Role of treatment on enhancing the utilization of agricultural residues in cement-fiber brick

Recently, increasing global waste problem has awaken worldwide to more concern about environmental sustainability by encouraging of utilizing sustainable materials such as those from natural resources. In order to reduce the detrimental effect of synthetic materials on the environment, it has challenged engineer to investigate how it can be achieved by benefiting the agricultural residues into useful products. These included the use of by-products and waste materials in building construction. The use of these waste materials in construction will realize much benefit. In this research study, cement-fiber brick (CFB) are prepared from 10, 20 and 30% wt of rice husk (RH), corncob (CB) and coconut coir (CC) fiber. These fiber are mechanically and chemically treated in order to study effect of treatment on surface morphologies and Water Retention Value (WRV) of the natural fibers. Chemical treatment such as gelatin-hexamine (GH), linseed oil (LO) and sodium metasilicate-aluminium sulphate (AL-SM) was applied in this study. These treatments are used to modify the fibers prior to bricks fabrication in order to improve their dewatering behaviour (physical properties) and enhance the cement-fiber bonding (mechanical properties). Fiber/cement ratio of 1:9, 2:8 and 3:7 was used for CFB fabrication. Results showed that the properties of CFB were affected by type of fibers, treatments and fiber composition. Regardless of kind of treatments and fiber compositions, coconut coir brick (CCB) showed the greater water absorption (WA) which is 5.49% follow by rice husk brick (RHB) and corncob brick (CBB) which is 10.72% and 12.34% respectively. CCB also showed compression and flexural strength values greater than those obtained for other fibers. In case of type of treatments applied, fiber treated with LO produced bricks with better physical properties compared to others treatment. It was observed that fiber content also played an important role on influencing the mechanical properties of CFB. CFB with 20% wt fiber shows better compression and flexural strength regardless of treatment applied. CFB of LO treated fibers possess the higher properties, 4.7-8.8 MPa and 1.7-3.1 MPa for compression and flexural strength respectively. From the result obtained, it was found that CC has shown the most potential fiber and LO shows the best treatment that enhance the properties of the fabricated cement-brick. Thus, it proved that type of fibers, treatments and fiber composition has significant role in producing the high strength of bricks and meet the building criteria for construction. It is demonstrated that the concept of green composite bricks for sustainable infrastructure is feasible, although an extensive amount of research remains ahead.