The sling anchorage: Approach to anchor the full load bearing capacity of pin-loaded straps

Tension members are a promising application for carbon fibre reinforced polymers (CFRP) in civil engineering. Anchoring CFRP tension members is a significant challenge due to their relatively low strength and low Young's modulus in the transverse direction. The laminated loop anchorages of pin-loaded straps are strong and lightweight force locking connections. However, the load bearing capacity of those anchorages is limited to about 70 % of the tension members' breaking load due to the superposition of tension and bending stress at the pin. In this paper, an alternative design for pin-loaded straps (the sling anchorage) is proposed that increases the load bearing capacity up to 100 %. This increase is predicted using a theoretical approach from the literature. Numerical and experimental results are presented to characterize the structural behaviour of the sling anchorage. The experimental results show that the sling anchorage can achieve the predicted load bearing capacity. Furthermore, a manufacturing method that allows forming the sling anchorage at the ends of parallel CFRP tapes (or pultruded profiles) is also introduced.