Novel embedded steel wire GFRP-FBG smart rebar and its properties

In this paper, in order to improve properties of FRP rebar such as low elastic modulus, bad safety performance and so on, according to preparation principle of unidirectional hybrid fibers FRP rebar, we designed a novel embedded steel wire GFRP-FBG smartbar. The basic structure and production process have also been given in details. Then the novel smart rebar has been tested by serious experiments to research its mechanical and sensing properties. The monitoring results show that the elastic modulus of novel smart rebar is higher than one of the common GFRP rebar, and the elastic modulus of the rebar with two steel wires, three steel sires and four steel wires is increased by 3.1%, 5.8%, 8.0%. The strain sensing characteristics is fine, and the strain sensitivity coefficient agrees with the normal GFRP smart rebar. Linear correlation coefficient of strain sensing is 99.973%, and sensitivity coefficients of the rebar with embedded two steel wires, three steel wires and four steel wire respectively are 1.12 pm/με, 1.14 pm/με and 1.18 pm/με. Such kind of embedded steel wires GFRP-OF smart rebar can be used for both structural and functional materials in practical structure.