Improving the flexural rigidity of laminated bamboo beams using fiber reinforcement polymer

Laminated bamboo presents potential physical and mechanical properties for being used as a construction material. However, this material presents low capacity if being used as a beam with a bending moment load due to its low flexural rigidity. The low flexural rigidity enlarges the beam deflection and lowers the service load, leading to the non-optimum usage of laminated bamboo with excellent strength. To increase the flexural rigidity in this study, laminated bamboo beams were given additional Carbon Fiber Reinforcement Polymer (CFRP) on the tension section, compression section, as well as the tension and compression section. The CFRP was also applied with various lengths of 0.2, 0.5, and 0.7 L, where L represents the beam span length. The results of the four-point bending test showed that the addition of CFRP to laminated bamboo beams significantly increases the flexural rigidity. The flexural rigidity level is directly proportional to the length of the CFRP used, according to the equation y = 0.608 x + 1.192, where y (multiplied by 1010) is the flexural rigidity of the beam and x is the ratio of the CFRP length toward the length of the beam span. The increase of flexural rigidity for the CFRP with length variations of 0.2, 0.5, and 0.7 L are 15.36, 24.90, and 38.86% calculated toward the control beam. Further, the placement of CFRP also increases flexural rigidity. The lowest increase in flexural rigidity occurred in beams given CFRP in compression was 24.25%, followed by beams treated with CFRP in tension of 28.79%, and the highest flexural rigidity was observed in beams that were given CFRP in tension and compression, of 38.86%, each calculated in comparison to the control beam.