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In recent years, with the rapid development of China's national economy, the rational development and utilization of resources has made considerable progress. Especially in the boot of power resources, UHV transmission towers and lines its transmission capacity and efficiency characteristics are widely used. As the the important lifeline engineering of power facilities, the destruction of the transmission line system will lead to the paralysis of the power supply system, which not only seriously affected the people's production and construction, the order of life, and may lead to other secondary disasters. Transmission towers as the towering structure, wind load, leading to the destruction of one of the roles. Therefore, the transmission towers under wind loads on system reliability performance analysis becomes more important. This article (Monte-carlo), Monte Carlo method on a large crossing transmission tower system under wind loads static reliability analysis, the main contents are: wind load distribution function of the model as well as the characteristics and component materials. The resistance distribution model. Angles for transmission towers, due to its special shape, easy compression warp buckling, and reduce the carrying capacity of the member. In this paper, Ansys finite element analysis software SHELL181 unit angle steel model, and by applying the initial defects and initial residual stress modeling real steel nature, force analysis, the Angles buckling bearing capacity and instability bearing capacity - the relative displacement curve downward slope. The numerical analysis shows that the angle steel compression buckling member slenderness ratio, thickness ratio, loading mode, which member slenderness ratio as the main factors. Therefore, according to member slenderness ratio curve fitting Angles buckling and postbuckling bilinear failure model. Large transmission towers can be simplified main tower diaphragm, and to play a supportive role in the auxiliary tower head section thin rod processing tower space truss system model. Load case to consider the gravity of the tower, the guide, ground, insulators, etc., the 45 ° angle of the lateral tower wind loads and guide the ground wind loads. Wind load on the tower treated as average in each segment node, guide, ground wind loads the tower hanging nodes. Static analysis using Matlab program within the elastic range, the calculation results of the finite element model was built with the Ansys software compared, a difference of less than 5%, effective certification procedures. Calculated using Matlab software reliability analysis program preparation, tower truss system with hybrid system system reliability calculation. By the results of comparative analysis found mixed system more in line with the actual transmission Tate of truss system failure probability is greater than the model, a reliable indicator of a difference of about 0.44.
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