Cogon Fiber in Earth Brick as a Sustainable Building Material

Abstract The study on earth brick mixed with cogon fiber and cow dung as a sustainable building material was carried out by  an experimental method by field and laboratory set up. The study aims to technically analyze earth brick reinforced with cogon fiber and cow dung, determine favorable soil parameters, fiber length, fiber percentage, compare water absorption, CO2 emissions, and cost per unit brick with that of commercial burnt clay bricks. The scope of study covers the physical and mechanical properties of soil and earth brick, design mix proportion for cogon fiber-reinforced earth brick as an alternative to burnt clay bricks in rural areas.  The study area covers the locality of Phuntsholing and Tading Gewog. From the experimental tests, suitable soil findings are well graded sandy soil with a specific gravity of 2.69, MDD of 1.34g/cc, and OMC of 18.75%. In the case of earth brick fiber length of 30mm and fiber percentage of 4% resulted in maximum flexural and compressive strength. The average water absorption of cogon fiber-reinforced earth brick was 25.38% determined, indicating that this earth brick is suitable only in dry environment or otherwise a better stabilizer is required to limit the water absorption and the unit cost of earth brick at Tading gewog was 25% cheaper in comparison to 3nd class burnt clay bricks. The future study required are durability, provision of interlocking mechanism, and strength variation with arrangement of fibers in the earth brick.