Interactions between sands to liquefaction and piles were studied using shake table model tests. The relationships between pile bending moments and cyclic cumulative pore water pressure ratio were obtained for different relative densities sands to liquefaction. Degradation p-y curves of soil-pile interaction were determined during the sand to liquefaction using pseudo-static method. Bending moments along the pile are further calculated using the nonlinear Winkler foundation beam and degradation p-y curves. Calculating and test bending moments were compared. Results show that the lateral resistance of the pile does not reduce if the cyclic cumulating pore water pressure ratio ru≤0.2

it degrades 90 % if the relative density of sands Dr≤40 % and the cyclic cumulating pore water pressure ratio ru≥0.8 and it degrades 75 % if the relative density of sands Dr≥50 % and the cyclic cumulating pore water pressure ratio≥0.8.