Abstract: The primary sediment in the Yellow River delta is silt. It is not clear how the permeable and impermeable interlayers impact on the accumulation of the pore water pressure?dissipation and liquefaction of sediments under the cyclic loading.This paper presents results of in-situ vibration test and lab tests for four kinds of interlayers.The results show that physical and mechanical properties of the silt,such as the pore water pressure,grain size composition,density,water contents etc.vary with the type of interlayer?A permeable layer improves its resistance against liquefaction,while an impermeable interlayer is opposite.