Reinforced Hollow Block (Chapter I to II)

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CHAPTER I
INTRODUCTION
This chapter presents the background of the study, statement of the problem, significance
of the study and its scope and limitations.
Background of the Study
Concern for sustainable development has emerged as one of the major societal issues of
the late 20th century. As to the increase in the worlds’ population and the urbanization of the world
leads to the major problem in housing and infrastructure. The durability of a building is determined
by the properties of the various components of the building in which concrete hollow block is
major. The utmost case that occur with concrete foundations result from a lack of maintenance.
An example of which is in, Omapariola (2014) Idiroko Area of Nigeria. There are several reported
cases of building collapse in Nigeria and one of the major causes is the lack of maintenance and
using of poor quality materials.
As a tropical country, Philippines are one of the world’s largest producers of coconut
products such as coconut oil, copra (dried coconut) and desiccated coconut. Historically, Southern
Tagalog, Bicol regions of Luzon and Eastern Visayas were the centers of coconut production of
land with coconut trees and its population was at least partly dependent on it for their livelihood
yet, a large amount of agricultural waste was disposed of. Poor management of disposing of may
lead to a social economic problem. Concrete hollow block is a very durable construction material.
And yet many concretes from last centuries bridges, highways, and buildings are crumbling many
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structures built this century will be obsolete before its end. In developing country like Philippines
hollow block are one of the most extensive used walling material in the Philippines. Concrete
hollow block is very weak against lateral loads. Hence, mostly the quality is poor (Global Shelter,
2014).
In 2013, the strong typhoon Yolanda struck Philippines especially in the region of Visayas.
The typhoon brought wide damages in Cebu. Recycling the disposed material is one method of
threating material the agricultural waste caused by the typhoon. The used of coconut shell and
waste glass could be a valuable substitute in the formation of composite material that can be used
as a housing construction, such as concrete hollow block. The researchers found a way of making
hollow blocks made up of recycled debris from the damaged agricultural wasted caused by the
typhoon.
Statement of the Problem
This study aimed to utilize waste products like broken glass and coconut shells as additives
in making a reinforced hollow block. Specifically, this study sought to address the following
objectives:
1. To come up with the desired ratio of the mixture of broken glass and coconut shells
that forms the desired reinforced hollow blocks:
1.1 Setup A;
1.2 Setup B;
1.3 Setup C; and
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1.4 Controlled Setup (Commercial).
2. To determine the absorptive capacity of the blocks as measured through the mass of
the hollow blocks after soaked in water for:
2.1 15 minutes;
2.2 30 minutes; and
2.3 45 minutes.
3. To test the significant difference of using Coconut (Cocus nucifera) Shell and Broken
Glass as Reinforced Hollow Block Additives.
Statement of the Hypothesis
H0
:
There is no significant difference of using Coconut (Cocus nucifera) Shell
and Broken Glass as Reinforced Hollow Block Additives.
Significance of the Study
This study can benefit the following individuals:
First, Low Income Earners. They can benefit from the project because using Reinforced
Hollow Blocks helps in saving construction materials and therefore, use of hollow blocks reduce
construction cost. Reinforced Hollow Blocks can safely withstand the atmosphere action and it
requires no protective covering;
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Second, Contractor and Home Builders. They will be provided with knowledge and
information to improve the method of construction using other materials as fine aggregate to
concrete hollow blocks;
Third, Government and Non-Government Sectors. They are given new ideas of
maximizing their resources on construction projects. This study will also make them
knowledgeable that junked materials can be used as construction materials and urge them to
finance further studies for the development of this study.
Lastly, the Future Researchers. Of other fields could be provided with a reference and can
give them knowledge about waste glass and coconut shells as an alternative aggregate for concrete
hollow block. This study will encourage them to study other materials that can be used as a
construction material and awaken their minds regarding environmental protection.
Scope and Limitation
This study deals mainly with the different problems commonly having bowed walls, shifted
and/or broken blocks. The researchers focus on making a solution for solving the problems of
concrete blocks in the Philippines as the subject of the study. Furthermore, the researchers chose
to solve this problem by making a Reinforced Hollow Blocks using coconut shells and waste glass
as additives. The study may be able to work but there are certain limitations. Such limitations
include the financial constraints, weather conditions affecting the curing time of the hollow block
and lack of equipment that accurately measures the durability of the hollow blocks. Since the
study has limited funds, it only focused on determining its durability through its water absorption
level as soaked in successive period of time. Meaning, the lesser water absorbed, the more durable
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the hollow blocks are. The lack of funds also hindered the researchers to standardly test the
reinforced hollow blocks from laboratories testing its durability accurately. Second limitation is
the weather condition.
