Design of corrosion sensor for prestressed anchor cable
Corrosion degree of prestressed anchor cable is closely related to the structure safety,but there is no effective monitoring method.Considering that the occurrence of corrosion is closely related to the pH change of the surrounding environment.The corrosion sensor selects HEM A-A A hydrogel as the sensitive material and combines the transmission advantages of fiber Bragg grating(FBG)for design.The sensor is designed to identify the pH value change caused by the invasion of corrosive medium when the grouting part is pulled and cracked,and make an early warning when the anchor cable is facing the threat of corrosion.The test results show that the measuring range of the sensor is pH 4～11,the sensitivity is 25 pm/pH,and the correlation coefficient is 0.997;Compared with the bare fiber,it is found that the coating of hydrogel does not bring significant changes in the temperature characteristics of fiber grating,and the sensitivity is 9.5 pm/℃.The performance of the test simulation sensor for continuous monitoring in the environment is relatively stable.If the limitation of the dry and wet cycle of the application environment is considered,the combination degree of the hydrogel and the fiber grating needs to be improved.The purpose of corrosion monitoring can be achieved by setting corrosion sensors in the anchor cable.
anchor cablecorrosion sensorfiber gratinghydrogelpH value
万方数据
维普
