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EXPERIMENTAL INVESTIGATION ON CEMENTITIOUS COMPOSITE
FORMULATED WITH POST-CONSUMER WASTE PLASTICS
BY
ADAMS, TAIWO DAVIDS
MATRIC. NO.: 110804003
SUBMITTED TO THE
DEPARTMENT OF CHEMISTRY
FACULTY OF SCIENCE, UNIVERSITY OF LAGOS, AKOKA.
IN PARTIAL FULFILMENT OF THE REQUIREMENT FOR THE
AWARD OF BACHELOR OF SCIENCE (B.Sc.) DEGREE IN THE
DEPARTMENT OF CHEMISTRY
OCTOBER 2015

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ABSTRACT
The report presented herein describes a laboratory investigation evaluating the performance of
post-consumer waste plastic (high-density poly ethylene) as replacement filler in a fibre-cement
composite.
The primary focus of the study was to gain some insights on the possibility and workability of
increasing the volume fractions beyond the range used in previous studies. To achieve this goal,
a coordinated experimental program was undertaken that consisted of the following phases:
i. Calorimetric assessment
ii. Selection of initial mix design
iii. Physicomechanical assessment
iv. Deterioration assessment
Measurements were carried out at room temperature and normal pressure. The obtained results
showed that the PCWP aggregates demonstrated that it is entirely possible to reuse such wastes
up to 60% composition within cement composites, without any further transformation beyond
pulverization, hence with minimal energy consumption.
These new composites would appear to offer an attractive low-cost material with consistent
properties; moreover, it would help in resolving some of the solid waste problems created by
plastics production and in saving energy.

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CHAPTER ONE
INTRODUCTION
1.0 INTRODUCTION
Over the past two decades, plastic waste has represented a significant portion of municipal solid
wastes. Landfill and incineration were the solutions initially proposed for handling such wastes
(Alter, 1993 and Yakowitz, 1990). Due to both the extended life cycle and visibility of the plastic
wastes, their management had become an environmental, economic and social imperative. A
complete waste management system including source reduction, reuse, and recycling was needed
to be implemented to control the increasing waste disposal problems (Carless, 1992). Of the
above options, recycling was the most promising waste management process for the disposal of
materials in the waste stream (Bell, 1990).
The construction industry turned out to represent one effective solution. The potential uses of
most recyclables in the construction industry are almost endless. Cementitious composites for
example have many applications such as thermal and acoustic insulation, fire resistant cladding,
etc., and have advantages, such as low density when compared to the concrete, better
performance to resist weathering, fire, fungi and insect attacks when compared to wood (Matoski
et al., 2007 and Sam et al., 2002).
1.1 COMPOSITES
A composite in engineering sense is any material that has been physically assembled to form one
single bulk without physical blending to form a homogeneous material. The resulting material
would still have components identifiable as the constituent of the different materials. One of the
advantages of composite is that two or more materials could be combined to take advantage of
the good characteristics of each of the materials. Usually, composite materials will consist of two
separate components, the matrix and the filler. The matrix is the component that holds the filler
together to form the bulk of the material. It usually consists of various epoxy type polymers but
other materials may be used. Metal matrix composite and thermoplastic matrix composite is
some of the possibilities. The filler is the material that has been impregnated in the matrix to lend
its advantage (usually strength) to the composite. The fillers can be of any material such as

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carbon fiber, glass bead, sand, or ceramic. Composites can be classified into roughly three types
according to the filler types: Particulate; Short fiber and long fiber.
Particulate composite consists of the composite material in which the filler materials are roughly
round. An example of this type of composite would be the unreinforced composite where the
cement is the matrix and the sand serves as the filler. Lead particles in copper matrix are another
example where both the matrix and the filler are metals. Cermet is a metal matrix with ceramic
filler.
Short and long fiber composites are composites in which the filler material has a length to
diameter ratio, l/d, greater than one. Short fiber composites are generally taken to have l/d of
~100 while long fiber type would have l/d ~ ∞. Fiber glass filler for boat panel is an example of
short fiber composite. Carbon fiber, aramid fiber (Kevlar®) fibers are some of the filler material
used in the long fiber type composites.
Since the composites are non-homogeneous, the resulting properties will be the combination of
the properties of the constituent materials.
1.2 FIBRE-CEMENT TECHNOLOGY
About 120 years ago, Ludwig Hatschek made the first asbestos reinforced cement products,
using a paper-making sieve cylinder machine on which a very dilute slurry of asbestos fibres (up
to about 10% by weight of solids) and ordinary Portland cement (about 90% or more) was
dewatered, in films of about 0.3 mm, which were then wound up to a desired thickness (typically
6 mm) on a roll, and the resultant cylindrical sheet was cut and flattened to form a flat laminated
sheet, which was cut into rectangular pieces of the desired size. These products were then air-
cured in the normal cement curing method for about 28 days.
The original use was as an artificial roofing slate. For over 100 years, this form of fibre cement
found extensive use, for roofing products, pipe products, and walling products, both external
siding (planks and panels), and wet-area lining boards. Asbestos cement composite was also used
in many applications requiring high fire resistance due to the great thermal stability of asbestos.
The great advantage of all these products was that: they were relatively lightweight; water
affected them relatively little, and they had a good resistance to biological damages, since the
high-density asbestos/cement composite is of low porosity and permeability.

