lification in parameters A and V. Table 3 lists the ratios by which A
and V should be increased in the R-E method, and in the Wong method,
in order to reflect the effects of ground motion amplification on wall
displacement. For example, A and V should be increased by a factor of
1.38 in the R-E method (Eq. 3), and 1.34 in the Wong Method (Eq. 4)
for N = 0.112 and A = 0.2, so that the expected displacement, D, increases
by a factor of 5. This factor reflects the effects of amplification
of the Taft earthquake, scaled to a peak acceleration of 0.2 g, on the
permanent displacement of a wall that has a backfill with ///I = 0.53.