COMBINED EFFECT OF BAMBOO FIBER AND KAOLIN ON CONCRETE PROPERTIES: AN EXPERIMENTAL STUDY

Abstract

Concrete is the most widely used construction material globally, but its production is energy-intensive, depletes natural resources, and contributes significantly to CO₂ emissions. This study investigates the potential of using locally sourced waste materials—calcined kaolin (CK) as a partial cement replacement and bamboo fiber (BF) as reinforcement—to develop a more sustainable concrete. An experimental program was conducted to evaluate the mechanical properties of concrete mixes with CK (4%, 8%, 12% by weight of cement) and BF (0.5%, 1%, 1.5% by volume of concrete). The compressive, splitting tensile, and flexural strengths were tested after 7, 14, and 28 days of curing. The results indicate that the combination of 8% CK and 1% BF (mix CK8BF1) yielded the optimal performance, with a 28-day compressive strength of 37.9 MPa, approximately 10.5% higher than that of the control concrete (34.3 MPa). Strength improvements were also observed in splitting tensile and flexural tests for this optimal mix. Beyond these optimum percentages, strength declined due to a reduction in cementitious content and the balling effect of fibers. This research demonstrates that the synergistic use of calcined kaolin and bamboo fiber can enhance mechanical properties while reducing the environmental footprint of concrete, offering a promising alternative for sustainable construction, particularly in regions where these materials are abundant.

Keywords: Concrete, calcined kaolin, metakaolin, bamboo fibers, mechanical properties, sustainable construction