A study is made of various types of viscoelastic effective stress-strain relations, and their influence on the time-settlement relations in secondary consolidation. This study examines both deviatoric and volumetric components of the effective stress-strain relations. It is shown that the effective stress-strain relationship for a clay layer, is derivable from several combinations of volumetric and deviatoric behavior.
A five-parameter relationship is discussed and generalized to a continuous one by functionals. The influence of various rheological parameters are discussed.
Experimental evidence is introduced for several normally consolidated and over consolidated clay samples. The rate of secondary consolidation is approximately the same for both isotropically consolidated triaxial tests and for oedometer tests. The rate of secondary consolidation is lower for the over-consolidated samples.
An explanation of behavior is presented in terms of the physio-chemistry of the clay-water system. This study considers the particulate nature of clays and two types of effective stress transmission; these being contact stresses and double layer stresses.