Applicability and development of in-situ freezing sampling method to sandy and gravelly soils

In order to construct large important structures on granular ground, technology to correctly evaluate the mechanical properties of bearing stratum in ordinary condition and during earthquakes is indispensable. In-situ freezing sampling method becomes a very useful method for laboratory tests to evaluate mechanical properties of granular ground, by the undisturbed samples taken from the ground which is frozen in advance. In this report we describe a study of applicability of in-situ freezing sampling method to granular ground. Therefore, we have developed sampling techniques for taking hi-quality undisturbed samples from granular ground, and examined its applicability to actual ground by the use of this technique, along with the investigation on the effect of freezing and thawing on mechanical properties of sand and gravels by laboratory basis test, to report the results here. (author)