Which option best describes a defect caused by inadequate bedding?

• A. Thermal expansion
• B. Pressure surges
• C. Corrosion
• D. Horizontal breaks

Answer: (D)

Imperfect bedding means the object isn’t sitting on a solid, uniform support, so it can’t carry loads evenly. That uneven support causes the material to bend and crack along its length, resulting in cracks that run horizontally across the section — horizontal breaks. This specific pattern of damage comes from the way the load is transmitted through the bedding to the underlying surface. The other issues arise from different mechanisms: thermal expansion is about changing size with temperature, pressure surges come from sudden hydraulic forces, and corrosion is a chemical degradation process. So the defect most directly tied to inadequate bedding is the appearance of horizontal breaks.