Shear wave velocity of seabed sediment from laboratory measurements and its relationship with physical properties of sediment

Both piezoelectric ceramic bender element and resonant columntest technologies were used to measure effectively the shear wave velocity of seabed sediments from the East China Sea and the South China Sea in laboratory.Shear wave velocity data measured by these two methods appeared to be good consistency and no obvious frequency dispersion was found from a few hertzs to tens of kilohertzs.The shear wave velocity changed greatly in different physiographic areas and different sediment types.According to measurement data, the shear wave velocity of inshore silts is about 100 m/s and finer sediments show less than 100 m/s velocity.Coarse sediments on continental shelves are characterized by maximum shear wave velocity values, all more than 100 m/s, and fine deep-sea sediments have minimum shear wave velocity values, generally less than 50 m/s.The shear wave velocity shares a good correlation with physical properties of sediment,such as water content, density, porosity,plastic limit and liquidlimit of sediment,which reflects a strong relationship between them.The shear wave velocity also shows a positive correlation with the compressional wave velocity, but the ratio of shear wave velocity to compressional wave velocity changes obviously with the compressional wave velocity valuerange.