Desaturation is a mitigation method for sand liquefaction. Reducing saturation has been proposed to improve liquefaction resistance of saturated sandy foundation. Comparison of the centrifuge test numerical simulation was carried out

based on the modified single-phase fluid numerical method with simultaneous updating fluid modulus and the simplified method with fixed fluid modulus. The results show that the modified method is more reasonable because it considers the change of fluid modulus due to pore pressure change. The simplified method will underestimate the accumulation of pore pressure in the desaturated sand. Numerical simulation of liquefaction deformation on gently tilting desaturated sandy ground with different saturations and angles is carried out based on the modified single-phase fluid numerical method. The results show that the increasing velocity and peak value of excess pore pressure increase with the increase of saturation. The peak value of the excess pore pressure decreases by 20%-65%

and the peak value of acceleration response decreases significantly at the same depth with the saturation decreased from 100% to 96.4%. Along the foundation depth from 0.75 m to 9.00 m

lateral deformation decreases by about 20%-50%. It can conclude that the saturation reduction plays a positive role in reducing lateral deformation of liquefiable sandy foundation. The influence of saturation on lateral deformation is increasing evident with decrease of foundation depth.