## 4 Reference Beams  
To assess the calculation procedure explained in the previous section, experimental data related with RC flanged beams under pure torsion were searched in the literature [39]. As referred in the introduction section, few experimental studies were found in the literature for which full data were given. Some studies do not give all the properties of the beams (mechanical and geometrical) that are needed to calculate the \(M_{T}-\theta\) curve using the GSVATM. For instance, the full detailing of the reinforcement, the concrete cover or the full mechanical properties of the materials are not given. Other studies do not present the full experimental \(M_{T}-\theta\) curve, which is needed to compare with the theoretical one from the GSVATM. Finally, some studies include beams with atypical detailing for the reinforcement (for instance, flanges with insufficient or without transverse reinforcement) which led to atypical failure of the beams. All these reported cases were disregarded for the present study.  
As a result, only three RC L-shaped beams and one RC T-shaped beam were found and for which all the data are given. The beams are as follows: beam LB1 (L-shaped) and beam TB1 (T-shaped) from [PERSON] et al. in 2013 and 2014 [10; 40]; beams BL1 (L-shaped) from [PERSON] et al. in 2013 [41]; and beam BK-T (L-shaped) from [PERSON] and [PERSON] in 2011 [30].  
Due to the aforementioned, the literature review was expanded in order to incorporate additional reference flanged beams. Some recent studies were found which deal with flanged beams under pure torsion partially or fully reinforced with GFRP bars. From those studies, some beams (for which all data were given) were also incorporated in this study as reference beams. These are as follows ones: beams LB2, LB3, LB4 and LB5 (L-shaped) from [PERSON] et al. in 2014 [10].  
Tables 3-5 summarize the properties of the chosen reference beams. Figure 6 defines the geometrical parameters for the T- and L-shaped cross sections presented in Table 3.  
In Table 5, the meaning of the parameters are: \(f_{c}\) is the strength of concrete in compression; \(f_{\mathit{cf}}\) is the strength of concrete in tension; \(f_{\mathit{lf}}\) and \(f_{\mathit{lf}}\) are, respectively, the stresses corresponding to the yielding of the longitudinal and transverse steel reinforcement; \(f_{\mathit{lf}}\) and \(f_{\mathit{lf}}\) are, respectively, the stresses corresponding to the failure of the longitudinal and transverse GFRP reinforcement; \(E_{c}\) is [PERSON]'s modulus of concrete; \(E_{\mathit{sl}}\) and \(E_{\mathit{st}}\) are, respectively, [PERSON]'s modulus for the longitudinal and transverse steel reinforcement; \(E_{\mathit{lf}}\) and \(E_{\mathit{ft}}\) are, respectively, [PERSON]'s modulus for the longitudinal and transverse GFRP reinforcement; \(\varepsilon_{\mathit{oi}}\) and \(\varepsilon_{\mathit{cu}}\) are, respectively, the strain corresponding to the peak stress and the conventional ultimate strain for the concrete in compression; \(\varepsilon_{\mathit{slu}}\) and \(\varepsilon_{\mathit{stu}}\) are, respectively, the conventional ultimate strains for the longitudinal and transverse steel reinforcement; \(\varepsilon_{\mathit{flu}}\) and \(\varepsilon_{\mathit{fu}}\) are, respectively, the conventional ultimate strains for the longitudinal and transverse GFRP reinforcement.