PSI - Issue 70

Oberoi Kabrambam et al. / Procedia Structural Integrity 70 (2025) 74–81

79

5. Validation of FE model Validation of FE model is done using FE model of 4-point bend test of square and rectangle CFST beam against experimental data (SCS-IC3) and (RCS-IC2) respectively conducted by İlgün and Sancioğlu (2023) using same material properties. Moment vs mid-span displacement graph of FE model is compared with the corresponding experimental graph and is found to be matching very well as shown in Fig. 6. and Fig. 7.

Fig. 6. Validation of square FE model.

Fig. 7. Validation of rectangular FE model

Table 2. Validation results.

Specimen

M u,EXP (kNm)

M u,FE (kNm)

M u,FE /M u,EXP

SCS-IC3

12.78

13.1

1.02

RCS-IC2

13.95

14.53

1.04

6. FE model results and discussions After the validation is done, 4-point bend test of regular hexagonal CFST beam has been done numerically using ABAQUS software to know about its flexural strength. Moment vs mid-span displacement of hexagonal CFST beam has been shown in Fig. 8. The thickness of the stube tube used for the analysis is kept constant at t= 2.5 mm, which comes under class 4 section as per Eurocode 3 (Part 1-4). The results of the variation of ultimate moment along with the changes of concrete strength is shown in Fig. 9, it shows that the ultimate moment increases with increase in the strength of concrete. The ultimate strength increases by 6.33%, 6.84%, 5.78% for the increase in concrete strength from 20 to 25, 25 to 30, 30 to 35 MPa respectively.