Interpretation of coefficient of consolidation from CRS test results

摘要

Constant rate of strain (CRS) consolidation tests were conducted for undisturbed Ariake clay samples from three boreholes in Saga Plain of Kyushu Island, Japan. The coefficients of consolidation (c_v) were interpreted from the CRS test results by small- and large-strain theory. Large-strain theory was found to interpret smaller c_v values and less strain rate effect on c_v than that by small-strain theory. Comparing the theoretical strain distributions within a soil specimen to those obtained by numerical simulation shows that the small-strain theory can be used only for the dimensionless parameter c_v/ εH_0~2 ≥50 (where ε is strain rate and H_0 is the specimen height), and the large-strain theory can be used for a larger range of strain rates. Applying the criterion to undisturbed Ariake clay with a c_v value of about 1 × 10~(-7) m~2/s, it is suggested that the large-strain theory should be adopted for calculating the c_v value when ε ＞ 0.03%/min.