Earthquake response of head-mounted equipment in advanced nuclear reactors

Journal Article · 07 August 2023 · Earthquake Spectra

DOI: https://doi.org/10.1177/87552930231189459 · OSTI ID:1994019

Mir, Faizan Ul Haq  ^[1]; Tilow, Kaniel ^[2]; Nguyen, Nam ^[3]; Song, Brian ^[3]; Clavelli, Matthew ^[3]; Kosbab, Benjamin D. ^[2]; Whittaker, Andrew S. ^[1]

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1. University at Buffalo, Buffalo, NY, USA
2. Simpson Gumpertz & Heger, Atlanta, GA, USA
3. Kairos Power, Alameda, CA, USA

The seismic response of safety-related equipment mounted on the head of an advanced reactor, including pumps, control rod drive mechanisms, and reactor monitoring devices, will affect the design and layout of many advanced reactors. High earthquake-induced accelerations in such equipment may challenge their seismic qualification and trigger the need for additional support framing on the reactor head. Base isolation is a design solution that can drastically reduce seismic demands on equipment. This article describes a set of earthquake-simulator experiments conducted on a scale-model of a base-isolated reactor vessel including four representations of head-mounted equipment, with frequencies spanning from 4.5 to 27 Hz. Dynamic responses of the head-mounted equipment, including displacements, accelerations, and strains, were measured in the experiments for three support conditions: conventional, and seismically isolated using single concave Friction Pendulum (SFP) bearings and triple Friction Pendulum (TFP) bearings. Seismic isolation was effective at reducing equipment responses (accelerations, displacements, and strains) with respect to those in the conventionally supported vessel across a range of seismic inputs. Companion numerical studies highlight the accuracy to be expected in the calculation of different response quantities for lightly damped equipment. The importance of characterizing damping in head-mounted, safety-related equipment through physical experiments to support design and risk assessment is made clear through the numerical simulations.

• Sponsoring Organization: USDOE
• Grant/Contract Number: AR0000978
• OSTI ID: 1994019
• Journal Information: Earthquake Spectra, Journal Name: Earthquake Spectra Journal Issue: 4 Vol. 39; ISSN 8755-2930
• Publisher: SAGE PublicationsCopyright Statement
• Country of Publication: United States
• Language: English