Which statement about tilt-up foundations is true?

• A. Rafts or mat slabs cannot be used.
• B. Rafts or mat slabs are acceptable.
• C. All foundation types are acceptable.
• D. Foundations do not affect panel weight.

Answer: (A)

Foundations for tilt-up must provide a stable, level base that can securely transfer the weight of the wall panels and accommodate the anchorage connections used during erection. A raft (mat) foundation is a valid option in tilt-up projects when the soil conditions support a large, continuous bearing surface and the design accounts for the panel connections, joints, and potential movement. Using a raft distributes loads over a wide area, helps control differential settlement across the building footprint, and provides a consistent plane for embedding anchor bolts and other connection hardware that tie the panels to the foundation. This makes it a practical choice in many tilt-up applications, rather than ruling it out completely.

The other statements don’t hold up under typical practice. Not every foundation type is automatically suitable for tilt-up, since the chosen system must effectively carry panel loads and allow proper anchorage and tilting operations. And the foundation does influence how panel weight is transmitted and how the structure behaves during erection, so saying foundations don’t affect panel weight isn’t accurate.