Paper Abstract
This paper is dedicated to present the nonlinear behavior of spun-cast pre-stressed transmission poles subjected to uniform self-weight and the lateral point load applied at the top free end. To obtain the corresponded capacity curve of the pole, static nonlinear analysis (Pushover) is employed. A 15m-height transmission pole with a circular cross-section is considered in this study. In this study, nonlinear behaviors of the pole with different capacities are investigated as well. To apply the nonlinear finite element model, an efficient co-rotational tapered displacement-based beam-column element recently defined in OpenSees software is utilized. It is obvious that large deformation and rotations are considered using a co-rotational scheme. To trace the related equilibrium paths, Displacement Control Method (DCM) is employed. Due to fully numerical integration, the structure is divided into eight segments and conclusively nine Newton-Cotes integration points are used. In order to model pre-stress strands through the pole, the initial strain technique is used for an elastic perfectly plastic element, which can be only subjected to tension loads. Moreover, four different values are considered for pre-stressing force. All geometric and material properties of the pole structure are defined in the OpenSees software. Finally, the equilibrium paths of the poles are provided.