The phase I project of Chizhou Chang-jiu Limestone Mine Wharf is located on the right bank of the Yangtse River with 7 berths in total.High pile wharf is designed with cast-in-place rock socketed pile.However，the bedrocks of the 6 and 7 berths are limestone with developed karst，and shallow in river bottom overburden with bare rock in some areas.And high environmental protection requirements for the finless porpoise protection area.In view of this complex working condition，the composite construction technology is adopted with combining through floating platform with fixed platform，the construction method was successfully solved the technical problems of cast-in-place rock socketed pile with shallow overburden，and accumulated valuable experience for similar projects.．