- 标题
- 摘要
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- 实验方案
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Fiber Optic Sensors Based on Photoacoustic Effect for Rebar Corrosion Measurement
摘要： An all-optical ultrasound sensing system based on photoacoustic principle is developed to monitor and investigate the initiation of early stage steel rebar corrosion in real time. The ultrasound generator was developed by small size gold nanocomposites coated optical fibers to generate 8-MHz bandwidth signals. The ultrasound receiver was applied by a fiber Bragg grating sensor. This system was employed for the first time as a disruptive approach in order to replace the application of conventional electrical-based sensors due to their unique advantages including miniature size, lightweight, immunity to electromagnetic interference, resistance to corrosion, and distributed sensing capability. Accelerated corrosion tests were conducted on steel rebars to validate the developed sensing system. The obtained results indicated that the mass loss of corroded steel rebars was characterized by the centroid frequency shift of measured ultrasound signals. The correlation between the centroid frequency shift and the mass loss depicted an exponential relationship.
关键词： photoacoustic (PA) principle,fiber optic sensor (FOS),frequency shift,Corrosion monitoring
更新于2025-09-23 15:22:29
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Feasibility of Distributed Fiber Optic Sensor for Corrosion Monitoring of Steel Bars in Reinforced Concrete
摘要： This study investigates the feasibility of distributed fiber optic sensor for corrosion monitoring of steel bars embedded in concrete. Two sensor installation methods are compared: (1) attaching the sensor along the bar and (2) winding the sensor on the bar. For the second method, optical fibers were winded spirally on steel bars with different spacings: 0 mm, 2 mm, 5 mm, and 10 mm. Steel bar pull-out testing was conducted to evaluate the effect of presence of distributed sensor on the bond strength of steel–concrete interface. Electrochemical testing was carried out to assess the influence of the installation methods on the corrosion resistance of the reinforced concrete. Winding the optical fiber on steel bars with a 10-mm spacing does not affect the bond strength and corrosion resistance and allows real-time corrosion monitoring. The distributed sensor data can be used to estimate the corrosion induced steel loss and predict concrete cracking.
关键词： distributed fiber optic sensor,installation,pull-out test,steel mass loss,corrosion monitoring,expansion strain,electrochemical test
更新于2025-09-10 09:29:36
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An overview of corrosion defect characterization using active infrared thermography
摘要： Corrosion is considered a destructive phenomenon that affects almost all metals. There is a variety of corrosion monitoring and measurement techniques being deployed across industries. However, very few techniques are ideally characterised with non-contact, non-intrusive, on-line and direct features for measuring the accurate corrosion rate or actual metal loss. Infrared Thermography (IRT) allows the recording of electromagnetic waves emitted from objects by using an infrared imaging system, such as an infrared camera. IRT is an online method of Non-Destructive Testing (NDT) meaning the delays in receiving results from a laboratory experienced in many NDT techniques can be eliminated. It is non-intrusive which means no process disruption and downtime will be imposed to the production line. It is also a non-contact method which mitigates the hazard occurrence and need for highly experienced personnel.
关键词： Infrared thermography,Non-destructive testing,Corrosion monitoring,Structural health monitoring,Image processing
更新于2025-09-04 15:30:14