Title Page
ABSTRACT
Contents
1. Introduction 14
Research Background 14
1.1. Defects of Nuclear Power Plant Containment Building and Different Type of Defects 18
1.2. Various NDT methods 23
1.3. Why would a nuclear power plant containment building need an IRT? 26
1.4. Theory of Heat Transfer 28
1.5. Infrared Thermography 29
1.5.1. Theory of Temperature Measurement 29
1.5.2. IRT Application 33
1.5.3. Emissivity 35
1.5.4. Passive and Active Thermography 37
2. FUNDAMENTAL 39
2.1. Characteristics Observed when using IRT for Concrete Structure Detection 39
2.2. Mechanism of IRT in Concrete Structures 40
2.3. Environments Factors 42
3. EXPERIMENT 47
3.1. Preparation of Testing Specimen 47
3.2. Experimental Set-up 48
3.3. Methods of the Test 51
4. RESULTS AND DISCUSSION 53
4.1. Thermal Image Changes During the Heating and Cooling Process 53
4.2. Consequence of Atmospheric Temperature Change on the Thermal Contrast 57
4.3. Consequence of Relative Humidity Change on the Thermal Contrast 60
5. CONCLUSIONS AND FUTURE WORK 64
REFERENCES 66
OUTCOMES OF RESEARCH 73
Table 1. Defects in Containment Buildings at Domestic Nuclear Power Plants 19
Table 2. Table of emissivity 36
Table 3. Thermal properties of the specimen 47
Table 4. Profile based on crack type and size 47
Table 5. FLIR SC600sc specification 49
Table 6. Condition of the Test Environment 53
Figure. 1. Deterioration of concrete structures 15
Figure. 2. Shin Kori Nuclear Power Plant Unit 3, APR1400 model 18
Figure. 3. Defect of the containment Building Hanbit Unit 4 with (a) Defects less than 8 cm, (b) Defects greater than 20 cm, and (c) Hanul Unit 1 21
Figure. 4. Types and shapes of defects: (a) Crack; (b) Blisters; (c) Leakage; (d) Scaling; (e) Spalling; (f) Delamination 23
Figure. 5. Various NDT methods: (a) Hammer sounding; (b) Chain drag; (c) Visual inspection; (d) Impact echo; (e) Ground penetrating radar; (f) Infrared Thermography 25
Figure. 6. Visible and thermal mapping images 27
Figure. 7. The Electromagnetic Spectrum 30
Figure. 8. The fundamental operation of IR camera in capturing radiation 32
Figure. 9. Application of IRT: (a) Inspection of Photovoltaic Installations[37]; (b) Inspection of mechanical assemblies(motors)[38]; (c) Human and medical[39]; (d)... 35
Figure. 10. Passive and active thermography 38
Figure. 11. Thermal contrast generation due to defect: (a) Daytime heating cycle diagram; (b) Nighttime cooling cycle diagram; (c) Daily heating and cooling cycle at... 42
Figure. 12. Shape of the specimen 48
Figure. 13. Controlled surrounding environment condition system 50
Figure. 14. Schematic of the experimental environment 50
Figure. 15. Changes in the thermal images: (a) Initial heating; (b) After 15 min heating; (c) After 30 min heating; (d) After 15 min cooling; (e) After 30 min cooling;... 54
Figure. 16. A method for determining and quantifying thermal contrast 55
Figure. 17. (a) Mean Temperature over the defects; (b) Mean thermal contrast over the Defects, calculated over a 60-minute period encompassing both heating and... 56
Figure. 18. Changes in thermal contrast for each condition over time (a) Condition 1, (b) Condition 2, (c) Condition 3, (d) Condition 4 58
Figure. 19. Relationship between thermal contrast and atmospheric temperature 60
Figure. 20. Changes in thermal contrast for each condition over time (a) condition 5, (b) condition 6, (c) condition 7, (d) condition 8 61
Figure. 21. Changes in thermal contrast according to conditions during the cooling process (after 20 minutes) (a) condition 1,2,3,4 (b) condition 5,6,7,8 62
Figure. 22. Relationship between Maximum Thermal Contrast and Relative Humidity 63