English：

PHC pipe pile has the advantages of high bearing capacity, fast construction speed, goodconstruction quality and low project cost. Therefore, it is widely used in engineering construction.However, due to the bearing capacity of the foundation, the strength of the PHC pipe pile is often notfully utilized, resulting in a waste of resources. Pile⁃end post⁃grouting is a very effective method toimprove the bearing capacity of the foundation. Firstly, the grouting pipe is set up by using the cavity ofthe PHC pipe pile, and the pile tip with grouting function is installed at the pile end to form a groutingloop in the PHC pipe pile. Then, the PHC pipe pile is piled in place. Finally, the high⁃pressure cementslurry is injected into the PHC pipe pile end through the grouting circuit to reinforce the soil at the pileend and the pile side to improve the bearing capacity of both the foundation soil and the pile foundation.To realize the post⁃grooming of the PHC pipe pile end, the built⁃in grouting pile tip of the grouting deviceis developed. The experimental research and engineering application show that the built⁃in grouting piletip of the grouting device is technically feasible, and the post⁃grouting PHC pipe pile has the advantagesof a simple process, simple equipment, remarkable effect and low cost.