Consolidation at Constant Rate of Strain

A new general purpose consolidometer for studying the one-dimensional consolidation behavior of soils is described. The test specimen can be loaded incrementally, as in the conventional test, at a constant rate of stress, or at a constant rate of strain. The apparatus can also be used to measure residual pore pressures and swell pressures during back pressure saturation at constant volume. Pore pressures are measured at the impervious base, and free drainage occurs from the top surface. A general solution to the consolidation equation is derived for conditions of constant rate of strain assuming constant c_v. While particular solutions are given for both a linear soil having constant m_v and a nonlinear soil with constant C_c, it is shown that for most purposes the linear solution is sufficiently accurate for interpreting constant rate of strain (CRSC) test results. The CRSC test is shown to be a simpler and much faster method for measuring the consolidation characteristics of soils than is the conventional test.