Comparative study on strengthening methods of steel towers

Abstract

Steel towers are widely used in the telecommunication and power transmission sectors. Failure of these towers causes direct and indirect losses and disruption to the services provided by those towers. As a result, industries and general public face difficulties and the productivity of the country also gets affected. Considerable number of tower failures has taken place in both power transmission and telecommunication sectors of Sri Lanka in the recent past but only a little amount of studies has been done so far. Testing at least a tower in a transmission line is mandatory in the power transmission sector of Sri Lanka. Generally these tests are carried out at the Structural Engineering Research Centre in Chennai. It has been observed that several towers fail prematurely under normal loading conditions during full scale tests, indicating lack of strength of towers. The objectives of this study are analysing tested towers using finite element method and comparatively studying different techniques of strengthening of towers. A general purpose finite element analysis program SAP2000 was used for the modelling and analysis of towers. Finite element model of a tower which has been tested to full scale was developed and validated in SAP2000. Then different methods of strengthening were carried out to the validated model to comparatively study the effect of each method on the strength of the tower. The findings are presented in this paper.