Description
ABSTRACT
This work is on the experimental studies on the use of coconut fibre and banana fibre to enhance the strength and applications of concrete. These natural fibres have excellent physical and mechanical properties and can be utilized more effectively. They are economical (zero cost), with no chemicals. The addition of coconut-fibres and banana fibres significantly improved many of the engineering properties of the concrete notably compressive strength, tensile strength and flexural strength. The ability to resist cracking and spalling were also enhanced. Thus it acts as a natural admixture giving additional properties to the ordinary cement concrete. In this context six different percentages of coconut fibres and banana fibres (5%, 10%, 15%, 20%, 25% and 30%) having 40mm length were used. M20 concrete and Ordinary Portland cement of grade 43 was used. The coconut fibre and banana fibre reinforced concrete are tested for compressive strength, splitting tensile strength, flexural strength at different ages.
CHAPTER ONE
1.0 INTRODUCTION
1.1 Background of the study
The construction industry is revolutionizing in two major ways. One way is the development of construction techniques, such as using automated tools in construction. The other is the advancement in high-performance construction materials, such as the introduction of high strength concrete. Among these high- performance materials, fibre reinforced concrete (FRC) is gradually gaining acceptance from civil engineers. In recent years, research and development of fibres and matrix materials and fabrication process related to construction industry have grown rapidly. Their advantages over other construction materials are their high tensile strength to weight ratio, ability to be moulded into various shapes and potential resistance to environmental conditions, resulting in potentially low maintenance cost. These properties make FRC composite a good alternative for innovative construction. Their application in construction includes both upgrading existing structures and building new ones, which can apply to various types of structure, for example offshore platforms, buildings and bridges (Thou, 2005).
Even though the market for fibre reinforced concrete is still small compared to the overall production of concrete, the worldwide yearly consumption of fibres used in concrete is 300,000 tons. Concrete containing hydraulic cement, water, aggregate, and discontinuous discrete fibers is called fibre reinforced concrete. Fibres can be in form of coconut fibre, banana fibre, steel fibre, glass fibre, natural fibre , synthetic fibre, etc. The fibres are used to reduce shrinkage cracking. Main role of fibres is to bridge the cracks that develop in concrete and increase the ductility of concrete elements, improvement on post cracking behavior of concrete. It increase more resistance to Impact load, controls plastic shrinkage cracking and drying shrinkage cracking and lowers the permeability of concrete matrix and thus reduce the bleeding of water. The fibre enhances the toughness property of concrete. Toughness is the ability of a material to absorb energy and plastically deform without fracturing. It can also be defined as resistance to fracture of a material when stressed. Disperse fibres offer various advantages of steel bars and wire mesh to reduce shrinkage cracks. The fibres are less sensitive to corrosion than the reinforcing steel bars and the fibres can reduce the labor cost of placing the bars and wire mesh. Coconut and banana fibre reinforced concrete have been used for making roof tiles, corrugated sheets, pipes, silos and tanks. Concrete made with Portland cement has certain characteristics; it is strong in compression but weak in tension and tends to be brittle. The weakness in tension can be overcome by the use of conventional steel bar reinforcement and to some extent by the inclusion of a sufficient volume of certain fibres. The use of fibres also alters the behavior of the fibre – matrix composite after it has cracked, thereby improving its toughness. The objective of this research is to experiment on the use of coconut fibres and banana fibres as an enhancement of concrete.
1.2 Problem statement
Now a day’s infrastructure development across the world created demand for construction material. Concrete is the premier civil engineering construction material, concrete contains ingredients like cement, aggregates, water and admixtures. At present, huge quantities of constructions materials are required in developing countries due to continued infrastructural growth and also huge quantities of agricultural waste of banana crop are generated every in our country almost all 13.5 million tons per annual. The banana and coconut waste decomposition is a very serious problem for the farmers because one side it goes as agriculture waste and other side it pollutes environment. Banana and coconut forming generates more quantity of biomass which goes as waste. This waste material can help to increase the strength of concrete.
Before now, there are other types of fibre reinforced concrete such as concrete using steel fibres. The major challenge towards development of high performance concrete using steel fibres is the high costs involved, availability and also problem of corrosion. Coconut and banana fibre being the most ductile among all natural fibres (Majid Ali et al.,2012) has the potential to be used as a reinforcement material in concrete. It is biodegradable so the impact on environment will be minimal. This is also a way to dispose of the fibres which are derived as waste materials from coir based manufacturing units to produce high strength materials. They are also non-abrasive in nature, cheap and easily available.
1.3 Aim and Objectives of the study
The aim of this study is to experiment on the use of locally made fibre (coconut and banana fibres) as an enhancement of concrete.
The objectives of this work are:
- To find out variation in compressive, tensile and flexural strengths of using locally made fibre in reinforced cement
- To determine the influence of fibres on strength of concrete
- To generate a means of reducing agricultural waste thereby taking care of environmental pollution
1.4 Significance of the study
Coconut and banana fibre is the toughest among all natural fibres (Munawar et al., 2003). They are capable of taking strains4–6 times higher than other fibres (Munawar et al., 2003).Although they cheap and efficient a major hindrance towards its wide scale use is the high rate of water absorption, which can be reduced by coating it with oil.
The advantages of coconut and banana fibre are :low cost (they are gotten from agricultural waste), reasonable specific strength, low density, ease of availability, enhanced energy recovery, biodegradability, ability to be recycled in nature in a carbon neutral manner, resistance to fungi moth and rot, excellent insulation to sound, flame, moisture and dampness, toughness, durability, resilience.
This study will serve as a means of identifying the improvement in strength characteristics of concrete with the addition of oil coated coconut and banana fibre.
Natural resources used for the manufacture of concrete can be saved by using agri- cultural wastes because this waste is present in larger amounts and easily available. By adopting this technique, waste can be disposed of and at the same time, the environment can be saved from being polluted (Albajawi et al., 2021).
1.5 Scope of the study
The scope of this study covers developing locally made fibre reinforced concrete using coconut and banana fibres. In this study coconut and banana fibre is added to concrete and Plain Cement Concrete (PCC) is used as reference to study its effect on flexural, compressive and tensile strength properties and also drying shrinkage. Fibre is coated with oil so as to decrease the water absorption. Some of the advantages being observed are low-cost, low density, reasonable specific strength, good thermal insulation, reduced wear and ability to be recycled with minimal impact on environment (Majid Ali et al.,2011). Thus in addition to the enhancement in the physical properties of concrete, it turns out to be a sustainable waste management technique
1.6 Organization of Report
The complete work is presented in five chapters as follows:
In Chapter 2, review of literature related to natural fibres, Coconut fibre reinforced concrete, banana fibre reinforced concrete and influence of length of fibres on strength are discussed
In Chapter 3, a detailed explanation of the methodology used for this research work
Chapter 4 gives an overview of various materials used in the test and the material tests associated with them to determine its suitability in this research, interpretation of results, is a detailed outlay of different strength tests on specimens along with its justification.
Chapter 6 summarizes the study, presents the salient conclusions from the study and its limitations, and discusses scope for future.