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Over the course of the last century, two developments occurred that are of high significance to
modern replacements of asbestos based cement composites. The first was that some
manufacturers realized that the curing cycle could be considerably reduced, and cost could be
lowered, by autoclaving the products. This allowed the replacement of much of the cement with
fine ground silica, which reacted at autoclave temperatures with the excess lime in the cement to
produce calcium silica hydrates similar to the normal cement matrix. Since silica, even when
ground, is much cheaper than cement, and since the autoclave curing time is much less than the
air cured curing time, this became a common, but by no means universal manufacturing method.
A typical formulation would be 5-10% asbestos fibres, 30-50% cement, and 40-60% silica.
The second development was to replace some of the asbestos reinforcing fibres by cellulose
fibres from wood or other raw materials. This was not widely adopted except for siding products
and wet-area lining sheets. The great advantage of this development was that cellulose fibres are
hollow and soft, and the resultant products could be nailed rather than by fixing through pre-
drilled holes.
Later in the early 1980′s, health hazards associated with mining or being exposed to and
inhaling, asbestos fibers started to become a major health concern. Manufacturers of asbestos
cement products in the USA, some of Western Europe, and Australia/New Zealand in particular,
sought to find a substitute for asbestos fibers for the reinforcement of building and construction
products, made on their installed manufacturing base, primarily Hatschek machines. Over a
period of twenty years, two viable alternative technologies emerged, although neither of these
has been successful in the full range of asbestos applications.
In Western Europe, the most successful replacement for asbestos has been a combination of PVA
fibers (about 2%) and cellulose fibers (about 5%) with primarily cement, about 80%. Sometimes
the formulation contains 10-30% inert fillers such as silica or limestone. This product is air-
cured, since PVA fibers are, in general, not autoclave stable. It is generally made on a Hatschek
machine, followed by a pressing step using a hydraulic press. This compresses the cellulose
fibers, and reduces the porosity of the matrix. Since PVA fibers can't be refined while cellulose
can be, in this Western European technology the cellulose fiber functions as a process aid to
form the network on the sieve that catches the solid particles in the dewatering step. This product
has reasonably good biological durability due to its high density and non-biological degradable

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PVA fiber. The major application is for roofing (slates and corrugates). It is usually (but not
always) covered with thick organic coatings.
In Australia/New Zealand and the USA, the most successful replacement for asbestos has been
unbleached cellulose fibres, with about 35% cement, and about 55% fine ground silica. This
product is autoclave cured, as cellulose is fairly stable in autoclaving. It is generally made on a
Hatschek machine, and it is not usually pressed. The products are generally for siding (panels
and planks), and vertical or horizontal tile backer wet area linings, and as eaves and soffits in-fill
panels. The great advantage of these products is that they are very workable, even compared to
the asbestos based products, and they are low cost.
However, cellulose fibre cement materials had performance drawbacks such as lower rot
resistance and poorer long-term durability compared to asbestos cement composite materials.
These drawbacks are due in part to the inherent properties of natural cellulose fibres. Cellulose
fibres are comprised of primarily polysaccharides (cellulose and hemicellulose) and are highly
hydrophilic and porous, which in combination make them an attractive source of nutrients for
many microorganisms. As such, cellulose fibres are susceptible to bio-decay or rot attack when
incorporated into fibre reinforced cement composite materials, which also happen to be highly
porous. Particularly in high humidity environments, the pore spaces in the fibre reinforced
cement material facilitate water transportation to the fibres and thus provide access to
microorganisms such as fungi, bacteria, algae, and molds. Microorganisms can be carried by
water through the pores of the cellulose fibres. The organisms can grow on the surface and/or
inside the composite material by utilizing cellulose and hemicellulose as nutrients. The
microorganisms will break down cellulose polymer chains, resulting in significant loss in the
fibre strengths. The cleavages of cellulose fibre chains by the microorganisms eventually reduce
the reinforcement efficiency of the fibres and adversely affect the long-term durability of fibre
cement materials.
Accordingly, there is a need for a cost effective, fiber cement composite material that has
improved rot resistance. There is also a need for an individualized reinforcing fiber that retains
the advantages of cellulose and yet is more durable than regular cellulose fibers. To this end,
there is a particular need for a more cost effective and durable fiber reinforced cementitious
material that is resistant to microorganism attacks even in high humidity environments.

