| Power as a major energy carrier plays an important role in national economic construction. Transmission tower is not only an important part of power transmission system, the carrier of high load power transmission, but also an important lifeline engineering structures. Various natural calamities will cause the transmission tower capacity appear crushed, damaged by the power of pull, bad twist, tower break and so on. Once the transmission tower is destroyed in the pressure of catastrophe load, it will result in not only huge economic losses, but also secondary disasters like fire, it will also have great difficulties for incident recovery. Therefore, it has an important significance for us to monitor the structure of the security status of the transmission tower. FBG sensing technology has a strong anti-electromagnetic interference capability and it is light weight, corrosion resistance, minor signal attenuation, high accuracy, good stability and long service life and other physical properties. It also has a quasi-distributed sensing features, especially for the large-scale structure’s real-time monitoring needs of multi-parameter. We use FBG sensing technology to realize the real-time online monitoring of a transmission tower on the structural safety. The main contents of this paper are as follows:(1) Through finite element analysis software ANSYS, this paper established a linear transmission tower model. To simulate the impacts of disasters of geological structure and road icing hazards on linear transmission tower, gravity loads in different dip angle is applied to linear transmission tower; and vertically downward concentrated tensile load is applied to the cross arm edge of linear transmission tower Through analyzing the distribution of the deformation and stress, we found the position of significant deformation and stress concentration occurring.(2) According to the results of the finite element analysis, we use FBG strain sensor and FBG earth pressure sensor to monitor the transmission tower structures and identified exactly installation location of the sensor. We analyzed how the FBG strain sensor and FBG earth pressure sensor works, and through the universal tension and compression testing machine, we complete the calibration test. By putting up networks of transmission tower of fiber grating sensor and developing the fiber gratings on-line monitoring system of transmission tower structure, we realize the long-term real-time online monitoring of the structural safety of the transmission tower.(3) In order to filter out the measured noise, we use the weighted average fusion sequence analysis processing method based on standard deviation, for the 20 sample points’data we have collected within 1 hour by FBG strain sensors and FBG earth pressure sensor, we fused it on time sequence to give a fusion sequence value. Fusion sequence value of four FBG strain sensors are:55.68με,65.06με,75.14με,62.15με. Fusion sequence value of two FBG earth pressure sensor are:216.21Kpa,237.80Kpa. Fusion sequence obtained in this way is more accurate than the commonly used value of the arithmetic mean, it has high reliability and the resistance to errors are small.
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