A Study On Cable Force Monitoring Wireless Sensor For Cable-stayed Bridge

The cable force monitoring of cable-stayed bridge is of the essence for the constructionmonitoring and structural health monitoring. The use of wireless sensing techniques on thecable force monitoring system will damatically reduce the costs and improve the efficiency ofmonitoring. In recent years, with the rapid development of sensing, wireless communicationand micro electro mechanical systems techniques, the application and popularization ofwireless sensing techniques have been promoted. Therefore, in view of the immaturity of thewireless sensing techniques for the cable force monitoring system, study and develop thewireless sensor for cable force monitoring is of significance and application value.The main work of this dissertation is addressed as follows:(1) The current research state and development of the cable force monitoring is firstreviewed. In view of the limitations of current equipments, the characteristics and applicationof the wireless sensor and Zigbee wireless communication protocol are further investigated.(2) The theoretical basis of cable force monitoring, i.e., signal processing theory,frequency-domain analysis method and cable force measurement techniques based on thefrequency method, are reviewed comprehensively. Furthermore, an intelligent recognitionalgorithm for identifing each natural frequency of the cable is presented.(3) The hardware design and integration for the wireless sensor of cable force monitoringare conducted. Based on the principle of miniaturization, low power consumption, low costand high reliability, the corresponding electronics components are compared and seleced.Moreover, make use of the design modulization method, the sensing module,micro-processing module, wireless communication module and energy supply module aredesigned and debugged.(4) Based on the software design principles and functional requirements, the software forthe pre-processing, signal processing, cabel force computational analysis and post-processingare densigned and implemented. In addition, the software flow and the correspondingoperation interface are presented in detail.(5) Take a simply cantilevel beam as experiment example, the sensitivity, accuracy androbustness against noise of the wireless sensor are validated. On the basis of the research conducted in this dissertation, the cable force monitoringwireless sensor based on the Zigbee wireless communication protocol, which has the fullfunctionality of wireless data acquisition, intelligent identification of each natural frequencyand accurate transformation between frequency and cable force, can be further developed.This wireless sensor can damatically reduce the costs, improve the efficiency and furtherprovides important basics for the development of structural health monitoring system withwireless and real time.