Investigation on the structural failure behaviour of pultruded circular tubular GFRP multiplanar truss bridges with non-metallic connections through finite element modelling.

• FE models were developed for five different multiplanar truss bridges with non-metallic connections. • The FE models were able to predict the initial failure load and the nature of the member connection failure modes. • Parametric studies involving members with different diameter to thickness ratios and number of laminate wrapping layers at member connections were studied. The finite element (FE) method was used to investigate the failure of member connections of five glass fibre-reinforced polymer (GFRP) multiplanar truss bridges (MTB) with non-metallic connections. Three-dimensional FE models for the MTBs were developed and validated against previous experimental results and were accompanied by multiple parametric studies. Adhesive failure of the brace occurs progressively around the perimeter of the brace and GFRP laminate wrapping failure was not observed before adhesive bond failure of the brace. Furthermore, the failure sequence of the GFRP laminate layer and the adhesive bonding between the brace and chord was found to be dependent on the brace wall thickness. Extent of the predicted fibre tensile rupture of the GFRP laminate was greater for cement mortar grouted GFRP rods than its non-GFRP grouted counterpart. [ABSTRACT FROM AUTHOR]