Bi-axial behaviours of abraded and rehabilitated FRP decks as anisotropic plates under concentrated wheel loading

Nonlinear behaviour of pultruded decks due to morphing of tyre loads

“…The pultruded FBD600 cellular GFPC deck, used on the Mount Pleasant, West Mill and Frampton Cotterell bridges in the UK [6,22,23], is employed to illustrate the key points of this study. Fig.…”

“…In some cases [19,25,34] the entire loading setup comprising plate, pad and other components has been included in the FE model, so that the contact pressure distribution appears implicitly in the model. These previous FE studies commonly observed various degrees of discrepancy between experimental measurements and numerical predictions on local strains and deflections as functions of load [7,20,22,24,25,29,32]. The discrepancies were reported to have their origins in material property uncertainties, boundary conditions, measurement error, recording location sensitivity and modelling assumptions.…”

“…For this reason, the tyre load's spatial definition (shape and size of the contact zone, and the pressure distribution on the deck over that zone) can significantly influence the induced local stresses in the deck. Along with in-plane shear stresses which can progressively damage fibre-resin interfaces, through-thickness stresses in and near the directly tyre-loaded top web-flange junctions of such decks are known [19,[22][23][24][25][26]32] to be sources of delamination, namely initiation of interface cracks, owing to the absence of through-thickness fibres which can significantly improve strength in this direction. This crack initiation is critical since it not only affects short term strength, but it also paves the way for moisture ingress that influences long-term behaviour such as FRP material degradation and fatigue performance.…”

“…Finite element modelling of local tyre load effects in FPC decks has seen a varied approach to spatial definition of the tyre load. These range from the simplified assumption of uniform contact pressure [12,16,17,18,20,28,29,32], to either trapezoidal [22,24] or nonlinear [26,32] representations of the profile assuming uniform contact pressure across the width of the tyre at each location. In some cases [19,25,34] the entire loading setup comprising plate, pad and other components has been included in the FE model, so that the contact pressure distribution appears implicitly in the model.…”

Characterisation of local damage in pultruded GFRP road bridge decks with random fibre mat misalignments

“…Note that the misalignments do not reduce the stress capacity of the material, rather they increase the local (normal and shear) stress demands along and near the misaligned fibre layer, which reduces the structural integrity of the junctions. Indeed, previous tests have shown that the misaligned fibres dominate the failure behaviours of the junctions in pultruded decks [8][9][10][11][12][13][14][15] and in I-sections [16][17][18][19][20][21], which in turn has led to serviceability problems for FRP decks on the road networks in different countries [22,23]. For FRP components used in the aerospace, automotive, renewable energy and marine domains, such as stiffened panels employed in aircraft, F1 cars, wind turbines and yachts, these misalignments and their associated knock-down effects have been extensively studied [24][25][26][27][28].…”