American Journal of Construction and Building Materials 2020; 4(1): 22-26 http://www.sciencepublishinggroup.com/j/ajcbm doi: 10.11648/j.ajcbm.20200401.14 ISSN: 2640-0022 (Print); ISSN: 2640-0057 (Online) The Mechanical Properties of Fly Ash Concrete Reinforced with Bamboo Fibers Henock Eshetu Aweke 1 , Tesfaye Alemu Mohammed 2 1 Department of Civil Engineering, (Construction Technology and Management), Addis Ababa Science and Technology University, Addis Ababa, Ethiopia 2 Department of Civil Engineering, (Structural Engineering), Addis Ababa Science and Technology University, Addis Ababa, Ethiopia Email address: To cite this article: Henock Eshetu Aweke, Tesfaye Alemu Mohammed. The Mechanical Properties of Fly Ash Concrete Reinforced with Bamboo Fibers. American Journal of Construction and Building Materials. Vol. 4, No. 1, 2020, pp. 22-26. doi: 10.11648/j.ajcbm.20200401.14 Received: March 22, 2020; Accepted: April 3, 2020; Published: May 15, 2020 Abstract: In addition to the economic advantages, using fly ash in cement has enormous effect on the mechanical properties of the concrete. Moreover, Researchers have identified that the addition of fibers to concrete increases its mechanical properties. Therefore, Better concrete product using both fly ash and fibers especially natural fibers which are more economical and eco-friendlier than the other fibers for an improved concrete strength production is the major aim of this research. This experimental investigation had been undertaken to study a fly ash concrete reinforced with bamboo fibers. The optimum percentage of fly ash to replace cement was first determined by compressive strength test for different percentages by weight of fly ash substitution. After that, mechanical properties of the fly ash concrete were studied with the addition of three different percentages of bamboo fibers. Mix designs were formulated for all percentage and then, Specimens were casted and tested for computing compressive strengths, indirect tensile strengths and flexural strengths for 7 th and 28 th day period. In the experiments, non-fibrous 25% fly ash substituted with cement concrete (the optimum percentage which was first determined using compressive strength) were compared with the 25% flyash substituted with cement for the individual fibers percentages. The standard 150mm cube compressive strength of bamboo fiber reinforced Fly Ash Concrete (BFRFAC) with 0.10% addition of bamboo fiber by weight of concrete showed an increment of 12.44%, Whereas bamboo fiber reinforced Fly Ash Concrete with 0.2% and 0.30% addition of bamboo fiber by weight of concrete showed a compressive strength reduction of 9.33% and 33.03% respectively compared to non-fibrous fly ash concrete. Bamboo fiber reinforced Fly Ash Concrete with 0.10% and 0.20% bamboo fiber addition by weight of concrete showed an increment in mean split tensile strength of 5.81% and 0.12% respectively; whereas 0.30% additions of bamboo fiber by weight of concrete showed split tensile strength reduction of 14.54% compared to non-fibrous fly ash concrete. Mean Flexural strength of bamboo fiber reinforced Fly Ash Concrete with 0.10%, 0.20% and 0.30% addition of bamboo fiber by weight of concrete showed an increment by 2.48%, 5.98% and 7.80% compared to non-fibrous fly ash concrete respectively. Keywords: Fly Ash, Bamboo Fiber, Compressive Strength, Split Tensile Strength, Flexural Strength 1. Introduction Concrete is world most used construction material with its main ingredient, cement, with its fabrication accounts for 5 to 10% of the global carbon emission. This has driven scientists to create innovative alternatives with smaller carbon footprints. Therefore, scientists and researchers are studying additions and material replacements to raise the concrete’s performance to reduce its consumption, thus lowering the overall environmental impact. Industrial and agricultural waste by-products such as fly ashes ground granulated slag and rice husk ashes are used as supplementary cementitious materials in concrete. The incorporation of supplementary cementitious materials not only improves the mechanical properties of concrete but also reduces the cement consumption by replacing part of cement with these materials [1]. Over the last decades intensive research and development works has been taking place in the field of fiber reinforced concrete. In developing countries, the idea of using fibers to improve strength and ductility of the