Experimental Research on Shear Capacity of PHC Pipe Pile Strengthened with CFRP

In order to improve the insufficient shear capacity of prestressed high strength concrete (PHC) pipe pile head after pile cutting, two reinforcement measures of internal filling concrete core and external wrapping carbon fiber sheet (CFRP) were considered respectively, and the static load test of shear bearing capacity of five full-scale PHC pipe pile specimens (PHC 400 B 95) was completed. The data of cracking shear force, ultimate shear force, failure mode and pile strain deformation were obtained, the enhancement effects of different reinforcement measures on the shear bearing capacity of PHC pipe pile specimens were analyzed, and the reliability of the calculation results of the formula of shear bearing capacity of pile head strengthened with carbon fiber sheet was verified. The results showed that compared with PHC pipe pile with concrete core filling, carbon fiber sheet had better effect on strengthening the shear bearing capacity of pile head after pile cutting, and the shear failure mode of pile head changed to bending failure mode, which delayed the cracking and crushing of pile head concrete and improves the ductility of pile head; according to the analysis of test data, the formula of shear bearing capacity of pile head strengthened with carbon fiber sheet was put forward. The calculation results were safe and reliable, which could be used in engineering design.