Automated Real-Time Assessment of Stay-Cable Serviceability Using Smart Sensors

• Main Authors: Seunghoo Jeong, Young-Joo Lee, Do Hyoung Shin, Sung-Han Sim
• Format: Article
• Language: English
• Published: MDPI AG 2019-10-01
• Series: Applied Sciences
• Subjects: stay-cable; serviceability; monitoring; automation; real-time; raspberry pi; smart sensor
• Online Access: https://www.mdpi.com/2076-3417/9/20/4469

The number of cable-stayed bridges being built worldwide has been increasing owing to the increasing demand for long-span bridges. As the stay-cable is one of critical load-carrying members of cable-stayed bridges, its maintenance has become a significant issue. The stay-cable has an inherently low damping ratio with high flexibility, which makes it vulnerable to vibrations owing to wind, rain, and traffic. Excessive vibration of the stay-cable can cause long-term fatigue problems in the stay-cable as well as the cable-stayed bridge. Therefore, civil engineers are required to carry out maintenance measures on stay-cables as a high priority. For the maintenance of the stay-cables, an automated real-time serviceability assessment system using wireless smart sensors was developed in this study. When the displacement of the cable in the mid-span exceeds either the upper or the lower bound provided in most bridge design codes, it is considered as a serviceability failure. The system developed in this study features embedded on-board processing, including the measurement of acceleration, estimation of displacement from measured acceleration, serviceability assessment, and monitoring through wireless communication. A series of laboratory tests were carried out to verify the performance of the developed system.