For a retaining wall subjected to horizontal earth pressure, the factor of safety against sliding (where If is weight) is given by_____________?
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Answer: C. 1.5
Explanation
Standard retaining wall design guidelines specify a minimum factor of safety against sliding equal to one point five. The factor of safety compares resisting frictional forces against the destabilizing horizontal earth pressure acting on the wall stem. Maintaining a 1.5 ratio ensures that lateral soil pressures will not push the masonry or concrete structure forward over time. Retaining walls are engineering structures designed to hold back soil masses and create level building platforms on sloped terrain. Stability checks for retaining walls include evaluating safety factors against overturning, sliding, and bearing pressure failures. Friction developed at the base slab interface provides the primary resistance against horizontal sliding forces caused by backfill.
A factor of safety of 1.0 indicates a state of neutral equilibrium where resisting forces exactly equal sliding forces without safety margin. One point twenty five represents an inadequate safety margin for permanent earth retaining structures subject to variable soil loads. A factor of 2.0 is often unnecessarily conservative for standard sliding checks, making 1.5 the widely accepted industry standard.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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