| As an effective construction member, cable is increasingly used in the long-span spatial structures. Cable is a flexible member in the construction process different from other structures. So we must find effective way to monitor the force change of cable during the stretching process to ensure the safety of construction,and the final morphology and tensile properties is depends on the stretching process greatly. At the same time,cable will be subjected to the prestressing loss due to relaxation,so monitoring the force change of cable after the stretching process is very necessary.Based on the existing theory, monitoring strain and temperature with wireless monitoring system as well as exciting experiments, specifically as follows:1)The paper summarized the principal of the vibration-frequency method to measure cable force,introduced the linear vibration theory of cable, proposed the practical formulas to calculate the cable force considering the cable sag and bending stiffness effects,and designed corresponding calculation cases to verify the accuracy of the formulas.2) The paper participated in developing a new type of wireless sensor system to measure cable tension force,and introduced the development of wireless sensor networks, network topology, above all described the entire wireless sensor network systems,communication protocols and the final system configuration in detaily.3)Through the health monitoring of the Yueqing Sports Center, we proved the feasibility and superiority of the wireless sensor system that obtain the changing of strain and temperature.4) The paper illustrated the theoretical study of the test signal, introduced the Fourier transform of periodic functions and non-periodic functions,and then explain the discrete Fourier transform.Next introduced the structural dynamic parameter identification method with frequency domain and time domain respectively.Finally,we proved the the peak picking method is very good to verifying the force of cable.
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