.

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Study on method for assessment of the physical structure integrity in Chagan lake in China based on remote sensing

Water Science & Technology ◽

10.2166/wst.2014.405 ◽

2014 ◽

Vol 70 (9) ◽

pp. 1510-1518

Author(s):

Bo-lin Fu ◽

Ying Li ◽

Bai Zhang ◽

Bai-shu Yin ◽

Hong-lei Zhu ◽

...

Keyword(s):

Remote Sensing ◽

Evaluation System ◽

Evaluation Method ◽

Structural Integrity ◽

Physical Structure ◽

Gis Technology ◽

Shoreline Development ◽

Atrophy Rate ◽

Integrity Assessment ◽

Chagan Lake

This paper, taking Chagan lake as the study area, uses and improves MWR V1.0 (Rivers (Lake) Health Assessment Indicators, Standards and Methods V1.0) relating to the theory and method of physical structure integrity assessment. A 500 m × 1000 m grid on the lakeshore zone is a basic evaluation unit, and then a lakeshore physical structural integrity evaluation system using remote sensing (RS) and geographic information system (GIS) technology is established, which contains a target layer, criterion layer and indicator layer. The criterion layer consists of lakeshore condition, shoreline development rate and lake atrophy rate, and the index layer is composed of slope, vegetation cover rate and water level change rate, and another eight indicators. The results showed that for the 23 monitoring points in Chagan lake and the 15 monitoring points in Xinmiao lake, the evaluation results based on RS were 0.60–0.74 and 0.35–0.52, respectively, and the field evaluation results were 0.64–0.77 and 0.35–0.55, respectively. The evaluation results of the two methods consistently indicated that the physical structure of the lakeshore of Chagan lake was healthy and the Xinmiao's lakeshore was sub-health. On this basis, a piecewise evaluation method of physical structure integrity based on the division of the nature reserve function was proposed in this paper.

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