This project is supported in the Phase 2 (second year) program of the Seismic Repair/Rehabilitation Research Initiative (NSF 90-23). Precast concrete tilt-up structures are widely used throughout the U.S. for one and two-story warehouses, office buildings, and shopping centers. Tilt-up structures are economical to build; however, they are susceptible to severe structural damage during earthquakes. The objective of this project is to develop guidelines for evaluating the seismic hazards in existing tilt-up construction and develop methods for mitigating those hazards. The work focuses on four areas: (1) connection of the roof diaphragm to the tilt-up wall panels, (2) connection between adjacent wall panels, (3) connection of the wall panels to the floor slab and foundation, and (4) strength and stability of wall panels with large openings. Analytical models will be developed to calculate the dynamic response of building systems used throughout the U.S. and laboratory tests of representative details and structural systems will be performed.
