ML21019A071
| ML21019A071 | |
| Person / Time | |
|---|---|
| Issue date: | 01/21/2021 |
| From: | Hector Rodriguez-Luccioni NRC/NRR/DNRL/NLRP |
| To: | |
| Rodriguez-Luccioni H | |
| References | |
| Download: ML21019A071 (7) | |
Text
Public NRC Meeting License Renewal for 100 years of Plant Operation, Technical Issues for Civil Structures and Concrete A Researchers Point of View Victor E. Saouma url; saouma@colorado.edu University of Colorado, Boulder X-Elastica, LLC Jan 21, 2021 Victor E. Saouma; Univ. of Colorado 100 Years of operation? Concrete Concerns 1/7
Table of Contents 1
A: Should the NRC develop guidance?
2 B: Technical issues 3
C: Approaches Lessons Learned by VES Recommendations
4 Background
Victor E. Saouma; Univ. of Colorado 100 Years of operation? Concrete Concerns 2/7
A: Should the NRC develop guidance?
My guess is that there will be a strong push from industry (and possibly from the NRC) for such an extension.
Short answer: Yes. If the Pentagon has contingency plans to attack Canada, then the NRC should develop properly crafted contingency documents for a 100 years operation, as soon as possible.
Note:
Keep in mind that there is a time lag between scienti"c knowledge and engineering codes.
To the best of my knowledge no other country is making such a bold move, not even for 80 years Let us always keep in mind that those reactors were designed with 40+
year-old technology for 40 years (not 60, 80, let alone 100).
Since then much has been learned about aging, seismic, and safety. We can not ignore those developments.
Victor E. Saouma; Univ. of Colorado 100 Years of operation? Concrete Concerns 3/7
B: Technical issues Containment Internal Structure concrete Chemical Physical Chloride Diffusion Carbonation Time Dependent Radiation Sulfate Attack Delayed Ettringite Formation External Sulfate Attack Shrinkage Creep Temperature Thermal cycles Freeze/Thaw Mechanical Fracture LCF/ILRT Acid Attack Leaching ASR 1.7 2.1 1.4 2.3 1.9 1.6 2.0 2.6 2.9 2.6 2.3 2.3 2.9 Knowledge Succeptibility 1
2 3
0 1
2 3
Knowledge Succeptibility 1
2 3
0 1
2 3
11 9
4b 4a 12 5
3 2
7 6
8 101 Confidence values Symbol size and color is a measure of structural significance, relative to a maximum value of 3 1: Chloride diffusion; 2: Carbonation; 3: AAR; 4a DEF; 4b: External sulfate attach; 5: Acid attack; 6: leaching; 7: Shrinkage; 8: Creep; 9: Thermal cycling; 10: Freeze and thaw; 11: Fracture; 12: Radiation.
Low Medium High Technical issues have been addressed (for 80 years of operations) by NUREG/CR-7153, Vol 4 Expanded Materials Degradation Assessment (EMDA)
Volume 4: Aging of Concrete and Civil Structures (2014)1 Two sites have been affected (as far as I know) by ASR:
Seabrook: Containment building North Anna: Transmission towers Biggest issues (2021) & both cause swelling AAR Containment building Radiation Reactor vessel Within a 100 years operations, likely to be many more.
1I was a member of the panel Victor E. Saouma; Univ. of Colorado 100 Years of operation? Concrete Concerns 4/7
C: Approaches Lessons Learned by VES First, lessons learned from my personal involvement with Crystal River and Seabrook2 NRC has not regulated, but commented on documents submitted by industry Minimal technical input from regulator Absence of well known NRC experts (such as Herman Graves, Dan Naus or Abdul Sheikh)
No panel reviews What is the point in having knowledge (per previous slide) if it is not applied and we remain shackled by 40 years old design codes!
Administrative/bureaucratic considerations prevailed over best possible (and reasonable/achievable) safety.
This paradigm should be avoided in its entirety. This is now an entirely new ball game 2This is relevant as it is indicative as to how the NRC seems to have has addressed technical challenges related to Beyond Design Basis Victor E. Saouma; Univ. of Colorado 100 Years of operation? Concrete Concerns 5/7
C: Approaches Recommendations The NRC should:
1 Safety and not $$ utmost priority 2
Science "rst, Engineering second 3
Develop regulation itself and not subcontract task to industry or EPRI.
4 Convene panel of experts and revisit the 2014 EMDA.
5 Fund and adopt research (laboratory tests and simulation tools) when needed, and results should be implemented in regulations 6
Convene technical panels, perform peer reviews 7
Forget original design codes for operation or aging management, enforce compliance with most recent ones, and prioritize scienti"c knowledge over design codes 8
Tighten Aging Management Program 9
Should be a collaborative effort between Scientists, Engineers, Regulators, &
Utility Companies.
and maintain its worldwide leadership in nuclear safety.
Victor E. Saouma; Univ. of Colorado 100 Years of operation? Concrete Concerns 6/7
=
Background===
1 Saouma
- Hariri-Ardebili Aging, Shaking, and Cracking of Infrastructures xisting struc-ds.
ures, the pre-ines, bridges, eismic), both finite element bilistic meth-assessment.
- e. codes), this n the first oncrete ransient abilistic d, archival Victor Saouma Mohammad Amin Hariri-Ardebili From Mechanics to Concrete Dams and Nuclear Structures Aging, Shaking, and Cracking of Infrastructures RILEM State-of-the-Art Reports Victor E. Saouma Editor Diagnosis &
Prognosis of AAR Affected Structures State-of-the-Art Report of the RILEM Technical Committee 259-ISR an informa business Victor E. Saouma Saouma barcode Numerical Modeling of AAR Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed vestibulum elit at sem mattis molestie. Donec non hendrerit diam. Pellentesque placerat, nisl non volutpat mollis, neque quam suscipit odio, quis pretium lectus lacus nec sapien. Vivamus iaculis, erat eget dapibus pulvinar, purus erat mollis mauris, ut congue sem lectus ac orci. Sed tempor tortor eu mi mattis at interdum lacus vulputate. Vestibulum gravida est vel est vestibulum semper ut eu nunc. Aliquam sit amet turpis dolor, ac eleifend lorem. Integer at tellus nulla, id venenatis lorem. Etiam ut condimentum felis. Morbi et tortor vitae est lobortis rhoncus. Praesent eget facilisis lorem. In hac habitasse platea dictumst. Aliquam sagittis mauris eget massa aliquam eget auctor arcu ultrices. Sed rhoncus faucibus diam, quis porta libero dapibus quis. Sed nibh nisl, viverra eu pretium eget, tincidunt convallis mauris. Donec tortor neque, congue et gravida a, feugiat vitae nulla.
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed vestibulum elit at sem mattis molestie. Donec non hendrerit diam. Pellentesque placerat, nisl non volutpat mollis, neque quam suscipit.
Numerical Modeling of AAR Victor E. Saouma Victor E. Saouma; Univ. of Colorado 100 Years of operation? Concrete Concerns 7/7