The study on prestressed cable stress based on brillouin-optictime optic fiber sensor

The Brillouin-optic time domain reflectometer (BOTDR) fiber strain sensing technology has been used in the optic fiber and its attachment surface supporting for the axial strain distributed monitoring, A stress test monitoring is respectively on a steel hinge cable line with the three arylene fiber-reinforced plastic (AFRP) anchor, and the distributed contingency sampling point has the minimum distance of 5cm. Test results show that distributed optic fiber sensor has a high accuracy. The relative error between optic fiber sensors and strain measurements is less than 3.8 percent. In the stage of tensing anchors, a steel cable hinge line´s prestressed loss is 8.8 percent; three AFRP anchors´ prestressed loss is less than 6.08 percent. After a month, the steel cable hinge line´s prestressed loss is 11.1 percent; AH cable prestressed loss is less than 10.3 percent.