Constant Rate of Strain (CRS) tests were carried out on three types of undisturbed and two types of remolded clays. CRS test is one of the continuous loading test and has advantages over conventional incremental loading test (STD test):(1) CRS test can be obtain continuous stress-strain curve that is useful for sensitive clay:(2) it is completed in shorter duration:(3) test method can be easily automated. However it is well known that the consolidation yield stress,pc estimated by CRS test is greater than that obtained by STD test due to strain rate effect.
　In this report, in order to investigate strain rate effect, a series of CRS test was carried out on two types of remolded clays. A simple method to modify pc using stress relatxation test is proposed and applied to CRS test results on three types of undisturbed clays.
　Main conclusions are as follows:
(1) The consolidation yield stress, pc from CRS test increses linearly with the strain rate.
(2) Using the method proposed in this report, the pc from CRS test agrees favorably with pc from STD test.