THE POTENTIAL OF BEMBAN FIBER AS RAW MATERIAL OF GEOPOLYMER

Abstract

This study focuses on modifying Bemban fiber (Donax Canniformis) and assessing its physical and mechanical properties as a material for concrete geopolymers. Bemban was cleaned and chopped into 20 cm pieces before being boiled for 60 minutes and dried at 75°C for 4 hours. Furthermore, the fiber was alkalized for 2 hours in a 3% NaOH solution. Three main aspects were investigated, such as water content, cellulose content, and the tensile strength of Bemban fiber. Moreover, the water absorption, porosity and compressive strength of mortar geopolymer using modified Bemban fiber were conducted in this research. The resulting research showed that the water content value of the Bemban fiber was 4% and met the requirements by SNI 06-3730-1995. Moreover, alkalization increased the cellulose content by 44.58% while decreasing the lignin content by 49.18% as well as shrinking the Bemban fiber diameter by 42%. The tensile strength of the Bemban fiber increases by 84.59%, and the fiber shape changes significantly. Carbon (C) and oxygen (O) are the most abundant elements in Bemban fiber. Using modified Bemban fiber in mortar geopolymers can reduce water absorption and porosity, especially the decrease in water absorption and porosity, together with the increased usage of Bemban fiber. Adding 1.5% modified Bemban fiber results in the lowest water absorption capacity and porosity, with physical parameters of 7.18% water absorption, 15.09% porosity, and the highest value of compressive strength is 5.93 MPa.