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Earth Pressure Test Pit

The Instrumented Retaining Wall Facility, which is 7 feet high and 10 feet long, has been developed to study both the factors that control the magnitudes of earth pressures induced by compaction and the influences that wall movements have on earth pressures.  Previous investigations have shown that measuring the earth pressures that results from compaction is difficult because:

  • Earth pressure cells sometimes give erroneous readings depending on their stiffness and how they are installed.
  • Compaction-induced earth pressures vary rapidly with depth, resulting in misinterpretation if fill elevations are not measured with sufficient accuracy.
  • There appear to be large inherent variability in earth pressures, resulting in possible erroneous evaluations if too few measurements are made.
  • Small wall movements can change earth pressures very significantly. Wall must be stiff and mounted on unyielding supports to measure earth pressures that are not influenced by wall movements.

The experimental facility at Virginia Tech has been designed to overcome these problems and to achieve accurate measurements of compaction-induced earth pressures at a scale approaching field scale.

The facility is also has instrumented wall panels that  can be moved towards and away from the backfill to measure the effects of wall movements on earth pressures, and the wall panels are instrumented so that shear loads as well as normal loads can be measured. The facility can be used to investigate earth pressures due to loads on the surface of backfills, and to study how the results of in situ tests are affected by soil density and lateral earth pressures.

For more information about the wall please click here .