Qualification of an epoxy resin system for use in secondarily formable CFRP rebars

Research output: Contribution to book/Conference proceedings/Anthology/ReportConference contributionContributedpeer-review

Abstract

The use of reinforcing bars has been known for more than 150 years in construction sector, in order to compensate the limited tensile strength of concrete. Steel is the most widespread and standardized rebar material. As industry targets a reduction of resource consumption and increased freedom of design, novel materials come into the scope of current research efforts. In this context, carbon fiber reinforced polymers (CFRP) have become a promising candidate for rebar materials as they offer excellent corrosion resistance and mechanical properties. Their use enables significant reduction of concrete cover in future buildings and cost-efficient maintenance of bridges. The resin system used for manufacturing of CFRP rebars dictates possible applications. Thermoplastic polymers offer the advantage of formability in a molten state. On the other hand, they provide limited heat and fire resistance, what hinders further industrialization. In contrast, thermosets deliver high mechanical and thermal properties due to their polymeric network structure. This is also the reason for their restricted formability after gelation has occurred. However, it is known that epoxy resins may sustain substantial plastic deformation when being deformed at elevated temperatures and in a partial cure state. In this work, a commercially available resin system is selected and qualified for potential use in thermoset-based CFRP rebars. Based on the resin characterization comprising reaction kinetics as well as tensile and compressive tests at partial cure, general guidelines and limits for secondary forming are derived. The feasibility is demonstrated by bending tests on CFRP stripes with varied fiber orientation.

Details

Original languageEnglish
Title of host publicationProceedings ESAFORM 2021
Place of PublicationLiège, Belgique
ISBN (electronic)9782870193020
Publication statusPublished - 1 Apr 2021
Peer-reviewedYes

Conference

Title24th International ESAFORM Conference on Material Forming
Abbreviated titleESAFORM 2021
Conference number24
Duration14 - 16 April 2021
Website
Degree of recognitionInternational event
Locationonline
CityLiège
CountryBelgium

External IDs

Scopus 85119370815
ORCID /0000-0003-1370-064X/work/142243425
ORCID /0000-0003-3624-3242/work/142255793

Keywords

Keywords

  • Fiber Reinforced Rebars, Plasticity, Thermoset