As vertical loads are applied, a flexible culvert attempts to deflect.

• A. False
• B. Not sure
• C. N/A
• D. True

Answer: (D)

A flexible culvert responds to vertical loads by bending and shifting shape, so deflection is the natural outcome. When weight from traffic, backfill, and soil loads acts on a flexible culvert, it does not stay perfectly rigid; instead, it deforms to redistribute those forces through the culvert and surrounding soil. That tendency to bend and move under load is why deflection is expected and measured as part of the structure’s serviceability. So stating that a flexible culvert deflects when vertical loads are applied aligns with how these materials behave in practice. The other options don’t fit because a nonrigid, bendable element will not remain undeformed under load, and uncertainty or irrelevance aren’t appropriate responses to this physical behavior.