Failure analysis on skunk-arm of electrical tower

Abstract

Un-proper procedure during installation of the wire-rope could introduce unusual loading to the skunk-arm of the highvoltage electrical tower. Understanding of structural behavior of this kind of structure under different loading should be helpful to take preventive measure again possible future accidental cases. Static and buckling analyses have been performed using Finite Elements Analysis (FEA). Skunk-arm structure modelized by one-dimensional elements, combination between bar and beam. Beam elements represent main structure that are flexural members and bar elements represent stiffener that can only be in tension or compression loading. Stress distribution due to maximum static loading did not show an excessive stress value, it means no yielding occurs in the structure. But buckling factor show the maximum loading is close to the critical loading that may provoke collapse of structure in buckling mode. The result show the mechanism of structure failure, which begin with buckling of the lower members of the skunk. In normal condition, factor of safety of 2 is taken according to maximum loading of the structure.