A Split-Wedge Anchorage for CFRP Cables: Numerical Model vs. Experimental Results

Area of Science:

• Civil Engineering
• Materials Science
• Structural Engineering

Background:

• Fiber-reinforced polymers (FRPs) offer high strength, stiffness, and environmental resistance, making them suitable for civil structural applications.
• FRP cables are increasingly considered for prestressing systems as alternatives to traditional steel cables.
• The inherent brittleness of FRP materials presents challenges in designing reliable anchorage systems to prevent premature failure.

Purpose of the Study:

• To investigate and compare the performance of a novel double-angle (DA) split-wedge anchorage system with a conventional single-angle (SA) configuration for pultruded carbon fiber-reinforced polymer (PCFRP) tendons.
• To evaluate the effectiveness of the DA anchorage in mitigating stress concentrations at the tendon's loading end.
• To utilize experimental data for calibrating nonlinear finite element models for further analysis.

Main Methods:

• Experimental tensile testing of 12 mm-diameter PCFRP tendon prototypes using both SA and DA wedge anchorage configurations.
• Performance evaluation based on achieved cable capacity and anchorage efficiency.
• Development and calibration of nonlinear finite element models using experimental results to simulate stress distribution and component behavior.

Main Results:

• The DA wedge configuration successfully achieved the average cable capacity (257 kN) in one test, demonstrating high efficiency.
• Numerical simulations confirmed that the DA configuration effectively avoids stress peak superpositions on the PCFRP tendon.
• The DA anchorage resulted in reduced pressure at the loading end of the tendon compared to the SA configuration.

Conclusions:

• The optimized DA split-wedge anchorage system is highly effective for PCFRP tendons in prestressing applications.
• The DA design significantly enhances anchorage performance by mitigating critical stress concentrations, thereby improving safety and reliability.
• Finite element analysis provides valuable insights into the behavior of anchorage components and validates the benefits of the DA configuration.