Evaluation of Post-Surcharge Secondary Settlement Characteristics by Constant Rate of Strain Test

摘要

In general, settlement during sustained loading should be minimal because the sustained loading pressure is less than the preloading pressure. However, there have been several examples of a large degree of settlement occurring during sustained loading. In this study, the loading history was simulated by means of a constant rate of strain (CRS) test in order to determine the post-surcharge secondary consolidation behavior during the sustained loading process. The results of this test were compared with those of an incremental loading test and in situ test. The results of this study were as follows: (1) the loading history can be simulated via the CRS test, (2) the post-surcharge secondary compression index depends on the over-consolidation ratio, (3) the post-surcharge secondary compression index changes with time, and (4) when sustained loading is induced, the post-surcharge secondary compression index is smaller than when there is no previous loading history.