Q59. In an underground warehouse, the external walls:
  • are designed as curtain walls
  • are designed as retaining walls with or without surcharge.
  • are designed only by vertical loads imposed by upper floors.
  • do not share any dynamic loads caused by the movement of trucks and fork lift vehicles.

Correct Answer: B. are designed as retaining walls with or without surcharge.

Solution:

The external walls of any underground structure, including a warehouse, must be designed to resist the lateral (horizontal) pressure from the surrounding soil. This is the primary function of a retaining wall. Additionally, any loads on the ground surface near the wall (like traffic, equipment, or stored materials) create a 'surcharge' that adds to this lateral pressure and must be included in the design.