EXPERIMENTAL AND MATHEMATICAL INVESTIGATIONS ON UNCONFINED COMPRESSIVE BEHAVIOUR OF COSTAL SOFT SOIL UNDER COMPLICATED FREEZING PROCESSES

In order to properly understand the effect of freezing-thawing circle (FTC) to mechanical behavior of costal soft soil (CSS), unconfined compressive test is conducted. Six kind FTC times are designed from zero to five. The tested data show that: (1) unconfined compressive strength of CCS decreases nonlinearly with more FTC, and the strength after five FTC times becomes about 22% of its original strength without any freezing-thawing experience; (2) stress-strain curves of all unconfined compressive samples can be well fitted by three-parameter hyperbolic model; (3) and relationship between two parameters and FTC times can be fitted by exponent function, while another parameter can be considered as 0.95. Consequently, one composite hyperbolic-exponent empirical formula is established in order to describe freezing-thawing-dependent stress-strain behavior of CSS. Finally, good agreements have been found between tested dada and simulated results.