Impact of structural aging on seismic risk assessment of reinforced concrete structures in nuclear power plants

Technical Report · Fri Mar 01 04:00:00 EST 1996

DOI:https://doi.org/10.2172/219359· OSTI ID:219359

Ellingwood, B; Song, J ^[1]

---

1. Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Civil Engineering

The Structural Aging Program is addressing the potential for degradation of concrete structural components and systems in nuclear power plants over time due to aging and aggressive environmental stressors. Structures are passive under normal operating conditions but play a key role in mitigating design-basis events, particularly those arising from external challenges such as earthquakes, extreme winds, fires and floods. Structures are plant-specific and unique, often are difficult to inspect, and are virtually impossible to replace. The importance of structural failures in accident mitigation is amplified because such failures may lead to common-cause failures of other components. Structural condition assessment and service life prediction must focus on a few critical components and systems within the plant. Components and systems that are dominant contributors to risk and that require particular attention can be identified through the mathematical formalism of a probabilistic risk assessment, or PRA. To illustrate, the role of structural degradation due to aging on plant risk is examined through the framework of a Level 1 seismic PRA of a nuclear power plant. Plausible mechanisms of structural degradation are found to increase the core damage probability by approximately a factor of two.

• Research Organization: Nuclear Regulatory Commission, Washington, DC (United States). Div. of Engineering Technology; Oak Ridge National Lab., TN (United States); Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Civil Engineering
• Sponsoring Organization: Nuclear Regulatory Commission, Washington, DC (United States)
• DOE Contract Number: AC05-96OR22464
• OSTI ID: 219359
• Report Number(s): NUREG/CR--6425; ORNL/TM--13149; ON: TI96009921
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
22 GENERAL STUDIES OF NUCLEAR REACTORS
36 MATERIALS SCIENCE
AGING
CONCRETES
CONTAINMENT BUILDINGS
CORROSION
DATA
DESIGN BASIS ACCIDENTS
EARTHQUAKES
MECHANICAL STRUCTURES
NUCLEAR POWER PLANTS
REINFORCED CONCRETE
RELIABILITY
RISK ASSESSMENT
SEISMIC EFFECTS
ZION-1 REACTOR