STATIC TENSILE EXPERIMENT AND NUMERICAL ANALYSIS OF LAMINATED CFRP STRAPS

Pin-loaded laminated carbon fiber reinforced polymer (CFRP) straps are produced by winding unidirectional CFRP tapes around two separated pins, and the load is transferred by the pins. Axial tensile tests were performed to investigate the displacement and strain distributions in the individual layers, the crack propagation and the failure modes. A finite element model was developed and validated by the experimental results. Based on the experimental and numerical results, the effect of critical parameters on the load-bearing and failure mechanisms of the strap were analyzed. The analysis shows that the load transfer efficiency of CFRP straps was decreased by 20% compared to the straight strap. Brittle failure occurred at the intersection between the straight and the curved segments with the development of the delamination and longitudinal cracks. The curvature, strap thickness and friction coefficient had significant influence on the maximum stress of each layer, which always occurred at the intersection between the straight and the curved segments. The load bearing capacity and failure modes were greatly affected by the stress distribution in the curved segment even if the stress level was relatively low.