| Transmission tower-line is a type of wind-load-sensitive structure , and wind load is the main control load. At present, the studies of the wind load model on the system, the response regulation and disaster induced by wind load are still at the initial stage. Therefore, based on the two-circuit 1000kV UHV power transmission line under planning, the wind load model on the steel tube tower, the wind-induced vibration character, the aeroelastic wind tunnel test of the tower-line coupled system and the estimate of the fatigue cumulative damage caused by wind-induced vibration are discussed as follows:(1) The wind load spectrum is formulated through the HFFB test. The shape coefficient of the two-circuit UHV steel tube transmission tower is obtained by the three-component-force test; and after the resonance response in the results of the HFFB test of the semi-rigid model of the lattice type tower is filtered, the foundation moment spectrum in the along-, cross-wind and torsion direction under different wind angles is fitted to formulation. Assumed that the coherence of the wind load in vertical is the same to the wind speed, the auto power spectrum and cross power spectrum of the wind load on the tower is formulated. Futhermore, the analysis shows that the contribution of the turbulence is about equal to the vortex shedding for the cross-wind motivation.(2) The wind-induced vibration of the steel tube transmission tower-line coupled system is studied by the aeroelastic wind tunnel test. The aeroelastic model is designed and made by the semi-rigid segment and U shape spring, and the checking result shows that the aeroelastic model meets the requirments of the wind tunnel test. As the tower and conducting cable can not use the same scaling factor, the distorted model is proved by numerical analysis. The character of wind-induced response of the the tower and tower-line system is summarized from the results of wind tunnel test, and the structure's natural characteristics and the input motivation is obtained from response inversion.(3)After building the finite element model of the tower-line coupled system, the analysis is conducted in both time-domain and frequency-domain numerically, and the response rules of single tower and tower-line system agree well with the results obtained from aeroelastic model tunnel test. The stiffness- and mass-matrix of the three-node- cable element and the insulator element considering the swing stiffness are deduced. With the assumption of equivalent linearization, the systems wind-induced respons are analysized in frequency-domain, and the result shows that the analysis in frequency-domain is accurate while the cable is tensioned and the sag is small.(4) The equivalent static wind load is calculated by the load combination method and wind vibration coefficient method respectively, and the suggestion is advanced for the consideration of cross-wind load in the design. The results of the test indicats that, the wind-introduced responses in the along-wind direction equals to that in the cross-wind direction. In consideration of equivalent static wind load in the cross-wind vibration, the generalized gust factor and wind vibration coefficient are introdued to calculate the cross-wind vibration in design.(5) Based on the liner fatigue cumulative damage theory, the transmission tower's fatigue life under wind-indced vibration is calculated in the time-domain and frequency-domain, and the process and method for the analysis of the tower's wind-indced fatigue is proposed. By the time-history analysis of the tower structure and rain-flow method, the fatigue cumulative damage is calculated in time-domain. According to the comparison of differernt existing methods in frequency-domain, generally all of the methods are conservative in estimation of the fatigue life, and the result of equivalent stress method is silmilar to that of the rain-flow method. Because of its simplify in calculation, the equivalent stress method is more suitable in transmission tower's total life cycle design.
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