Title: Strength of Carbon Fiber-Reinforced Polymer (CFRP) Sheets Bonded to Concrete with CFRP Spike Anchors

Author(s): Alaa T. Al-Sammari and Sergio F. Breña

Publication: Structural Journal

Volume: 118

Issue: 1

Appears on pages(s): 153-166

Keywords: carbon fiber anchors (spike anchors); carbon fiber-reinforced polymer (CFRP) anchor fan; CFRP-concrete joints; CFRP debonding; CFRP finite element modeling; CFRP sheets; fiber-reinforced sheet anchorage; strengthening of concrete structures

DOI: 10.14359/51728084

Date: 1/1/2021

Abstract:
Carbon fiber-reinforced polymer (CFRP) materials in the form of CFRP sheets are widely used to rehabilitate existing concrete structures suffering deterioration. The high tensile strength, light weight, and durability of CFRP material make it a better alternative to steel and other strengthening materials. CFRP sheets are externally bonded to concrete elements to enhance strength and ductility. However, CFRP sheets may debond before reaching the ultimate strength of the CFRP material. This behavior reduces the strengthening efficiency of using CFRP sheets, and therefore, integrated CFRP composite anchors are added to the strengthening system to delay debonding. Yet, the effect of using these anchors is not quantified for design purposes. This research paper presents a new approach that is based on both finite element simulations and previous experimental tests to quantify the additional strength attained due to the use of CFRP anchors. The quantified strength is based on examining several parameters of the anchorage system, including the number of anchors used in the sheet; the distance between anchors, anchor shaft diameter, anchor fan diameter; and CFRP sheet thickness.