CONSOLIDATION WITH CONSTANT RATE OF DEFORMATION

The moving boundary theory of consolidation is used to study a thin specimen undergoing a constant rate of deformation: an idealized condition in the so-called constant rate of strain consolidation test. This is in contrast to previous small strain theories in that a realistic boundary movement is allowed in the mathematical model, which is thus suitable for both small and large strain conditions. The equation is solved numerically and it is found that the solution is dependent on the deformation rate used, this being characterized by a parameter β. An approximate solution based on the assumption of a parabolic strain distribution is developed and compared with the numerical solution. A new method of interpreting test results, valid for small values of β, is proposed. This limitation of β sets an upper limit of deformation rate that can be used in a test. La theorie des conditions aux limites variable relatives a la consolidation est utilisee pour etudier un echantillon mince soumis a une deformation de t...