Undrained anisotropic behaviour of K₀-consolidated marine clay under cyclic stresses

Abstract

To investigate the effect of major principal stress direction angles on the cyclic response of soft marine clays, a series of directional shear tests with different major principal stress direction angles on undisturbed Wenzhou marine clay were conducted in the undrained condition by using a hollow cylinder testing apparatus. The dynamic responses of the marine clays were analysed, along with the shear stress-strain relationship, octahedral strain and excess pore water pressure. Results indicate that the specimens exhibit remarkable anisotropic deformation under various major principal stress direction angles, and a larger angle causes a smaller octahedral strain of specimen under the same cyclic stress level. With the increase in the major principal stress direction angle, the excess pore water pressure decreases. At β > 45°, the increment shear stress starts dominating, which causes the sign of generated pore water pressure to change from negative to positive.

Keywords:

• Soft marine clay
• anisotropy
• hollow cylinder apparatus
• principal stress direction angle
• octahedral strain

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was financially supported by the National Key R&D Program of China under grant [2016YFC0800200] and National Nature Science Foundation Projects of China under grant [51778500].