The model tests of sheet pile wall with relieving platform by use of geometric similarity coefficient of 7 and its different conditions are introduced briefly. The earth pressure distributions on upper wall with changing of the width and depth of relieving platform under the conditions of embankment and an external load are analyzed emphatically. The results show that: ①The depth of relieving platform exceeds a certain depth

which can't improve effectively the distribution of active earth pressure on the upper wall; in turn that exists best depth location. ②The change of width of relieving platform has a great influence on earth pressure near the surface of relieving platform

but has no effect on the overall distribution trend of earth pressure on upper wall. ③In the embankment load

when the ratio of the relieving platform width to the height of upper part wall is less than 0.4，the distribution of earth pressure on the upper wall is close to the Rankine's earth pressure; when the ratio is more than 1.3

the distribution of earth pressure on the upper wall is close to the at rest earth pressure. ④In engineering design

it is suggest that the upper part wall earth pressure can be calculated by the formula