Consolidation of Normally Consolidated Clay

Based on the idealized physical properties of saturated, normally consolidated clay, a simple nonlinear theory of one-dimensional consolidation is developed and solved by means of finite difference approximations. To assess the validity of the theory, tests were conducted on three remoulded saturated clays in 10-in. diameter oedometers in which settlements, pore pressures, and total stresses were measured. It was found that for the materials tested, the nonlinear theory is in closer agreement with the observations than the linear Terzaghi theory. For tests in which the variation in permeability is marked, the Terzaghi theory gives poor agreement between settlement and pore pressure observations. However, for normal pressure increments in saturated clays that do not exhibit a marked decrease in permeability or other unusual characteristics, the Terzaghi theory appears to be adequate for all practical purposes, particularly at the field scale where the effects of structural viscosity are less dominant.