Dynamic Analysis Of Power Transmission Tower Collapse With Wind Load

In recent years, with the development of national economy, power industry develops very quickly.Transmission line play an important role in the operation of a reliable electical power system.transmission is becoming taller,and the transmission line span is getting bigger and bigger. Transmission tower withstanding more string load and the wind load. Transmission tower get more soft.The current design of transmission tower under wind loads is calculated according to the static load, Conductors and transmission towers and structures are often designed separately,the conductors designed by electric professional engineer,which provide wire load to structural engineer. Usually only consider the role of wire static load and ignored conductors and transmission tower with coupling, this method is not reasonable.Transmission tower collapses in adverse weather conditions now and than,which always accompanied thunderstorm.the downburst caused many accident in this weather condition.this paper studied the simulation of transmission collapse under downburst wind load.In this paper, the tower is modelled as an assembly of beam-column elements.four-node isoparametric curved element,and Prestressed pole unit simulation insulator,using bilinear Restoring Force Model to fomulate the Material nonlinear.Analyses the general characteristic of the downburst, And adopt the downburst decomposed into a time-varying average composition and the magnitude of a standard normal distribution function. Simulated downburst wind load time history samples,apply it as external load to the established transmission tower model. Consider the instability pressure transmission tower failure criteria, and the elastic-plastic dynamic analysis of power transmission tower.Analysis of transmission tower know that transmission towers destroyed in the lower part of the body of the Tower, compressive failure modes in the beam, causing transmission tower’s final tower. The result is similar to This full scale test of transmission tower.and Consistent with conclution that the menber failure at the smaller inner force by some Scholars.