A novel technology of drainage casing pile is introduced.Its principle lies in the combination of the pile and the blind ditch drainage which provides drainage passages around piles.Anti-liquefaction effect is accomplished through efficiently reduce the excess pore water pressure accumulated in soils around piles when the earthquake occurs.The comparison of static-dynamic numerical simulation between drainage casing pile and the routine piles without blind ditch drainage is carried out.The numerical results show that the bearing capacity of drainage casing piles is close to that of conventional piles of equal diameter

which indicates that the pile bearing capacity doesn’t decrease as a result of the installation of blind ditch drainage.Conversely

the blind ditch drainage significantly reduces the excess pore water pressure induced by seismic liquefaction

and as a result of which

the effective vertical stress in pile peripheral soils is increased.Thus liquefaction is effectively prohibited.