Construction Technology of Long Spiral Drilling Grouting and Self-weight Pile Planting for Prestressed Pipe Piles
Aiming at the problem that the conventional prestressed pipe pile construction method is limited in the bottom of foundation pit,the method of pre-pilot hole grouting and pile planting at the pile position is put forward.By integrating the grouting system with the long spiral drilling rig,the synchronous grouting construction of the long spiral air jet drilling pilot hole and the lifting drill pipe is realized.After the cement slurry hole is formed,the prestressed pipe pile is implanted into the cement slurry hole by self-weight,and finally it is sent to the bearing layer at the pile end by the vibrating hammer and the pile feeder.The organic combination of pipe pile and cement slurry forms a high-strength cement-soil composite pipe pile,which will significantly improve the bearing capacity of the pile body,meets the normal development of construction,and ensures the quality of pipe pile planting.