MECHANICAL PROPERTIES AND MORPHOLOGICAL STRUCTURES OF ALKALINE TREATED BAMBOO AND COCONUT FIBERS FOR NATURAL GEOTEXTILE APPLICATION

Abstract

Synthetic geotextiles are known for their wide range of applications in geotechnical engineering, especially for erosion control and slope stability. However, these materials are environmentally concerning due to their lack of biodegradability and are made of petroleum-based polymers. Hence, these materials can create environmental problems and have long-term ecological impacts. The objective is to (1) explore the mechanical properties and morphological properties of indigenous natural fibers (bamboo, coconut) and (2) to determine whether blended bamboo-coconut (BAMCO) fibers can replace synthetic fibers. The fibers were soaked in a 6% sodium hydroxide (NaOH) solution for 24 hours. Tensile strength of single fibers and twines and ropes was assessed using ASTM D3822 and ASTM D2256, respectively. Surface morphology was characterized by scanning electron microscopy (SEM), and cellulose content was quantified by Fourier transform infrared spectroscopy (FTIR), which explains the change in tensile strength. In the experimental results, the tensile strength of untreated bamboo fibers was higher (12.4375 MPa) than that of coconut fibers (1.84457 MPa). The tested properties indicate that tensile strength is enhanced by alkaline treatment in bamboo and coconut fibers, with values of 26.9175 MPa and 2.03689 MPa, respectively. This increased tensile strength is attributed to greater exposure of cellulose and the thicker fiber morphology. Furthermore, the load-carrying capacity also improved in composite bamboo-coconut or BAMCO rope made of the combined twines of single fibers. This study showed that natural fibers from bamboo and coconut, particularly the BAMCO geotextile, can be potential natural geotextiles.