Xinmiao Meng_The mechanical properties of cracked round bamboo reinforced with FRP sheets subjected to axial compression
1. The mechanical properties of cracked round bamboo
reinforced with FRP sheets subjected to axial compression
Xinmiao MENG Lecturer
Department of Civil Engineering, Beijing Forestry University, Beijing, China
Peng FENG Professor
Department of Civil Engineering, Tsinghua University, Beijing, China
Youde WU M.S. student (THU)
Qiang DENG M.S. student (BFU)
7. Experimental research
Specimens
• Cut from a single round pole bamboo
• Each specimen about 200 mm in height
• Divided into four groups
• Two reinforcements: full wrapped and half wrapped
• GFRP: HITEX-G430S ( unidirectional fabric, 430 g/m2 ),
epoxy resin, hand lay-up
Details of specimens
Specimens Location
Height
(cm)
Crack
Reinforce
-ment
A1-B-20-U Bottom 20 Uncrack /
A2-M-20-U Middle 20 Uncrack /
A3-T-20-U Top 20 Uncrack /
B1-B-20-C Bottom 20 Severe crack /
B2-M-20-C Middle 20 Slight crack /
B3-T-20-C Top 20 Slight crack /
C1-B-20-F Bottom 20 Severe crack Full
C2-M-20-F Middle 20 Slight crack Full
C3-T-20-F Top 20 Slight crack Full
D1-B-20-H Bottom 20 Severe crack Half
D2-M-20-H Middle 20 Slight crack Half
D3-T-20-H Top 20 Slight crack Half
12. 3. Results and discussion
Compressive strength
Group
Strength
(MPa)
Increase
A 57.20 1.25
B 45.76 1
C 57.82 1.26
D 55.69 1.22
Full wrapped
Half wrapped
13. 3. Results and discussion
Ductility
Full wrapped
Half wrapped
• Cracks decreased the ductility
• FRP reinforcement increased
the ductility
14. 3. Results and discussion
Failure modes
• Full wrapped
prevented the
outward split
• Inward deformation
couldn’t avoid
A1-A3 B1-B3 C1-C3 D1-D3
15. 3. Results and discussion
Confinement effect
• The transverse strains were
much little than the ultimate
strain. (5000 me << 15000 me)
• The confinement effect wasn’t
fully used.
Strain (me)
Load(kN)
C1
17. 4. Conclusion
• The wrapping method changed the failure modes from
outward split to inward deformation, and improved the peak
loads and markedly improved compression deformation.
• The confinement effect of FRP sheets wasn’t fully used.
• The reinforced cracked round pole bamboos showed better
mechanical behavior, which might promote the development
and application bamboos in constructions and buildings.