Terzaghi's one-dimensional consolidation theory is modified by considering seepage force
the consolidation equations under both upward and downward seepage are derived and the distribution of the seepage stress during consolidation is also analyzed.It is concluded that the seepage force affects on the consolidation degree obviously
especially when Tv is about 0.1
the values of the consolidation degree considering the seepage force or not will have the difference of 30 %. The author believes that the seepage force cannot be neglected.