An Innovative Wedge Anchorage for CFRP Plates: Finite Element Modeling and Experimental Verification

The corrosion-resistant carbon fiber reinforced polymer (CFRP) has been proven to be a good candidate for repairing and strengthening concrete structures attributed of its lightweight and high tensile strength. Prestressing CFRP strengthening materials such as plates will have a high impact on improving the performance of the strengthened structures while utilizing the high strength of the CFRP. However, the process is hindered by the lack of a suitable anchorage system to grip the CFRP due to the sensitivity of the CFRP to the lateral gripping stress. The proposed mechanical wedge anchorage system for gripping CFRP plates was made of two soft copper sleeves, two steel wedges, and a steel barrel. Developing an accurate finite element (FE) model of the anchorage is crucial to thoroughly understand the stress distribution within the anchorage and the interactions between its components and the gripped CFRP plate. In this paper, a three-dimensional FE model was developed and verified. The symmetric model consisted of a CFRP plate, a copper sleeve, a steel wedge, and a steel barrel. Different experimentally verified contact conditions were applied at the CFRP-sleeve, sleeve-wedge, and wedge-barrel interfaces to accurately simulate the presetting and tensile loading processes of the wedge anchorage. The accuracy of the FEM model was illustrated by the notable agreement between its results and experimental results.