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CHAPTER II
REVIEW OF RELATED LITERATURES
This chapter contains the review of related literatures and related studies.
Related Literatures
This study was anchored to the following literatures:
The use of aggregates for construction is one of the most important parts of construction
for it will add strength to the concrete. Finding a substitute for the aggregates used today is a task
that is worth studying because the quarrying of aggregates from the rivers and mountains harms
the environment. If a substitute for aggregate can be obtained naturally and the source is abundant
and can be regenerated, obtaining the aggregate would deplete its source.
The use of coconut shells and waste glasses has been a long-time source of income for
some people in the country. Using of recycled glass, as high performance by substitute for sand
and aggregates is being investigated in many years. Studies that already been conducted by
researchers had proven the use of waste glass and coconut shells as aggregates in concrete mixture.
The use of recycled glass in concrete opens a vast new market for waste broken glass in a variety
of specialty products or in local concrete operations. Recent research findings make it possible to
utilize glass in regular concrete applications, thereby expanding and developing markets for
recycled glass.
A glass is an inorganic non metallic material that does not have a crystalline structure.
Such materials are said to be amorphous and are virtually solid liquids cooled at such a rate that
crystals have not been able to form. Typical glasses range from the soda-lime silicate glass for
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soda bottles to the extremely high purity silica glass for optical fibers. Glass is widely used for
windows, bottles, glasses for drinking, transfer piping and receptacles for highly corrosive liquids,
optical glasses, windows for nuclear applications etc. etc.
In history, most products have been blown glass. In recent times most flat glass has been
produced using the float process. Mass produced bottles and decorative products are made using
industrial scale blown glass process. Hand blown glass items are made in art/craft centers
throughout the world.
The main constituent of glass is silicon dioxide (SiO2). The most common form of silica
used in glassmaking has always been sand. Sand by itself can be fused to produce glass but the
temperature at which this can be achieved is about 1700oC. Adding other chemicals to sand can
considerably reduce the temperature of the fusion. The addition of sodium carbonate (Na2CO3),
known as soda ash, in a quantity to produce a fused mixture of 75% Silica (SiO2) and 25% of
sodium oxide (Na2O), will reduce the temperature of fusion to about 800oC. However, a glass of
this composition is water soluble and is known as water glass. In order to give the glass stability,
other chemicals like Calcium Oxide (CaO) and magnesium oxide (MgO) are needed. The raw
materials used for introducing CaO and MgO are their carbonates, limestone (CaCO3) and
dolomite (MgCO3), which when subjected to high temperatures give off carbon dioxide leaving
the oxides in the glass.
Naohiro (1995), Park and Lee (2004), and Shayan and Xu (2004) have recently found out
some studies are carried out to suppress the ASR expansion in concrete and find method to recycle
waste glasses. The concrete containing 20% waste glass reduced the expansion ratio by 40%.
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Lee (2003) Commercial concrete hollow blocks were from three different retailers and
sellers of concrete hollow blocks. These commercial specimen samples were sent out for moisture
content and absorption tests. Try-out such as 1:0:6, 1: ½ :5 ½, 1:1:5, 1:1 ½ :4 ½ and 1:2:4 cementrecycled glass-sand ratios were subjected to absorption and moisture contents test after 28 days of
curing. The result of the specimens’ tests was then evaluated against ASTM C-129. When the
outcome of the test conforms to ASTM C-129, the mixture of the specimen was accepted.
In the construction industry, increasing attention is being paid to the concept of “green
buildings’. The search for “green” or environmentally friendly materials in the building industry
involves the development of new material but might also lead to the reconsideration of traditional
ones. The use of coconuts is used in many industries not only as food but for other uses as well.
The high cost of construction materials like cement and reinforcement bars, has led to increased
cost of construction. This coupled with the pollution associated with cement production, has
necessitated a search for an alternative binder which can used sorely or in partial replacement of
cement in concrete production. Coconut is famous as multi-functional that all parts of its plant can
be used for various activities. Considered the most useful tree in world, coconut palm provides
food, drink, clothing, shelter, heirloom history, and financial security. Hardly an inch of the
coconut palm goes to waste in countries such as the Philippines where families rely on the coconut
plan for survival and refer to it as the “tree of life”. The shell, husk, roots of the tree, fronds,
flowers, and the wood of the trunk are also become useful products. Building materials from
agricultural and forest wastes are ideal for socialized or low-cost housing since these are generally
cheaper than conventional materials.
