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