Loess ground has obvious collapsible characteristic. Three methods, namely DDCpile, compaction pile and dynamic

consolidation, were adopted in this test. The Rayleigh dispersion curves of three methods were tested before and after the

treatment, the Rayleigh velocities were compared, the shear wave velocity was inversed, and then the wave velocity variation of the

loess ground was obtained. The results indicate that all the elastic wave velocities are increased, the increasing amplitude of the

three methods are in order of DDCpile, compaction pile and dynamic consolidation. The transient Rayleigh wave method was applied

to nondestructive test so as to get to know the result of large area ground treatment.