FULL-SCALE RETAINING WALL TESTS WITH EVALUATION OF WORKING ANGLE OF INTERNAL FRICTION

Abstract

  Through the 6 meter high retaining wall test series, the behavior of earth pressures acting on the rigid retaining wall is discussed. The fill materials used were sand and cohesive soil with natural water content. Earth pressures were measured during the filling and the wall yielding stages.
  Test results were evaluated by the working angle of internal friction (φ_wrk) on the sliding plane in Coulomb's wedge, which is derived by the measured resultant force and its inclination on the test wall.
  The compacted backfill of sand shows various phases of earth pressures, i.e. pressures during filling, upon completion of filling, and in active and residual states, while cohesive backfill is likely to behave like friction material and show recovery in terms of earth pressure in an active state. Moreover the derived angle of the sliding plane from φ_wrk effectively explains the position of the actual sliding plane, which determines the influence area of the earth pressure.
  Based on a view of the design earth pressure, evaluation of the working angle of internal friction (φ_wrk) upon fill completion will be practical.