Abstract:Previous laboratory testing studies showed that marine soft soil in Hangzhou is a structural soil,which has obvious structural effect. But in this research,shear shrink phenomenon of the marine soft soil is only observed in shear tests,and the stress-strain curve of the marine soft soil is of hardening of special pattern. These two characteristics differ from typical strain softening of structural soil,so it can be concluded that marine soft soil in Hangzhou is a special structural soil. The pre-consolidation pressure and structural yield stress of the soil are obtained,the rules of structural strength varying with cover depth and damage rules under varying uniaxial compressive pressure are determined. Then,the calculation of structural strength of structural soil is optimized,and the concept structural strength is clarified.