Abstract:Pneumatic DTH(down the hole) hammer drilling has the characteristics of fast construction speed,high efficiency,reliable quality,high cost-effectiveness,small equipment footprint and green environmental protection without mud,especially suitable for drilling in areas with ultra-thick riprap layer,but it is less applied in the field of port engineering.The pipe rack foundation project on an embankment of a petrochemical terminal in a port project used the traditional punching and cast-in-situ pile scheme,which has very low construction efficiency and could not be completed as scheduled with quality.The construction process with long spiral pneumatic DTH hammer assisted PHC pile sinking is introduced innovatively,which greatly improves the efficiency of pile sinking,shortens the original 29 months construction time to 2.5 months,and ensures timely completion to meet the overall project schedule requirement.Simultaneously the technology reduces material and construction costs,and effectively solves engineering problems,ensuring smooth and timely completion of projects.