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1.3 CEMENT HYDRATION
Portland cement which is composed majorly of tricalcium silicate (C3S), dicalcium silicate (C2S),
tricalcium aluminate (C3A), tetracalcium aluminoferrite (C4AF) and gypsum (CSH2); is an
hydraulic cement. Hence, it derives its strength from chemical reactions between the cement and
water in a process known as “hydration”.
In the hydration of cement, the following series of reactions occur:
i. The tricalcium aluminate reacts with the gypsum in the presence of water to produce
ettringite and heat:
C3A + 3CSH2 + 26H  C6AS3H32 + ΔH
Once all the gypsum is used up as per reaction, the ettringite becomes unstable and reacts
with any remaining tricalcium aluminate to form monosulfate aluminate hydrate crystals:
2C3A + 3C6AS3H32 + 22H  3C4ASH18
ii. The tricalcium silicate (alite) is hydrated to produce calcium silicate hydrates, lime and
heat:
2C3S + 6H  C3S2H3 + 3CH + ΔH
iii. The dicalcium silicate (belite) also hydrates to form calcium silicate hydrates and heat:
C2S + 4H  C3S2H3 + CH + ΔH
iv. The tetracalcium aluminoferrite reacts with the gypsum and water to form ettringite, lime
and alumina hydroxides:
C4AF + 3CSH2 + 3H  C6(A,F)S3H32 + (A,F)H3 + CH
The ferrite further reacts with the ettringite formed to produce garnets:
C4AF + C6(A,F)S3H32 + 2CH +23H  3C4(A,F)SH18 + (A,F)H3
The hydration of cement can be thought of as a two-step process. In the first step called
“dissolution”, the cement dissolves, releasing ions into the mix water. The mix water is thus no
longer pure H2O, but an aqueous solution containing a variety of ionic species, called the “pore
solution”. The gypsum and the cement minerals C3S and C3A are all highly soluble, meaning
that they dissolve quickly. Therefore the concentrations of ionic species in the pore solution
increase rapidly as soon as the cement and water are combined. Eventually the concentrations
increase to the point that the pore solution is supersaturated, meaning that it is energetically
favorable for some of the ions to combine into new solid phases rather than remain dissolved.

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This second step of the hydration process is called “precipitation”. A key point, of course, is that
these new precipitated solid phases called “hydration products” are different from the starting
cement minerals. Precipitation relieves the super-saturation of the pore solution and allows
dissolution of the cement minerals to continue. Thus cement hydration is a continuous process by
which the cement minerals are replaced by new hydration products, with the pore solution acting
as a necessary transition zone between the two solid states.
1.4 RELEVANT STUDIES
The possibility of employing plastic wastes in cement composites has already been proven in
previous work (Andre and Fernando, 2010; Breslin et al, 1998; Flaga, 2000; Hinislioglu and
Agar, 2004; Liu, 1988; Naik et al, 1996; Rebeiz and Craft, 1995; Simonsen, 1996; Coatanlem et
al, 2006). In particular, the polyethylene terephthalate (PET) obtained from packing is
transformed into unsaturated polyester resin, in the presence of glycols, by means of the trans-
esterification process and then mixed with sand and gravel to produce a high-performance
material: polymer composite. In comparison with conventional Portland cement composite,
polymer composite is stronger in both compression and bending (Rebeiz, 1996) and features the
advantage of reaching over 80% of its ultimate mechanical strength within one day (Rebeiz,
1995) despite showing sensitivity to temperature (Vaverka, 1991). Other researchers have
focused their attention on the possibility of using PET wastes, mixed with high-density
polyethylene wastes (HDPE), as aggregates to be partially substituted for sand (between 5% and
20% as a ratio of total sand volume) (Avila et al, 2003). Their studies have shown that
volumetric substitution rates of up to 15% induce a decrease in the mechanical properties of new
composites, with respect to the control mortar, which does not contain any waste.
Byung et al., (2006) investigated the mechanical properties like compressive strength (73.7
MPa), flexural strength (22.4 MPa), splitting tensile strength (7.85 MPa), and elastic modulus
(27.98 GPa) at 7 days by adding an unsaturated polyster resin based on recycled PET in polymer
concrete.
Ochi et al., (2007) and Kenneth et al., (1999) described the method to prepare plastic fiber and
stated that these fibers can be easily mixed into concrete up to 3%.volume content and promising
results were obtained in compressive and flexure strength.

