ML25183A346
| ML25183A346 | |
| Person / Time | |
|---|---|
| Issue date: | 06/30/2025 |
| From: | Jeffrey Poehler NRC/RES/DE |
| To: | |
| JEFF POEHLER 3014158353 | |
| Shared Package | |
| ML25183A340 | List: |
| References | |
| Download: ML25183A346 (1) | |
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Z AA AB AC AD AE AF AG AH AI AJ AK AL AM AN AO AP AQ AR AS Panelist 1 Panelist 2 Panelist 3 Average ImportanceUncertaintyKnowledge Importance UncertaintyKnowledge ImportanceUncertaintyKnowledge Recommendation ID title of recommendation Scope, objectives, and/or topic modifications Score Score Score Rationale Score Score Score Rationale Score Score Score Rationale Importanc e (avg)
Uncertaint y (avg)
Knowled ge (avg) error bars Import Uncert. Know error More research could be used to gain knowledge on a topic expected to be important to safety More research could reduce uncertainty and clarify topic importance More research could improve knowledge but topic not expected to be safety significant Topic expected to have safety significance but likely could be addressed without additional research Topic may have safety significance but sufficient knowledge exists to manage Topic not expected to have safety significance and sufficient knowledge exists H/M/L H/M/L K/PK/UK H/M/L H/M/L K/PK/UK H/M/L H/M/L K/PK/UK CDM-1 Collect operating experience and conduct targeted studies on degradation mechanisms in reinforced concrete, including corrosion, leaching of calcium hydroxide, carbonation, chloride/sulfates penetration, alkali-aggregate reactions, and boric acid attack. Incorporate lessons learned to inform future practices.
H M
K Colleting operating experience (OE) and lessons learned offers valuable insights that inform aging management strategies and support sound decisions for safe long-term operation (LTO).
H L
K This has been developed and implemented in part. The proposed research could be viewed as the low hanging fruit.
Ranking is set accordingly.
M M
PK Reasonable knowledge on individual degradation mechnism exists. Analyze OpE, LL and advance the knowledge for managing and/or mitigating coupled degradation modes.
2.7 1.7 1.3 0.277778 2.6667 1.6667 1.3333 0.277778 1
2 1
1 2
CDM-2 Investigate the synergistic effects of freeze-thaw cycles, chloride-induced corrosion, and exposure to demineralized water on concrete durability.
M M
PK Investigating freeze-thaw cycles combined with chloride corrosion and demineralized water exposure is important to prevent accelerated structural damage, especially in cold or wet environments, supporting safe long-term plant operation, but M
L K
This in part has been developed in part and implemented. The proposed research could be viewed as the low hanging fruit. Ranking is set accordingly.
M M
PK This combination could cause potential degradation; however reasonable knowledge exists and monitoing and aging management methods are available.
2.0 1.7 1.7 0.277778 2.0000 1.6667 1.6817 0.277778 2
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3 2
CDM-3 Design and perform experiments to understand coupled degradation mechanisms and validate findings with field observations and harvested material data.
H M
UK Identifying which coupled degradation mechanisims would trigger safety concerns and validating them with operating experience support decision making of aging management strategies to ensure safe long-term operation (LTO). Very limited data.
H L
PK Doable but definition of independent/ control variables could lead to dependant variables most critical to monitor specfic aging effects.
Could be a demanding endeavor.
H M
PK Collect OpE, LL and use them for improving knowledge, setting up experiments, validating with real data and trend.
3.0 1.7 2.3 0.277778 2.9700 1.6667 2.3333 0.277778 3
CDM-4 Develop generic models to serve as guidance for plant-specific applications.
M M
PK Developing generic models offers useful guidance for broad applications, but applying them to plant-specific application requires further evaluation and adjustment due to varying site conditions and design factors, which can pose significant challenges.
H H
H Ideally this would be desireable but development of "comprehensive" generic models to serve as guidance to plant specific applications would be resource intensive.
The ranking is set accordinly.
M M
PK Generic models can be leveraged and be modified for plant-specific situations. In most cases, plant-specific information are not available to the researchers, that's why the research outcome provides generic and broader knowledge.
2.3 2.3 1.7 0.388889 2.3333 2.3333 1.6517 0.388889 4
CDM-5 Expand predictive knowledge and develop tools to address future degradation scenarios.
(Provided CDM-3 can deliver advamncement of knowledge).
H M
PK Expanding predictive knowledge and developing tools to anticipate emergying or accelerated degradation scenarios for plants 80+ years is highly valuable to ensure LTO.
H M
PK Defining and expanding general "predictive" knowledge would be challlenging. Based on that, to develop future and most likely unknown degradation scenarios wouldbe unpredictable and very resource intensive.
H H
PK Example scenarios could be: (i)
ASR+Carbonation+Corrosion+
ASR; (ii) Water seepage +
leaching +
porosity+corrosion+ASR etc.
3.0 2.3 2.0 0.388889 2.9700 2.3333 2.0000 0.388889 5
CDM-1 CDM-2 CDM-3 CDM-4 CDM-5 1
3 2
2 Importance Knowledge Session 8 - Civil Structures, Concrete and Components - Coupled Degradation Mechanisms (CDM)
High Low Known Unknown