Static Experimental Study on New Arc Multi-Tendon CFRP Cable Anchorage System

CFRP has the potential to replace steel cables in large-span cable-stayed bridges due to its high strength and lightweight material properties. However, the weak lateral force performance of CFRP material creates the challenge of anchoring. This study introduces a new inner cone + arc + straight cylinder bond-type anchorage system to optimize CFRP tendons' force state. Experimental and finite element analyses verified the new anchoring system's performance. In static load tensile tests, six groups of seven CFRP tendon anchorage systems with different sleeve grooves were used to study the failure mode and load-strain variation law. The difference in mechanical properties between the new and traditional anchorage is evaluated in the finite element analysis. The results indicate that the new anchorage system can lower the stress concentration in the anchorage zone and enhance anchorage performance. The groove design of the sleeve can effectively increase the anchoring efficiency, where the groove depth is proportional to the anchoring efficiency and the groove spacing is inversely proportional to the anchoring efficiency. The magnitude of the stress inhomogeneity in the multi-tendon anchoring system during tensioning is proportional to the beginning conditions and the load size. When the inner wall of the sleeve becomes more abrasive, the force heterogeneity of the anchorage system reduces. The tests and finite element analysis show that the new anchoring may improve stress distribution and anchorage efficiency. In engineering practice, it can be utilized as a dependable anchorage system.