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Marzouk et al (2007), Ismail and Al-Hashmi (2008) studied the innovative use of consumed
plastic bottle waste as sand substitution aggregate within composite materials for building
application. Bottles made of polyethylene terephthalate (PET) were used as partial and complete
substitutes for sand in concrete composites. Various volume fractions of sand varying from 2%
to 100% were substituted by the same volume of granulated plastic, and various sizes of PET
aggregates. They concluded that substituting sand at a level below 50% by volume with
granulated PET, whose upper granular limit equals 5 mm, affected the compressive strength of
composites but plastic bottles shredded into small PET particles may be used successfully as
sand substitution aggregates in concrete composites. These composites appeared to offer an
attractive low-cost material with consistent properties; moreover, they would help in resolving
some of the solid waste problems created by plastics production and in saving energy.
Rafat et al., (2008) discussed the effect of recycled and waste plastic on workability, density,
compressive strength, splitting tensile strength. The post-consumer plastic aggregates used to
replace conventional aggregates and the compressive strength of concrete was in the range of 48
and 19 MPa. The splitting tensile strength was reduced by 17 % at 10% at plastic aggregates, but
ductile behavior of concrete was observed by them.
Sarda et al (2009) also concluded plastic strips have potential to act as secondary reinforcement.
From their study, the fibers made of recycled polyethelene teraphthalate (PET) are appropriate to
concrete reinforcement. The mixing ability of PET fibers is excellent and it is a promising
material to reinforce the concrete.
Venu and Rao (2010) used two polymer fibers PET in M30 grade of concrete. The workability
was reduced for higher percentage of fibers but the compressive strength was increased by
9.11% at 1% of PET fibers.
Prahallada and Prakash (2011) investigated that waste plastics can be used in fiber form to
improve properties of concrete. They observed that compressive as well as tensile strength of
waste plastic fiber reinforced concrete improved as compared to control concrete.

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1.5 AIM AND OBJECTIVES
The aim of this research work is to evaluate the possibility of incorporating volume fractions
beyond 50% of post-consumer waste plastic in fibre cement composites as a means to recycle.
Within this framework, the specific objectives of this study are:
i. To assess the chemical inertness of the post-consumer waste plastic aggregate towards
the cement matrix.
ii. To design an optimum mix.
iii. To evaluate the strength characteristics of the mix under flexural load deformation and
compressional toughness.
iv. To evaluate the gradual deterioration process of the composite mix.

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CHAPTER TWO
MATERIALS AND METHODS
2.0 MATERIALS
The materials used in this study include;
i. Portland cement
ii. Water
iii. Post-consumer waste plastic (HDPE)
iv. Polyvinyl Alcohol fibre (PVA)
2.1 METHODOLOGY
The experimental program consists of the following phases:
i. Calorimetric assessment
ii. Selection of mix design
iii. Physicomechanical assessment
iv. Deterioration assessment
2.1.1 PHASE I: Calorimetric Assessment
Calorimetric test were performed using a coffee cup calorimeter. This technique is based on
temperature change. It uses an insulated lid to prevent heat loss and a thermometer to measure
the temperature change. It works at atmospheric pressure which is assumed to be constant.

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Fig. 2.0 A schematic of the coffee cup calorimeter
The cement pastes were prepared by mixing thoroughly 400g of cement, 200mL of water and
30g of PCWP. The paste for reference comprised only 400g of cement and 200mL of water.
Pastes were worked out for about 5 minutes. Just after being prepared, the pastes were
transferred into the calorimeter. Temperature was then registered at 15 minutes intervals after the
first hour until it reached its peak and begins to drop. Tests results will be presented in the next
chapter.
2.1.2 PHASE II: Selection of Mix Design
Two sets of twelve beam specimens prepared in a split-type steel mould measuring
40×40×160mm were made by dry-mixing the cement, PCWP and fibre in a mixer according to
each mix proportion. After which predetermined amount of water was added gradually to the
materials, then mixed for an additional 5 minutes. The resultant mix resembled a zero-slump
composite-type mixture. The specimens were sealed cured in the laboratory environment for
about 24 hours after which they were de-moulded and allowed to cure at 100% humidity.

