The Application Of Bolted Channel Steel Reinforcement Technology In Transmission Lines Against Typhoon

In order to study the application of bolted channel steel reinforcement technology in transmission tower reinforcement Concerning the hurricane accident occurred frequently in transmission lines under typhoon,a finite element model of a multi-tower-line system,which based on typical tower structure of a 220 kV transmission line in Guangdong province,is established in this paper.this paper analyzes the stress and reinforcement under typhoon load and studies the effect after reinforcement.The main research contents and results are as follows:(1)According to the actual transmission line of China Southern Power Grid,the finite element model of the transmission tower line coupling system is established,and the modal analysis of the finite element model of the transmission tower is carried out to verify the applicability of the model,and simulate the generation of typhoon loads.Through the dynamic response analysis of the model under typhoon load,the weak part of the tower is found,which provides the basis for the reinforcement analysis of the subsequent chapters.(2)This paper introduces the characteristics of the bolted channel steel reinforcement technology compared with the traditional reinforcement technology,and then compares and analyzes the characteristics of the three connection methods of the bolted channel steel reinforcement technology,and gives the optimal connection method.The selection table of the reinforcing channel section of the common angle steel is given.The weak part of the transmission tower is reinforced by this connection method,and the force analysis of the transmission tower line system before and after reinforcement under the typhoon load is carried out.(3)The stability of the transmission tower under different working conditions before and after reinforcement is analyzed,and then the reliability calculation of the transmission tower is carried out under different typhoon loads.The results show that the stiffness distribution of the transmission tower finite element model established by the truss beam hybrid form is more in line with the actual situation of the structure;under the action of strong typhoon,the weak part of the whole tower will appear in the tower body and the tower leg,which should be Wind tower main material for wind-resistant reinforcement design;The reinforcement design of the weak part of the transmission tower by bolted channel steel can greatly improve the bearing capacity of the original tower angle steel member and the wind stability of the tower structure.The bucklinganalysis of the example shows that the buckling coefficient of the iron tower is doubled before the reinforcement,and the weak part of the tower is transferred to the tower head section after reinforcement.The reliable analysis of the transmission tower found that the reliability index of the transmission tower after resisting the super strong typhoon was significantly improved compared with that before the reinforcement.When the basic design wind speed of the area is greater than the basic wind speed of the twelve-level typhoon,the effect of the wind-resistant reinforcement of the transmission tower on improving the wind-resistance reliability is more significant.At the same time,the analysis shows that according to the current design specifications of the transmission line,the construction of the southeast coastal area of China The ability of transmission towers to resist super typhoons is insufficient.Through the research,it is found that the reinforcement of transmission tower by bolted channel reinforcement technology can significantly improve the wind-bearing capacity and stability of the transmission tower under the action of strong typhoon.It has good reinforcement effect in the anti-typhoon reinforcement design of transmission line and Application prospects.