Tehnički vjesnik, Vol. 27 No. 6, 2020.
Izvorni znanstveni članak
https://doi.org/10.17559/TV-20191108160438
The Effective Flexural Modulus of Filament Wound GRP Tapered Poles
Ana Skender*
orcid.org/0000-0003-3955-832X
; University of Zagreb, Faculty of Civil Engineering, Fra Andrije Kačića-Miošića 26, 10000 Zagreb, Croatia
Zoran Domitran
orcid.org/0000-0003-0626-1685
; University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture, Ivana Lučića 5, 10000 Zagreb, Croatia
Jakov Krokar
; University of Zagreb, Faculty of Civil Engineering, Fra Andrije Kačića-Miošića 26, 10000 Zagreb, Croatia
Sažetak
The composite lighting poles are filament wound GRP tapered tubes with a variable wall thickness across the length. In this study, the effective flexural properties of GRP poles have been determined, experimentally and theoretically. Cantilever bending tests were performed on full-scale GRP tubes and the effective flexural modulus was calculated from the initial slope of the flexural stress-strain curve based on the classical beam theory. The results show that the strain range corresponding to the linear behaviour is the same as under three-point and four-point tests with smaller specimens. Unlike other methods, the proposed method considers the variation of the crosssectional properties across the pole length. The effective properties of GRP tubes were further determined considering the orthotropic and unsymmetrical layup of the wall segment. A sensitivity analysis was performed at the lamina as well as the laminate level in order to evaluate the influence of material properties of the matrix and the fibres, the amount and orientation of the fibres as well as the layer thickness. Finally, the effective (replacement) flexural modulus of a filament wound tube was determined based on the classical lamination theory and compared to experimentally determined values. It was concluded that the replacement flexural modulus is a matrix dominated property highly influenced by the fibre volume fraction.
Ključne riječi
cantilever bending test; classical beam theory; classical lamination theory; effective flexural modulus; fibre reinforced polymer pole; filament winding; tapered tube
Hrčak ID:
248225
URI
Datum izdavanja:
19.12.2020.
Posjeta: 2.163 *