Chapter 7. Conclusions and Suggestions for Future Work
7.2 Suggestions for future work
The results from this research highlighted a number of topics which need additional exploration and investigation. The final section identified potential areas for further work.
The experimental and numerical studies in this research focused on investigating the inelastic behaviour of PEC members and CFT members. Particular attention was given to PEC members due to the increased application in worldwide practice. In order to enhance the ductility of PEC members, two transverse link alternatives were examined. Since the behaviour was mainly determined by the plastic hinge zone, the findings were able to be used in other similar members with different geometry and boundary conditions. In addition, there is still a need to validate the application of new transverse links in other type of composite members. Furthermore, the research here reported concentrated on the behaviour of PEC members subjected to cyclic loads along their major axis. It is necessary to study the behaviour of PEC members under the similar cyclic loads in the minor axial direction.
Finite element program ABAQUS/Dynamic was used to simulate the hysteretic performance of PEC and CFT members. The application of this method could be extended to other structural element or other cyclic loading programs. The detailed three-dimensional analysis provided useful insight into the local buckling behaviour and forces developing in additional links. The results involve complex interactions
107
that would provide useful information for the future work. On the other hand, the fracture of the steel profile could not be simulated in the analysis here, and appears to be an important issue for future study.
This thesis provided information on the response of composite members under cyclic loads. Methods for estimating the inelastic demands on critical members were based on the limited loading condition. It is necessary to expand the research to the fields of various extreme loading conditions, such as impact, blast or seismic scenarios.
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Appendix A Supplementary Experimental Results
for PEC members
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
Figure A. 1 Strain-Displacement response for IC1 (Cont’d)
115
Figure A. 1 Strain-Displacement response for IC1
-1.5 -1.0 -0.5 0.0 0.5 1.0
Displacement (mm)
Strain (%) G24
Figure A. 2 Strain-Displacement response for IC2 (Cont’d)
117
Figure A. 2 Strain-Displacement response for IC2
-1.0 -0.5 0.0 0.5 1.0 1.5
Figure A. 3 Strain-Displacement response for IC3 (Cont’d)
119
Figure A. 3 Strain-Displacement response for IC3
-3.5 -3.0 -2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5
Figure A. 4 Strain-Displacement response for IC4 (Cont’d)
121
Figure A. 4 Strain-Displacement response for IC4
-1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 2.5
Figure A. 5 Strain-Displacement response for IC5 (Cont’d)
123
Figure A. 5 Strain-Displacement response for IC5
-4.0 -3.5 -3.0 -2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0
Figure A. 6 Strain-Displacement response for IC6 (Cont’d)
125
Figure A. 6 Strain-Displacement response for IC6
-2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0
Figure A. 7 Strain-Displacement response for IC7 (Cont’d)
127
Figure A. 7 Strain-Displacement response for IC7
Appendix B Supplementary Experimental Results
for CFT members
129
Figure B. 1 Strain-Displacement response for SY0 (Cont’d)
-5 -4 -3 -2 -1 0 1 -150
-100 -50 0 50 100 150
Displacement (mm)
Strain (%) G27
-10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 -150
-100 -50 0 50 100 150
Displacement (mm)
Strain (%) G28
Figure B. 1 Strain-Displacement response for SY0
131
Figure B. 2 Strain-Displacement response for SY1 (Cont’d)
-5 -4 -3 -2 -1 0 1 2 -150
-100 -50 0 50 100 150
Displacement (mm)
Strain (%) G27
-8 -6 -4 -2 0 2 4
-150 -100 -50 0 50 100 150
Displacement (mm)
Strain (%) G28
Figure B. 2 Strain-Displacement response for SY1
133
Displacement (mm)
Strain (%)
Displacement (mm)
Strain (%)
Displacement (mm)
Strain (%)
Displacement (mm)
Strain (%)
Displacement (mm)
Strain (%)
Displacement (mm)
Strain (%) G24
Figure B. 3 Strain-Displacement response for SY2 (Cont’d)
-0.5 0.0 0.5 1.0 1.5 2.0 2.5
Displacement (mm)
Strain (%)
Displacement (mm)
Strain (%)
Displacement (mm)
Strain (%)
Displacement (mm)
Strain (%) G28
Figure B. 3 Strain-Displacement response for SY2