Numerical simulation of full-scale tests in transmission line towers

Resumo

Transmission line towers are structures designed to carry electrical energy from generating stations
to consuming centers. Full-scale tests are traditionally employed in designing verification of transmission line
lattice tower structures. Due to the cost of these tests, an alternative is to evaluate their structural behavior using
numerical methods. In the present work, a nonlinear analysis method is presented for predicting the ultimate
structural response of two steel lattice towers under static load conditions. In the proposed technique, each tower
is modeled as an assembly of beam-column elements. The solution scheme consists of an incremental-iterative
predictor-corrector strategy based on the arc-length method. Linear, geometric and plastic matrices are used to
describe the structure behavior in an updated Lagrangean framework. A lumped plasticity approach coupled with
the concept of yield surfaces and plastic hinges is adopted for modelling material nonlinearity. Based on the results,
it was verified that the proposed model can produce accurate results to simulate load and failure modes of steel
lattice towers. However, some inaccuracies may arise in predicting the collapse load when failure occurs due to
elastoplastic buckling of the members.