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Bamboo Mesh Reinforced Cement Composites
INTRO...
• Bamboo is abundant in tropical and subtropical region• Able to be used for low-cost building material– Rural housing– Reinforcement for concrete
• Advantages : High STR, Low cost, Abundance• Disadvantages : low E, Poor bonding, Water
absorption– Poor bonding + Water absorption = No composite
action
Any Solution?
• Apply treatment for Bamboo– Make bamboo less water-absorbing– Make the interface between bamboo and cement
rougher• Coconut fiber (????)
• Increase casting pressure– Increased casting pressure ensures better matrix
impregnation
The Variables
• Bamboo culm Strips Woven MeshTreatedUn-treatedSize and layer number variedNormal casting pressureIncreased casting pressure
The Measured Results
• Tensile Strength– Failure behavior
• Flexural/Bending Strength– Failure behavior
• Impact Strength Charpy Impact Test– Notched???
THE EXPERIMENT
• Materials
• Preparation
• Experiment Procedure
• Results and Discussion
The Materials – Bamboo Mesh
• 3 Series of bamboo : A, B, and C– Local Bamboo, Seasoned for 2 months– Width = 5.5 mm; Thickness = 0.88 mm
• A : Not Treated• B : Treated• C : Treated– Increased casting pressure
The Materials - Mortar
• Portland Cement + Mortar, 1 : 1.5• Water/Mixture ratio = 0.4• Adimixture Rapidard 60cc/kg– Accelerate curing time
The Preparation
• Tensile Specimen : 304x50x19 mm – Width of specimen’s end = 76 mm
• Flexural Specimen : 375x100x19 mm• Impact Specimen : 70x45x19• Coating : Using water sealer by brushing, dry
in air 24 hours
• Bamboo Mesh
• Cast in plywood molds• Bamboo meshes tied by wire• The mortar pressed manually, then vibrate for
30 seconds• Specimen C Casting pressure applied using
jack• De-mold after 24 hours Water curing for
5 days (???) air drying for 24 hours
Test Procedure
• Tensile and Flexural Instron Testing Machine• Impact Charpy
Results and Discussion - Tensile
• Tensile behavior – Approximately linear until crack– After crack = Stress drop (influenced by bamboo
volume fraction)– Load increase after redistribution of internal force
occur (???)
• Failure mode = Destruction of bamboo – matrix bond
Result and Discussion - Flexural
• Similar to tensile• Difference : Multiple cracks instead of single
crack
Overall Test Results
Conclusion
• Bamboo mesh adds considerable ductility and toughness to the mortar
• Failure mode is interface breaking Still low on interface strength
• Applying pressure may increase composite action between bamboo and matrix
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