Carbon Fibers in Civil Structures: Rehabilitation and New Construction

label Proiecte autorenew 2025-09-29, 16:59 history_edu irina lungu
Fibre reinforced polymers (FRP’s) have light weight, excellent durability, and high strength – the latter particularly when the fibres are oriented unidirectionally within the composite. These properties make these materials attractive for use in strengthening and rehabilitation of structures.

In Canada, FRP’s have been used in various applications in both new construction and rehabilitation. We describe those research projects associated with masonry – post-tensioning with Carbon FRP tendons to provide improved serviceability and reduce crack sizes in damaged structures: wrapping damaged columns with CFRP sheets to restore/increase strength: and lastly using Glass FRP sheets to increase the flexural capacity and energy absorption characteristics of plain and reinforced concrete blockwork. The former two projects were performed at Calgary and the latter at the University of Alberta, Edmonton. All projects show considerable promise for their respective applications. FRP’s therefore will provide an additional option for structural engineers when considering these types of.

STRENGTHENING WITH COMPOSITES

Background
In the case of reinforced (RC) or prestressed concrete (PC) structures, a promising new repair technology involves the use of externally bonded FRP laminates. Similar to steel plate bonding, FRP laminate bonding involves adhering a thin, flexible fiber sheet to the concrete surface with a thermoset resin. This technique, known as manual lay-up, may be used to increase the shear and flexural capacity of beams and slabs and to increase confinement in columns. In addition, the system does not add significant dead load to the structure, suffers little from corrosion, and may be installed in a relatively short period of time. Figure 1 shows (a) the fiber sheet and (b) its installation.