Performance of Fiber-Reinforced Plastic Tapered Poles under Lateral Loading

Abstract

An extensive research project is currently being carried out at the University of Manitoba to develop lightweight poles for use in transmission lines. In this project, the failure modes of tapered fiber-reinforced plastic (FRP) poles with hollow circular cross-section subjected to cantilever bending are being investigated experimentally and theoretically. The poles are made of vinylester reinforced with E-glass fibers and are produced by the filament winding process. To date, twelve bending tests have been conducted on scaled poles up to failure. Test parameters included the wind angle, and the number of layers. Local buckling and/or material failure, very likely to appear in thin-wall cross-sections, are also investigated. The analysis was conducted through a nonlinear finite element program using superparametric layered cured shell element. The coupling phenomenon between flexural bending and in-plane stretching and the effect of shear deformation were included in the finite element model. The analytical results obtained in this study are compared to experimental results obtained for various thickness and reinforcement specimens of composite poles. The finite element model was used to design a series of FRP poles with different safety factors.

Finite Element Modeling for Deflection and Bending Responses of GFRP Poles

“…The finite element method is employed to analyze the different proposed models for 20, 33, 35 and 40 ft GFRP poles. These models were proposed according to the survey in the literature review of experimental data from several sources [1,3,[5][6][7][8] for different combination of parameters such as fiber orientation, number of longitudinal and circumferential layers, layer thickness and type of fiber. The details of the new proposed design are given in Tables 8 and 9 for 20, 33, 35 and 40 ft GFRP poles.…”

“…Twelve FRP poles were tested by Polyzois et al [5]. These FRP poles were subjected to cantilever bending and three different modes of failure were observed.…”

Full-Scale Flexural Testing on Fiber-Reinforced Polymer (FRP) Poles

“…While studies have addressed the material failure and buckling of thin-walled sections such as I-beams, box beams, etc., made from composite materials [5], very few studies have been conducted on the Behavior of tapered sections [6].…”

“…Experimental and analytical studies were carried out [6] to validate the predicted ultimate loads for tapered filament wound FRP scaled poles subjected to cantilever bending. The specimens were 2500 mm in length; the inner diameters at the base and the top end were 100 mm and 74 mm, respectively.…”

“…The same performance of FRP poles having high fiber volume fraction can be achieved by using less fiber volume fraction but with changing the fiber orientation towards the longitudinal direction [6] and the incorporation of circumferential layers tend to increase the critical ovalization load [10]. More tests, however, are required to determine the optimum values of fiber angle and fiber volume fraction.…”