Numerical simulation of Rayleigh wave zigzag dispersion curves of four typical strata
四种典型地层的瑞雷波“之”字型频散曲线数值模拟研究

MASW technology is widely used in stratum exploration, but its application is limited because of insufficient theoretical guidance, especially numerical simulation research .This article used the finite element software LS-DYNA to study the characteristics of Rayleigh wave zigzag dispersion curves (extracted by MASW method) of four typical strata (stratum of Rayleigh wave velocity increasing with wavelength, stratum with a soft under-layer, with a weak interlayer, and with a hard interlayer) by numerical simulation method. We found that the Rayleigh wave dispersion curve of the first stratum does not show zigzag, however, the Rayleigh wave dispersion curves of the other strata display different zigzag types. Among the four strata, the zigzag position and size of the stratum including a weak interlayer matches well with the position and layer thickness of the weak interlayer. The results of the article offer important reference for using dispersion curve shape to determine stratum types and position of weak interlayer in actual engineering.