Research Spotlight: Rigging and Bracing Stability: Considerations For Moving, Lifting and Placing a Non-Building Structural Module
2017 Annual Stability Conference Presentation
Session SS1B – Technical Presentations: Special Topics in Structural Stability
Tuesday, March 21, 2017
Rigging and Bracing Stability: Considerations For Moving, Lifting and Placing a Non-Building Structural Module
One of the large structural steel-plate wall modules in the AP1000 nuclear power plant makes up a significant part of the In-containment Refueling Water Storage Tank (IRWST). This outer circular portion of the tank consists of a stainless steel plate stiffened with structural sections in the vertical direction and angles in the horizontal direction. The stability issues associated with this open-walled structural module had to be addressed as it is being placed inside the Containment Building. More importantly, when this same structural module was rigged with a four-point lifting plan in China, its overall stability came into question. A new eight-point rigging, temporary structural braces, and lifting plan was created for the U.S. AP1000 plants that considered not only the stability of the structural module, but of the rigging members that would be employed in the lift and ultimately the placement of the module. Finite element analysis simulations of the lift were performed to evaluate the stresses and stability of the structural module and rigging including the new lifting locations and lug plate designs that were determined.
Michael Mudlock, Simpson Gumpertz & Heger, Inc., Houston, TX; Perry S. Green, Bechtel Power Corporation, Waynesboro, GA; Andrew Sarawit, Simpson Gumpertz & Heger, Inc., Waltham, MA; Francis J. Byrne, Westinghouse (WECTEC), Waynesboro, GA