Which statement about lifting tilt-up panels is accurate?

• A. Panels may be lifted prior to the concrete reaching design strength
• B. Panels may be lifted only after design strength is achieved
• C. Panels should never be lifted
• D. Panels are lifted only after curing for 7 days

Answer: (A)

Early-age strength development in concrete governs when a tilt-up panel can be safely lifted. The panel must have enough initial strength to resist the lifting and handling stresses, plus the forces from temporary bracing and the crane. This strength is typically less than the full design strength, and the lift is allowed once cylinder tests and the engineer’s approval confirm the minimum early strength is reached. Waiting for full design strength would unnecessarily delay construction, and strength clearly isn’t required to be fixed at seven days—the timing depends on mix, curing conditions, and actual test results. The use of temporary supports and proper lifting hardware ensures the panel is held securely during the lift.