ACTIVE EARTH PRESSURE ON RETAINING WALLS OF NARROW BACKFILL WIDTH

Abstract

The earth pressure acting on the retaining wall is usually based on Rankine's limit equilibrium theory and Coulomb's solid sliding mass equilibrium theory. Both methods assume that the backfills can extend to a sufficient distance for the failure plane to fully develop. Therefore, these approaches cannot account for the influence of the backfill width behind the wall. In practice there are many cases of narrow backfill behind the wall. For example, reinforced walls are built in front of stabilized walls or rock, or structures with deep excavations are built near existing underground structures in urban areas. In these cases, the narrow backfill has a significant effect on the full development of a failure wedge according to Rankine's or Coulomb's theory. In this paper, the active earth pressure acting on the wall with a narrow backfill is determined based on Coulomb's theory. The results of the paper show that the earth pressure acting on the wall is significantly reduced when the soil width behind the wall is narrow. This result can be applied in real design cases.