Effect of chamfering of cable clamp plate on shear behaviour of CFRP tendons

• Effect of chamfering of cable clamp plate on CFRP tendons was analyzed.
• Chamfering can increase the transverse shear strength of CFRP tendons.
• Chamfering can increase the transverse shear deformation of CFRP tendons.
• Mechanical mechanism and failure mode of shear plane were changed.
• Tendon still has transverse bearing capacity after shear failure by chamfering.

The use of carbon fibre reinforced polymer (CFRP) tendons instead of steel tendons is a promising method for improving the overall performance of beam string structures. However, research on the shear behaviour of CFRP tendons is insufficient. In this paper, the effect of chamfering of the cable clamp plate used in the connected joint between prestressed tendons and struts for beam string structures on the shear behaviour of CFRP tendons was analyzed. The transverse shear tests were conducted on 5-mm-, 7-mm- and 9-mm-diameter transverse enhanced CFRP tendons to investigate the effect of chamfering. Experimental results show that the chamfering increased the transverse shear strength of 7-mm-diameter CFRP tendons significantly (approximately 15%) and slightly (approximately 0–3%) improved the shear strength of the 5-mm- and 9-mm-diameter tendons. The transverse shear deformation of the three diameters of CFRP tendons increased by 35%, 77% and 92% compared with no chamfering effect. Another important result is that the mechanical mechanism and failure mode of shear plane for all specimens were changed by the chamfering. Complete cross-section fracture on the shear plane of CFRP tendons has not occurred, and the tendons can still have some transverse bearing capacity after shear failure.