## 3 Results and Discussion
### Static Bending  
The static bending of the laminated woven bamboo mat boards is shown in Figure 6. Five-ply laminated boards have the highest MOE value of 10,885 MPa, while 7-ply has 10,705 MP and the lowest MOE value of 10,103 MPa was observed in 9-ply boards. Nine-ply boards have significantly lower MOE compared to that of 5-ply boards. As for MOR, the trend is in reverse order, where the highest MOR values were found in 9-ply boards (39.62 MPa), followed by 7-ply (34.42 MPa) and 5-ply (33.20 MPa). However, no significant difference between these boards in terms of MOR was observed.  
Figure 7 illustrates the failure modes of the sample after the static bending test was conducted while Figure 8 shows the micrograph of the failure samples. When observed under the SEM, the deformation and breakage of the fiber can be clearly seen in Figure 8.  
Figure 5: Density profile of 9-ply laminated woven bamboo mat boards (\(n=5\)).  
Figure 6: Modulus of rupture (MOR) and modulus of elasticity (MOE) of laminated woven bamboo mat boards of different py. Note: Mean follow by the same letters a, b is not significantly different at \(p\leq 0.05\).  
When compared to the other ply, the 9-ply structure showed the most deformation. The failure of bamboo fiber to support the load transferred between the resin and woven bamboo layer is most likely the cause of this, which also relates to the low interfacial bonding between the bamboo as the number of ply increases [21]. The interfacial debonding causes large cracks and holes in the 9-ply sample when compared to the 5- and 7-ply samples. Further stress load propagation causes an increase in the crack area, resulting in deformation of the bamboo fiber.  
Figure 8: Static bending test sample of (**a**) 5-ply, (**b**) 7-ply and (**c**) 9-ply under \(10\times\) magnification of Scanning Electron Microscope (SEM).  
Figure 7: Static bending test sample of (**a**) 5-ply, (**b**) 7-ply and (**c**) 9-ply.  
The static bending test was conducted on all three ply to know the sample's MOE and MOR value. MOE is used to determine the value of wood stiffness. It measures the resistance of the composite to bending deformation. Based on Figure 6 above, the 5-ply laminated woven bamboo has the highest value of MOE (10,886 \(\pm\) 838.44 MPa) compared to other numbers of ply, which correlates to the density of the composite, where 5-ply has the highest density. The MOE value showed a descending pattern as the number of ply increased.  
The MOR is also called flexural strength, which is related to both tensile and compressive strength, which varies with the inter-laminar shear strength [25]. The MOR value showed a contrasting value pattern when compared to MOE, where 9-ply woven bamboo has the highest MOR value (39.62 \(\pm\) 16.13 MPa). MOR value went ascending as the number of ply increases, whereas 5-ply woven bamboo with the lowest MOR value (33.20 \(\pm\) 17.74 MPa) showed lower flexural strength than 7- and 9-ply. Nine-ply woven bamboo shows better flexural properties compared to other ply due to the increase of interlacing fiber. The increasing number of ply and arrangement of the fiber causes the movement of the woven bamboo to be constrained, so the pressure and stress applied during the MOR test lead to an even distribution of force, indirectly enhancing the woven bamboo withstand threshold [21]. Furthermore, an increase in the ply number is related to an increase in bamboo fiber, thus, a stiffer end-result with less elastic qualities when enforced with pressure.