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Table 2.0 Summary of mix designs
Mixes Mix Design
Mix-1 25% Cement + 75% PCWP
Mix-2 25% Cement + 65% PCWP + 10% Sand
Mix-5 25% Cement + 75% Sand
Mix-6 25% Cement + 65% PCWP + 10% PVA
Mix-10 25% Cement + 10% PVA + 55% PCWP + 10% Sand
2.1.3 PHASE III: Physicomechanical Assessment
The strength characteristics of the beam specimens made from the mixes in phase II were
evaluated in terms of flexural load-deformation and compressional toughness using an ADR-
Auto 250/25 Cement Machine.
(a) (b)
Fig. 2.1 A schematic of the flexural and compressional strength test
Flexural strength under a three-point load capacity of 25KN was tested on the first set of beam
specimens, then compressional strength was tested on the second set of the beam specimens as
well as on the portions of the failed beams in the static flexure of the first set of specimens under

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a load capacity of 250KN. Tests were conducted under load control; no deformation
measurements were taken. Test result will be presented in the next chapter.
2.1.4 PHASE IV: Deterioration Assessment
Six cylindrical specimens prepared in a plastic mould measuring 65mm in diameter and 40mm in
height were made according to the procedure in phase II for mixes 1,5,6,10,11 and 12.
The specimens were conditioned to a constant weight at laboratory environment then subjected
to the accelerated aging test (soak-dry cycles) which consists of submerging the specimens into
water for 40hours, after which they are put into an oven at 100o
C of temperature for 5hours, to
make a cycle. Weight was observed for 10 cycles. Test result will be presented in the next
chapter.

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CHAPTER THREE
RESULTS AND DISCUSSION
3.0 RESULT OF PHASE I: Calorimetric Assessment
Calorimetry builds up a bridge between chemical and physical process and heat change which is
fundamental to understanding chemical reactivity and physical property. Calorimetric methods
are based on the exothermic nature of cement setting reactions. Thus, hindrance of cement
setting can be studied either by measuring the amount of heat evolved or by measuring the
evolution of temperature with time.
The lower the amount of heat evolved in comparison to the matrix, the more incompatible is the
given reinforcement. With temperature profiles, the higher the slope of the initial part of the
temperature vs. time plot, or the higher the temperature reached in the process, or the shorter the
time to reach the maximum of temperature, the less incompatible the reinforcing specie is.
Fig. 3.0 Temperature vs. time profiles for the setting of cement-paste only (T) and cement paste + PCPW
(T’)

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Fig. 3.1 Temperature vs. time profiles for the setting of cement-paste only (T) and cement paste + PCPW of
different mesh sizes: (T1 ≤ 2.38mm; T2 = 2.39mm – 3.36mm; T3 = 3.37mm – 4.76mm)
Fig. 3.2 Fig. 3.1 cropped out and enlarged.
From Fig. 3.0 above, one may conclude that the PCWP has no significant influence on the heat
of hydration of the cement, with no increase in heat capacity as the heat maximum is maintained.
However, Fig. 3.2 shows that the setting time is increased with increase in particle size. Thus,
PCWP does not pose any questions regarding its chemical inertness to cement.

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3.1 RESULT OF PHASE III: Physicomechanical Assessment
Table 3.0 Summary of 7days strength tests
Mixes Mix Design
Flexural
Strength
(MPa)
Compressional
Strength (MPa)
Fresh
Specimens
Failed
Portions
Mix-1 25% Cement + 75% PCWP 2.3 10.7 10.4
Mix-2 25% Cement + 65% PCWP + 10% Sand 2.8 14.3 14.0
Mix-5 25% Cement + 75% Sand 4.0 32.0 32.0
Mix-6 25% Cement + 65% PCWP + 10% PVA 2.6 7 6.1
Mix-7 25% Cement + 55% PCWP + 20% PVA 2.4 6.3 5.1
Mix-10 25% Cement + 10% PVA + 55% PCWP + 10% Sand 3.5 10.5 10.1
(a)

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(b)
Fig. 3.3 Strength chart for PCWP + Sand Mix
The replacement of the sand aggregate with PCWP lead to a decrease in the strength
characteristics of the composite mix, i.e. flexural and compressional strength decreases with
increase in PCWP. However, fibres can act as a primary reinforcement in artisan concrete
projects but only at a certain loading rate. To verify the rate, the effect of fibre was evaluated.
(a)

