FIELD EXPERIMENTAL STUDY OF LOAD TRANSFER MECHANISM OF GFRP ANTI-FLOATING ANCHORS BASED ON EMBEDDED BARE FIBER BRAGG GRATING SENSING TECHNOLOGY

Based on the pull-out destructive field test of three full-thread GFRP anti-floating anchors, with successfully applied embedded bare fiber Bragg grating sensing technology to pull-out tests on GFRP anti-floating anchors, the load-bearing characteristics, load transfer characteristics and failure mechanism of GFRP anti-floating anchors have been studied. The results show that the embedded bare fiber Bragg grating sensing technology has its unique superiority, and will not cause damage to GFRP anti-floating anchors. The GFRP anti-floating anchors basically experience shear failure. The ultimate uplift capacity of GFRP anti-floating anchors with an anchorage length of 5.0 m and a diameter of 28 mm is 400 kN, which can satisfy engineering demands. The axial stresses of anchors are mainly concentrated in the area of about 3.0 m away from the bolt hole top, which decrease with the increase of anchor depth. The peak value of shear stress appears about 0.8 m under the bolt hole top, while the peak value of shear stress curve increases gradually and moves to deeper location with the load increase. According to the test results, the failure mechanism of GFRP anti-floating anchors is further analyzed. The research results can provide theoretical basis for application of GFRP anti-floating anchors.