Based on a series of laboratory tests on soft soil in Nansha

Guangzhou

involving direct shear test

unconfined compression test

consolidation test

the structural characteristics of the regional soft soil are studied. By using undisturbed and remoulded soil samples

shear deformation

shear strength and consolidation properties of the structured clay which indicate the significant structure of the soil and the effect on engineering property are analysed. The test results show that the shear strength of disturbed structure clays obviously declines and the compressibility increases; the consolidation process of undisturbed samples can be considered as three phases

which relating to structure yield stress. For remoulded structured samples

the dividing line of compression and secondary compression by compression-log time curve

obtained from oedometer tests

is more obvious than undisturbed specimen

in case of loaded be same. It can be concluded that structure yield stress

which can be defined by compression coefficient a-consolidation pressure p curve

is one of the important factors for controlling deformation of structured clay. The influence of structure on mechanical properties decreases as the consolidation pressure increases. When consolidation pressure is higher than full structural yield stress

the effect of structure can be neglected.