Abstract:

The statistical relationship between shear wave velocity and depth for conventional soil types (“Relationship Between Shear Wave Velocity and Depth of Conventional Soils”，by Liu Hongshuai， et al，power function and one-quadratic model equations in Tables 2 to 5) is a national empirical equation. It has become an important reference for testing and comparing empirical equations in many regions, but lacks a more systematic evaluation of reliability. Therefore, the statistical empirical equation of shear wave velocity and depth in typical domestic regions (Beijing, western Shandong, Chengdu，Tianjin, Changzhou and Wuhan) are selected to test the reliability of the empirical equation of the national shear wave velocity and depth of conventional soils. The results show that: The power function model predicts that the shear wave velocity increases with depth, which is consistent with qualitative understanding, while the quadratic model may exhibit unreasonable bending anomalies and should not be used. The prediction accuracy of the national shear wave velocity empirical equation varies significantly in different regions. In most regions, the absolute relative errors of the prediction for the vast majority of soil types are generally less than ±20%. The absolute relative errors are larger only within 20 m of the near-surface, with a maximum of about 40%. In a few areas, the absolute relative errors of the prediction are greater than 20%. It is recommended to prioritize the selection of shear wave velocity empirical formulas suitable for local conditions; When there is a lack of local equations and it is necessary to choose the national power function type empirical equations for shear wave velocity, it should be tested and confirmed by the local measured data before use; The shear wave velocity within the 20 m range is best determined by actual measurement, which helps to reduce the significant errors brought by the national shear wave velocity empirical formula. 

Key words: conventional soils, shear wave velocity, depth, reliability, empirical equation