“…Moreover, previous studies (e.g., Gonzalez-Radriguez and Madsen, 2007;Hemer et al, 2004;Jia et al, 2007;Myrhaug and Ong, 2009;van Gent et al, 2008;You, 2000You, , 2005 investigated wave-induced sediment erosion in laboratory and in-situ experiments, field observations, and theoretical models to find the effects of waves on sediment erosion and explore the mechanisms of the dynamic response of seabed sediment to waves. Although a number of studies (e.g., Chang et al, 2006;Liu and Jeng, 2007;Liu et al, 2006;Zen et al, 1998) showed that the mechanism of waveinduced seabed instability can be classified into two major types, shear failure and liquefaction, studies (e.g., Hemer et al, 2004;Myrhaug and Ong, 2009;Tanaka and van To, 1995) about seabed sediment erosion analysis in hydrodynamic conditions mainly focused on wave-induced stresses on the seabed and evaluation of resistance strengths of given seabed sediment. Generally, forces exerted on the seabed by waves can be classified into two types, level circulating shear stress and vertical pressure, which are considered the leading factors inducing shear failure and liquefaction of seabed sediment.…”