Idaho Falls, ID
Idaho National Laboratory, Advanced Test Reactor, Primary Heat Exchangers Upgrade
Scope/Solutions
The Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) supports research and testing of materials for use in large-scale and prototype reactors. Previous analysis by BEA raised potential concerns with the primary heat exchanger supports under a design earthquake. SGH evaluated the seismic performance of the primary heat exchanger supports and designed necessary upgrades.
The approximately 38 ft tall by 6 ft dia. heat exchangers located inside the reactor building are supported at their base by reinforced concrete piers, steel columns, and concrete walls; and are laterally supported near their top by tie rod bracing. For this project, SGH performed a structural evaluation and designed the upgrade for the primary heat exchanger supports for Performance Category 4 (PC-4)/Seismic Design Category 5C (SDC-5C) compliance. Our upgrade strategy focused on maintaining the stiffness of the existing load paths to preserve the validity of BEA’s previous dynamic analysis. Upgrades include new:
- Upper tie rod bracing and ductile anchorage
- Steel jacketing of supporting concrete piers for lateral and vertical confinement
- Ductile lateral load path and base anchorage at the concrete piers
- Ductile lateral load path and anchorage at the walls
We prepared calculations, design drawings and specifications, and three-dimensional fabrication and assembly drawings. SGH delivered a formal presentation to our client and our design work was independently reviewed and accepted. We also provided construction administration services that included review of the temporary scaffolding system.