PROPERTIES OF CONCRETE WITH COCONUT HUSK AND DRIED BANANA LEAF FIBERS AS AGGREGATE REPLACEMENT INTRODUCTION RATIONALE Man has been using fiber to reinforce building materials for thousands of years – for example mud huts using straw in the mix. Asbestos reinforcing was phased out once its health risks became known. Today‟s fiber reinforced concrete („FRC‟) is a long way advanced on mud, though. Synthetic (and even natural) fibers may be added to the concrete mix, whether it is to be steel reinforced, or not. A wide range of fibers from fine steel fibers to glass and polypropylene are used today, and new fibers are being explored. The use of fibers is not always for structural strength purposes in the way that we think of traditional steel-reinforced concrete, although they do increase tensile and shear strengths. Modern fibers modify the properties of the concrete in predictable, measurable but more subtle ways for use in specialized construction applications. Fibers are usually used in concrete to control cracking due to plastic shrinkage and to drying shrinkage. They also reduce the permeability of concrete and thus reduce bleeding of water. Some types of fibers produce greater impact–, abrasion–, and shatter–resistance in concrete. Generally fibers do not increase the flexural strength of concrete, and so cannot replace moment–resisting or structural steel reinforcement. Indeed, some fibers actually reduce the strength of concrete.
Some recent research indicated that using fibers in concrete has limited effect on the impact resistance of the materials. This finding is very important since traditionally, people think
that ductility increases when concrete is reinforced with fibers. The results also indicated that the use of micro fibers offers better impact resistance to that of longer fibers.
Furthermore, with the increase of infrastructure development across the world, the demand for construction materials also increased, resulting to the raise in the necessity of concrete, which is a premier civil engineering construction material with aggregates forming on the major part. STATEMENT OF THE PROBLEM The study was conducted in response to the requirement for the Construction and Materials CE415 Lab project. This study aims to find materials that are recyclable and at the same time, a great aggregate replacement. Specifically the researchers seek to answer the following questions: 1.
Could Coconut Husk and Dried Banana Leaves improve the strength of the concrete
hollow block? 2.
If used as an aggregate replacement, could they sustain and improve solutions on solid
waste management? 3.
Could this be a good and economical material as an aggregate for concrete hollow
blocks? THEORETICAL BACKGROUND According to Cheryl Torrie, an eHow Contributor, Architects and structural engineers design buildings with concrete blocks (also known as concrete masonry units, or CMUs) for a
number of important properties: high structural capacity, resistance to fire, resistance to water, variety of aesthetic possibilities and insulating and acoustical advantages. As the researchers have found, according to D. Chandramohan & K. Marimuthu, Common fiber reinforced composites are composed of fibers and a matrix. Fibers are the reinforcement and the main source of strength while matrix glues all the fibers together in shape and transfers stresses between the reinforcing fibers. The fibers carry the loads along their longitudinal directions. Sometimes, filler might be added to smooth the manufacturing process, impact special properties to the composites, and / or reduce the product cost. Furthermore, Banana fiber, a ligno-cellulosic fiber, obtained from the pseudo-stem of banana plant (Musa sepientum), is a bast fiber with relatively good mechanical properties. The “”pseudo-stem‟‟ is a clustered, cylindrical aggregation of leaf stalk bases. Banana fiber at present is a waste product of banana cultivation and either not properly utilized or partially done so. The extraction of fiber from the pseudostem is not a common practice and much of the stem is not used for production of fibers. The buyers for banana fibers are erratic and there is no systematic way to extract the fibres regularly. Useful applications of such fibres would regularize the
demand
which
would
be
reflected
in
a
fall
of
the
prices.
Based from the textileschool.com on the topic of coconut fiber, coconut fibre belongs to the group of hard structural fibres. It is an important commercial product obtained from the husk of the coconut. Industries based on coir have developed in many coconut producing countries especially India, Tanzania, Kenya, Bangladesh, Burma, Thailand, Sri Lanka, Nigeria, Ghana etc.
Moreover, basing from the theories mentioned, the researchers wanted to solve the endeavor on using the fibers from the coconut husk and dried banana leaf as an aggregate replacement. SIGNIFICANCE OF THE STUDY The study will be a significant endeavor for the practical concept of building construction materials by the use of recyclable elements that can help in the development of future research studies on solid and agricultural waste management, solutions for economic advancement of the country, and reference material for students. HYPOTHESIS Based on the foregoing research problem, the researchers formulated the following null hypothesis:
The materials, Dried Banana Leaf and Coconut Husk, improved the strength and durability of the concrete hollow block as an aggregate.
The use of Dried Banana Leaf and Coconut Husk as an aggregate replacement lowers the compressive and tensile strength of the concrete hollow block and is recommended only as an aggregate additive.
SCOPE and LIMITATION
The researchers on the study of “Properties Of Concrete With Coconut Husk And Dried Banana Leaf Fibers As Aggregate Replacement” would discuss on the properties of concrete and the properties on the fibers of Coconut Husk and Dried Banana Leaf with a background on aggregates and reinforced concrete designing.
Specific topics that the researchers would explore will include the materials‟ chemical properties and its availability in the province of Bohol having Ubujan, Tagbilaran City and Brgy. San Roque Baclayon as the sources of location. Coconut, Banana Trees and composite junks along the road and households as the main source of the materials to be used. The study will range and finish for a span of 6 months starting from June to the end of October, references will come mainly from the web, from books on materials engineering and concrete design, and other research from previous students who have taken the same material for use on reinforced concrete design. The study will not exceed in discussing on the materials‟ other uses, its economic value, and methods of chemical extraction.
