Development of a new anchorage system for carbon fiber–reinforced polymer rods using extrusion process

Abstract

Carbon fiber–reinforced polymer (CFRP) rods have been considered as a candidate material for prestressed concrete applications because of their superior properties. For current applications, successful use of CFRP rods is linked to an efficient anchorage system design. This paper presents a newly developed anchorage system for CFRP rods and the design concept that the extrusion process is used to generate gripping force. The proposed anchorage system consists of a steel barrel and an aluminum sleeve, and an extrusion region is designed on the outside of barrel to generate a suitable contact pressure distribution on the CFRP rod. A mathematical model was proposed to estimate the contact pressure on the CFRP rod and the capacity of anchorage system. The simulation of extrusion and loading process was conducted with a three-dimensional (3D) finite-element (FE) model. The key design parameters of anchorage system were analyzed to obtain an optimized parameter combination. The experimental validation showed that the new anchorage system is capable of allowing the CFRP rod to attain the ultimate tensile strength.

A Novel Smart CFRP Cable Based on Optical Electrical Co-Sensing for Full-Process Prestress Monitoring of Structures

“…It consists of a new anchorage system and five CFRP bars, including three CFRP-steel wire composite bars, one CFRP-DOFS bar, and one CFRP-CCFPI bar. The new anchorage system is similar to that proposed in Reference [18], except that five CFRP bars can be anchored simultaneously instead of a single rod. The developed OECS-CFRP cable can not only measure the strain of CFRP cable in the normal use stage with high precision but also measure the large deformation of CFRP cable in the load-bearing capacity reduction phase with relatively low precision Firstly, a brief description is outlined for the production technology of the CFRP-DOFS bar, CFRP-CCFPI bar, and CFRP cable anchorage technology.…”

“…The proposed OECS-CFRP cable in this paper is assembled by three CFRP composite bars, one CFRP-DOFS bar, and one CFRP-CCFPI bar through the system, as shown in Figure 7. The anchoring system is developed on the basis of CFRP bar anchoring system in Reference [18], which is designed to grip the through radial contact pressure generated by the extrusion process of the me The anchoring system consists of an aluminum inner sleeve and a steel outer s inner sleeve has five holes with a diameter of 5.2 mm distributed in the shape blossom, and the five CFRP bars are passed through the holes, respectively. T DOFS bar and the CFRP-CCFPI bar pass through non-adjacent holes.…”

“…The proposed OECS-CFRP cable in this paper is assembled by three CFRP-steel wire composite bars, one CFRP-DOFS bar, and one CFRP-CCFPI bar through the anchoring system, as shown in Figure 7. The anchoring system is developed on the basis of the single CFRP bar anchoring system in Reference [18], which is designed to grip the CFRP bar through radial contact pressure generated by the extrusion process of the metal sleeve. The anchoring system consists of an aluminum inner sleeve and a steel outer sleeve.…”

“…The mechanical anchorage device is not suitable for multi-bar anchorage, and the sudden change of stiffness between the anchorage device and rods is easy to cause damage to CFRP rods with weak transverse strength. Shao et al proposed an anchorage system for a single CFRP rod based on cold extrusion [18]. The designed anchorage consists of a steel cylinder and an aluminum sleeve, and an extrusion zone is designed outside the cylinder to produce a suitable contact pressure distribution on the CFRP rod.…”