Total stress approach for stability of seabed under wave loads

The evaluation of seabed stability is an important part for the design of various marine facilities. Based on the classic theory of elasticity, the total stress solutions for layered elastic seabed under linear wave loads are derived by means of the semi-inverse method, and then according to the Mohr-Coulomb failure criterion, seabed shear failure is analyzed on the basis of the solutions. The results show that the shear modulus of soils which increases linearly along with the seabed depth has a significant effect on the distribution of stress angle, especially when the seabed thickness is less than a half times the wavelength. The easiest place to initiate shear failure is located at a certain depth below the seabed surface. However, for the homogeneous seabed, it is located at the surface of seabed . The stability of seabed is also affected by weak interlayer. The more shallow the depth of the weak interlayer, the more easily the shear failure of soil layer occurs on the weak interlayer.