ABSTRACT
The history, background and the main achievements for a period between 1994 and 2001 of TC-29 entitled “Stress-Strain Testing of Geomaterials in the Laboratory” of ISSMGE are reviewed by the authors. During the period, the devices, procedures and data acquisition systems for laboratory stress-strain testing of geomaterials have all shown significant developments, with which the in-situ stress-strain behaviour of geomaterials in use for predicting ground deformation and structural displacement can now be evaluated much more reliably and realistically than before. It is pointed out that the stress-strain behaviour over a ‘practical’ range of strain, which is usually less than about 0.5 % with stiff geomaterials, is often highly non-linear against strain, and very sensitive to pressure changes. It is emphasised that the stress-strain property of geomaterials for a strain range from less than 0.001 % to that at the peak can be evaluated by performing relevant laboratory stress-strain tests using a single specimen.
