Engineering Considerations for Lift-Slab Construction

Sponsored by the Task Committee on Lift-Slab Construction of the Technical Council on Forensic Engineering of ASCE.

In 1987, the collapse of Ambiance Plaza in Bridgeport, Connecticut, demonstrated the need to re-evaluate the engineering of lift-slab construction and determine what is needed to make it safe. This report addresses engineering requirements for lift-slab construction and presents recommendations to engineers, architects, and lift-slab contractors for its safe use.

Topics include:

• Concepts and details of various lift-slab systems;
• Theories on the cause of the Ambiance Plaza collapse;
• Discussions on other failures and problems;
• Considerations and recommendations for lifting collars and lifting equipment;
• Considerations and recommendations for stability;
• Recommendations for construction loads;
• Discussions and recommendations for preventing progressive collapse; and
• Considerations for planning and execution of lift-slab projects.