ABSTRACT
Fiber Bragg grating (FBG) sensors emerged as a relatively new strain-sensing technology for civil engineering applications. Based on the theory of FBG technology and bi-directional loading test method, the field test was conducted on bi-directional loading tests of two pre-stressed high-strength concrete (PHC) pipe piles to investigate the behaviors and performance of PHC pipe piles. The strain along the pile shaft was monitored by FBG sensors. The axial forces, pile-soil relative displacement and shaft resistance were calculated based on the measured strain to verify of applicability of FBG sensors in bidirectional loading test of PHC pipe piles. The FBG sensing technique satisfies the bidirectional O-cell test accuracy and design requirements of PHC pipe piles. These results provide a reference for similar engineering applications and describe a new testing technology for PHC pipe piles in complex environments.
