In response to the key issues of the lack of application of large gantry cranes and the technology for lifting thousand-ton class caissons in the construction of the gravity wharf project at Nansha port,Guangzhou Port,an efficient connection technology between the gantry crane and the caissons is proposed,and the new construction method is explored and practiced.Given that there is no domestic precedent for using large gantry cranes to batch-lift thousand-ton class caissons,and that achieving this lifting process requires overcoming the efficient connection technology between gantry cranes and caissons,a new construction method suitable for the transportation of large caissons onto barges is developed by using self-designed special lifting gear,and by utilizing the existing recessed harbor basin and 2，000-ton class large gantry cranes to replace the traditional temporary transportation wharf facilities.The research results show that this method directly saves the construction cost of the dedicated transportation wharf,effectively avoids the approval cycle for the temporary transportation wharf shoreline,and the cost of a single project is reduced by more than 30%.At the same time,as the gantry crane can operate all-weather and is not affected by tides and water levels,the efficiency of caisson transportation is increased by more than 40%,saving at least two months of construction time.