The Development Status of Large Diameter PHC Pipe Pile Sinking Construction Technology

Large diameter PHC piles with diameter over 800 mm have high vertical compressive bearing capacity and good lateral stability. The sinking pile construction technology of large diameter PHC pile has outstanding effect in guaranteeing high efficiency, low cost and green and low carbon, which is the key to realize the large-scale promotion of large diameter PHC pile. In this paper, the development and application status of large diameter PHC pile using hammering method, static compression method, assisted pile sinking method, drilled pile sinking method and other pile sinking techniques are sorted out, and combined with the engineering cases, the diameter of construction piles of different working methods, applicable stratum, technical advantages and problems are summarized. From the current development situation, the resistance of large diameter PHC piles constructed by soil squeezing method increases significantly with the increase of pile diameter, which leads to difficulties in pile sinking, fewer applicable strata and generally shorter pile length. The drilling method can effectively reduce the resistance of large diameter piles and improve the applicability in hard ground and complex combination of ground, that is a very potential direction for the development of large diameter pile construction technology. However, the drilling method needs to solve the problems of drilling efficiency in hard ground, as well as reducing construction cost and environmental impact.