If the maximum unsupported wall height is 8 feet and the maximum unbalanced backfill height is 7 feet, what is the minimum vertical rebar size and spacing?

To determine the minimum vertical rebar size and spacing required for a wall with a maximum unsupported height of 8 feet and a maximum unbalanced backfill height of 7 feet, it is essential to consider structural integrity, load distribution, and the wall types in use.

The correct answer indicates a requirement of 6 bars at 48 inches apart. This specification is designed to provide adequate reinforcement to handle the lateral pressures imposed by the unbalanced backfill and ensure the wall remains stable under these conditions. Proper spacing of rebar is critical in preventing structural failure, and typically, walls that incur significant lateral loads necessitate closer spacing of rebar to resist those forces effectively.

In this instance, the decision to opt for 6 bars at 48 inches aligns with industry standards for walls facing similar conditions—addressing both the height and load requirements adequately. Furthermore, adhering to these recommendations helps ensure compliance with building codes that govern safety and structural performance for walls subject to unbalanced backfill.

In summary, the emphasis on the provided rebar size and spacing is based on the need for structural stability and the requisite load-bearing capabilities of walls in construction scenarios that involve significant pressures from materials such as backfill.