ML120440284

Public Meeting Construction Experiences - Evaluate Impact of Concrete Degradation

ML120440284
Person / Time
Site:	Davis Besse, Seabrook, Crystal River
Issue date:	02/16/2012
From:	Jardaneh M, Alfred Issa NRC/NRO/DCIP/CITB, NRC/NRO/DCIP/CAEB
To:
Jardaneh M., NRO/DCIP/CCIB/CIT, 415-2753
References
Download: ML120440284 (14)

Text

Collect Screen Evaluate Apply Issue Generic Domestic Communications Events

• Collect Collect for Assess impacts p on Screen for Trending Licensing Programs applicability *Communicate to New to impacted Reactors NRC staff Assess impact on Inspection Programs

• Evaluate Lessons International Learned Events Rule Making/ Long Term Research 2

Construction of nuclear installations include significant concrete activities.

Review of domestic and international experience suggests that concrete quality is still an issue.

3

Include:

Pressure retaining / containment / shielding; Housing of structures, systems and components (SSCs);

Structural support for SSCs; Protection of SSCs from natural disasters such as earthquakes, tornadoes and hurricanes; Protection of SSCs from internally and externally generated missiles; Separation and protection of redundant SSCs from the effects of single failures.

4

Varies based on several factors such as:

The functions of the impacted structure and the associated SSCs; The type of defect; The time of discovery : more significant for catastrophic self revealing failures; less significant for slow and progressive failures detected as part of normal monitoring; The design margin; The corrective actions planned or taken.

5

Include:

Latent design defects due to inadequate structural design, improper waterproofing, inattention to details and improper design changes; Latent construction defects caused by poor practices and negligence; g g Improper or inadequate maintenance; Environmental stressors; Beyond design bases accidents.

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NUREG-1055 covers among other things, historical concrete issues; NUREG/CR-6927 focuses on concrete degradation mechanisms and includes a comprehensive list of previous concrete problems at various operating nuclear plants; p  ;

IN 2008-17 lists recent concrete issues at nuclear facilities both domestic and international; IN 2011-20 discusses concrete degradation by Alkali-silica Reaction.

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Alkali-Silica Reaction (ASR) at Seabrook.

Containment Delamination at Crystal River Shield Building Cracking at Davis-Besse 8

Seabrook identified ASR in Control Building/Electrical Building (and below-grade structures) in summer of 2009 during license renewal walkdowns; Standards used for testing during original construction may not accurately predict ASR. Additional tests (ASTM 1260 and 1293) are now recommended; ASR was also discovered in nuclear plants in Japan and Canada.

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On October 6, 2009 and again on March 15, 2011, the concrete containment at Crystal River 3 delaminated.

On October 10, 2011, Davis-Besse discovered cracks in the Shield Building wall.

10

The NRC has issued many publications that address the prevention or minimization of concrete issues; Combined License (COL) applicants/holders should evaluate the available operating and construction experience to prevent similar problems; The staff continues to monitor and evaluate new developments for additional lessons learned.

11

Use ConE insights to inform concrete inspections using Inspection Procedures IP-65001.01, Inspection of ITAAC-Related Foundations & Buildings, IP-65001.02, Inspection of ITAAC-Related Installation of Structural Concrete and IP-35007, Quality Assurance Program Implementation During Construction and Pre-Construction Activities; Update NRC guidance documents to incorporate lessons learned as needed; Communicate lessons learned publically via issuing generic communications.

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NUREG-1055, Improving Quality and the Assurance of Quality in the Design and Construction of Nuclear Power Plants covers among other things, historical concrete issues. See ML063000293; NUREG/CR-6927, Primer on Durability of Nuclear Power Plant Reinforced Concrete Structures - A Review of Pertinent Factors. See ML070850183; IN 2008-17, Construction Experience with Concrete Placement. See ML081850581; IN 2011-20; Concrete Degradation By Alkali-silica Reaction. See ML112241029; 13

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