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(b)
Fig. 3.4 Strength chart for PCWP + PVA Mix
Unlike the unreinforced mixes that failed in a typical brittle manner characteristic of concrete-
type materials, it is observed that the fibre reinforced mixes demonstrated a post-peak load
bearing capacity. The fibers were able to delay the failure process.
Although the inclusion of fibers had a detrimental effect on the compressional strength of the
composite, a noticeable improvement was shown in the flexural strength up to 20% inclusion.
Nevertheless, 10% fibre content was considered to be the upper limit loading rate so as to ensure
workability of the mixes.
(a)

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(b)
Fig. 3.5 Strength chart for PVA + PCWP + Sand mix
To determine the best mix, both the strength and the toughness must be considered. Improved
toughness is considered to be a desirable characteristic for cementitious materials because the
higher energy absorption capacity of the material corresponds to increased resistance to fatigue
failure due to dynamic loading. Therefore, the best performing mixes are Mix-11 containing
“25% Cement + 10% PVA + 45% PCWP + 20% Sand” and Mix-12 containing “25% Cement +
10% PVA + 35% PCWP + 30% Sand” which achieved a flexural/compressional strength of
4.4/10.6MPa and 5.2/12.7MPa respectively.
3.2 RESULT OF PHASE IV: Deterioration Assessment
Table 3.1 Summary of accelerated aging test
Mixes
Initial Weight
(g)
Residual Weight
(g)
Weight Loss
(g) (%)
Mix-1 211.4 206.1 5.3 2.5
Mix-5 351.0 339.4 11.6 3.3
Mix-6 201.5 198.5 3.0 1.5
Mix-10 244.1 239.2 4.9 2
Mix-11 267.2 261.9 5.3 2
Mix-12 276.6 270.2 6.4 2.3

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The percentage weight losses in the specimens provide a measure of the relative deterioration of
the mix designs. It is observed that deterioration was concentrated on the exterior of the
specimen which was manifested in a form of surface erosion around the edges of the specimens.
The fibre reinforced specimens showed lesser signs of degradation unlike the unreinforced
specimens.

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CHAPTER FOUR
SUMMARY AND CONCLUSION
4.0 SUMMARY
It is generally recognized that the utilization of waste materials in construction is a
timely and desirable concept. However, caution must be exercised when incorporating recycled
materials with unknown or questionable properties or for which there is limited knowledge about
their long-term durability and performance characteristics. The idealized goal of incorporating
waste materials in cement composites must not be satisfied at the expense of building an inferior
composite, which will eventually contribute to infrastructural problems. Therefore, a careful
evaluation of all candidate waste materials should be performed before incorporating them into
the composite.
Accordingly, the current study was undertaken to evaluate an unconventional cement composite
consisting of recycled post-consumer waste plastic (PCWP), sand, cement, and polyvinyl alcohol
fibre. The focus of the experimental program was to gain some insights into the long-term
durability of this new composite base by performing short-term laboratory tests which included a
calorimetric assessment, flexural and compressional strength test as well as an accelerated aging
test. The optimized mix design concluded from this study is Mix-11which consist of 45% by
weight of PCWP, implying that at least 60% (by weight) of the aggregate was substituted.
4.1 CONCLUSION
The new composite therefore, has the potential for becoming an attractive alternative
construction material not only from environmental and economic standpoints, but also from
performance considerations.
The following are the significant conclusions derived from this experimental
investigation:
i. PCWP has no significant influence on the heat of hydration of the cement, with no
increase in heat capacity as the heat maximum is maintained.
ii. The curing time of cement is increased with increase in particle size.
iii. For the ranges in mix-designs used in this study, the fibre reinforced specimens under
flexural load deformation proved comparatively better than the unreinforced specimens.

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iv. The inclusion of fibers has a detrimental effect on compressive strength of the specimens.
v. The mode of failure was changed from brittle to ductile failure due to inclusion of fibre
into the specimen.
vi. 10% fibre content can be considered as the upper limit of fibre content to ensure
workability.
vii. The replacement of the sand aggregate with PCWP led to an appreciable decrease in
density.
viii. The performance of the proposed specimen under flexural load deformation as observed
from the experimental assessment is better than the control specimen.
ix. The fibre reinforced specimens absorbs lower moisture relative to the unreinforced
specimens.
x. The mechanism of deterioration occurs via surface erosion.

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