International Journal of Civil and Structural Engineering Research ISSN 2348-7607 (Online) Vol. 7, Issue 1, pp: (146-154), Month: April 2019 - September 2019, Available at: www.researchpublish.com
Geo-polymer Modified Cellulosic Fibre Reinforced Concrete 1 1,2
Mohammad A. ALhashemi, 2Mazyad N. ALfadhli
(Public Authority for Applied Education and Training) (PAAET), KUWAIT.
Abstract: Normal concrete is characterised by high compressive strength but low tensile strength and with little elasticity causing it to fracture and crack due to its brittle nature. Reinforced concrete was discovered in a quest to produce a material with improved compressive and tensile strengths but it is faced with a disadvantage of long post crack formations due to strain softening. Normal reinforced concrete is faced by durability challenges due to ingression of deleterious substances such as chloride and carbonation ion attacks that result in corrosion of steel leading to complete structural deterioration. Concrete as a material is also itself susceptible to attack from the aggressive environment. The need for discovering sustainable and energy efficient construction materials have pushed researchers and academics to search for better and effective construction materials. Concrete is the most used construction material worldwide due to its outstanding properties, these include its versatility, durability and reliability in terms of availability of materials required in its production. Ordinary Portland cement is a crucial element required in concrete production. According to studies done by scientists, cement-producing industries are the second contributors to the rise in greenhouse gases. On the other hand, steel production is an expensive process requiring high consumption of energy and it generated from non-renewable mined ores. This study aims to produce a geo-polymer modified natural fibres reinforced concrete with improved resistance to impact loads, higher durability and low porosity. Fly ash is proposed to partially replace cement to form the geo-polymer modified concrete. Natural fibres made from sisal will be added in reasonable proportions based on past research to the geo-polymer modified concrete. To determine the strength and durability of the produced concrete compressive strength, tensile strength, flexural strength and chloride permeability tests will be performed to achieve the set objectives. Keywords: geo-polymer, Reinforced concrete, natural fibres, tensile strength, flexural strength.
1. INTRODUCTION Background Study Engineers and academics with goals to come up with sustainable and energy efficient building materials have done broad research in the past. Low construction costs have been achieved through structural design optimisation and application of sustainable construction. Geopolymer concrete and fibre reinforced concrete are some of the construction materials that have gained attention from researchers due to their many advantages. Industries manufacturing ordinary Portland cement (OPC) are responsible for 0.8 to 1 tonnes of Carbon IV Oxide release to the atmosphere for every 1 tonne of cement manufactured. This is equivalent to 5-10% global Carbon IV Oxide release. Calcining of Calcium Carbonate in the production of OPC is the major source of Carbon IV Oxide. Replacement of OPC with geo-polymer binder can reduce Carbon IV Oxide emissions for each cubic meter of OPC concrete replaced by 90%. Advantages of using geo-polymer cement include inherent protection of steel reinforcement due to low chloride diffusion and high residual pH, low thermal conductivity and low shrinkage, resistance to alkali-aggregate reactions, high resistance level to different salts and acids and improved fire resistance. These properties result in improved strength and concrete durability. Performance of geo-polymer concrete under impact loads can be improved by incorporation of fibre reinforcements into the concrete. With the rapidly increasing need for superior structural properties in concrete, cement concretes containing randomly distributed steel fibres is gaining importance. These composite structural materials portray durability, high energy
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