Kulkarni (2013) Studied that aggregates provides volume at low cost, comprising 66% to
78% of the concrete. M20 concrete is produced by 0%, 10%, 20%, 30% replacement of coarse
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aggregate except for water absorption. No bond failure was observed, confirming that there was
adequate bonding between the coconut shells aggregate concrete and the steel bars.
Olanipekun (2006) carried out the comparative cost-analysis and strength characteristics
of concrete produced using crushed, granular coconut and palm kernel shell as substitutes for
conventional coarse aggregate. The main objective is to encourage the use of waste products as
construction materials in low-cost housing. Crushed granular coconut and palm kernel was used
as substitute for conventional coarse aggregate in the following ratios 1: 1: 2 and 1: 2: 4. Tot al
320 cubes were casted, tested and their physical and mechanical properties were determined.
Tukiman and Mohd (2009) replaced the coarse aggregate by coconut shell and grained
palm kernel in their study. Percentage of replacement by coconut shell were 0%,25%,50%,75%
and 100% respectively. Conclusion is that the combination of these materials has potential of being
used as light weight aggregate in concrete and also has reduce the material cost in construction.
Ries (2011) observed that lightweight aggregates play important role into day’s move
towards sustainable concrete. Lightweight aggregates contribute to sustainable development by
lowering transportation requirements, optimizing structural efficiency that results in a reduction in
the amount of overall building material being used, conserving energy, reducing labour demand
and increasing the life of structural concrete.
Kaur and Kaur (2012) published a review paper in which it is concluded the use of coconut
shells in cement concrete can help in waste reduction and pollution reduction. It is also expected
to serve the purpose of encouraging housing developers in investing these materials in house
construction. It is also concluded that the coconut shells are more suitable as low strength giving
lightweight aggregate when used to replace common coarse aggregate in concrete production.
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Kulkarni (2013) studied that aggregates provides volume at low cost, comprising 66
percent to 78 percent of the concrete. M20 concrete is produced by 0%, 10%, 20%30%
replacement of coarse aggregate except for water absorption. No bond failure was observed,
confirming that there was adequate bonding between the coconut shells aggregate concrete and the
steel bar.
Related Studies
This study is further anchored to following related studies:
The husk of a coconut comprises 30 per cent coconut fibers and 70 per cent flesh. Those
are separated from one another, after which traditional product, such as mats and brushes, are made
from the fibers. The flesh contains a significant amount of lignin, a substance that is found in
ligneous cell walls. In a melted form, that is suitable as an adhesive in the coconut fibers. (Van
Dam n. d).
Coconut Shell Powder were obtained from coconut shell that had been discarded and
grinded until it become in a form of powder. This study was conducted to determine the chemical
and physical properties of coconut shell powder to be used as a filler inside concrete. In order to o
that, an experimental setup of X-Ray Fluorescence (XRF), Particle Size Distribution, Scanning
Electron Microscopic (SEM), Density, and Specific Gravity were conducted. The coconut shell
powder consists mostly carbon (C) and potassium oxide (K2O). The presents of silicon dioxide
(SiO2) is crucial in order to be mix with concrete. The size of coconut shell is raging from 600µm
and below. From all the testing, it is shown that the coconut shell powder can be used in mixing
with concrete as a filler. (Leman, n. d.).
Properties of concrete with coconut shells (CS) as aggregate replacement were studied.
Control concrete with normal aggregate and CS concrete with 10-20% coarse aggregate
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replacement with CS were made. Two mixes with CS and fly ash were also made to investigate
fly ash effect on CS replaced concrete. Constant water to cementitious ratio of 0.6 was maintained
for all the concretes. Properties like compressive strength, split tensile strengths, water absorption
and moist migration were investigated in the laboratory. The results showed that, the density of
the concretes decreases with increase in CS percent. Workability decreased with increase in CS
replacement.
Since the focus of this study was to determine the effectiveness of adding of coconut shells
and waste glasses on the commonly used cement mixture, the researchers will test its durability
level using water absorptive capacity as measured the difference in mass.
Furthermore, by the facts presented above, and to help the economical state of community,
the researchers conducted a study recycling a waste. Thus, the researchers will entitle the study
“Coconut (Cocus nucifera) shell and waste glass as Reinforced Hollow Block Additives”.
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