soil reinforcement methods by natural means

1. Soil Stabilization using Natural Fibers and Waste Materials
Submitted by
VishwaleenVishaal Ram – 2016133741
Under supervision of
SupervisorMr. Sateesh Pisini
Submitted in Partial fulfillment of the Requirement for the Degree of
Bachelor of Civil Engineering (honors)
To
SCHOOL OF BUILDING AND CIVIL ENGINEERING
FIJI NATIONAL UNIVERSITY, FIJI ISLAND.

2. Table of Contents
CHAPTER ONE STUDYBACKGROUND................................................................................ 3
Purpose of the study................................................................................................................ 3
Methodology........................................................................................................................... 3
Objectives............................................................................................................................ 3
Research Gap.......................................................................................................................... 4
Engineering design.................................................................................................................. 4
CHAPTER TWO LITERATURE REVIEW.............................................................................. 4
Introduction............................................................................................................................ 4
Stabilizing Soil with Hair Fiber............................................................................................... 5
Preparing of Human Hair Fibers......................................................................................... 7
Mixing Human Hair Fiber Into the Soil............................................................................... 8
Effects of Soil Fiber Reinforcement on Shear Strength of Soil............................................. 8
Results of Different Testing on HHF Reinforced Soil.............................................................. 9
Results on Compaction Characteristics ............................................................................... 9
Results on Consistency Limits ........................................................................................... 10
Result on Compressive Strength........................................................................................ 10
Properties of Human Hair Fiber........................................................................................... 11
Properties of Soil................................................................................................................... 14
HHF Reinforced in Concrete................................................................................................. 15
Stabilizing Soil with other Natural Fibers ............................................................................. 16
Physical and Mechanical Properties of Natural Fibers. ..................................................... 17
Reinforcing Soil with Bamboo Fiber.................................................................................. 18
Reinforcing Soil with Jute Fiber........................................................................................ 18
Reinforcing Soil with Coir Fiber........................................................................................ 19
Reinforcing Soil with Palm Fiber....................................................................................... 19
Reinforcing Soil with Bagasse Fiber.................................................................................. 19
Reinforcing Soil with Rice Husk Fiber............................................................................... 20
Reinforcing Soil with Sisal Fiber ....................................................................................... 20
Behavior of Fiber Reinforced Soil...................................................................................... 20
Use ofModern Engineering and IT Tools ............................................................................. 22
Shear Strength Test........................................................................................................... 24
Saturated Test................................................................................................................... 24
Bearing Test...................................................................................................................... 25
Impact of Engineering on Society and the Environment ....................................................... 26
Reference .............................................................................................................................. 27

3. CHAPTER ONE STUDY BACKGROUND
Purpose of the study
Many engineers strive to obtain the maximum design capacity of soil stabilization due to
its softness, its calculations and its monotonous system. Therefore, reflecting the previous
difficulty faced by the engineers, I choose to adopt methods and materials to strengthen the
soil bearing capacity. There are many different natural fibers such as coconut fibers,
bamboo fibers, human hairs and other waste material like metal slug. So, I will be using
GeoStudio to obtain the interactive data queries to figure out the percentage of materials to
be used in the soil to give its ultimate capacity.
Methodology
Many natural resources are used and wasted with price in construction of building and
structures. The use of sustainable materials in the roads and foundation design of buildings is
counseled. A sequence of model test will be done on both road model and foundation model
that will be approved purchasable by means of the model test facility that will be developed
at the geotechnical laboratory, Department of Civil engineering, FNU. The collection of data
will be achieved from the site and the experiments done in the laboratory. Logical data from
the testing of soil will be obtained to do analysis in GeoStudio software. The results obtained
from the testing will be accumulated to be used in FLAC 3D. Experimental arrangements,
testing apparatus, sizes and experimental process will be established on the source of
objectives and probable results of this study
Objectives
Butt et al. (2016) stated that there are various ground improvement methods which have been
successful in the past years to improve the shear and bearing limits. Among various
reinforcing materials human hair fiber (HHF) can be used to enhance the shear and bearing
strength of clayey soil. Also sustainably use the material for development of infrastructures
reducing the disposal and pollution problem.
Results and Outcomes
The following specific outcomes may be expected from this research:
 Explaining the mechanism of sustainable stabilization of soil

4.  Working on model dimensions and experiment testing preparations
 Using of Geo-studio software for modeling and analysis for results
 Development of poster about sustainable soil stabilization methods and materials
 Midyear progress report
 Presentation of the project
ResearchGap
Gupta et al. (2018) explains that the sustainable soil reinforcement method has been the
subject for research in geotechnical field for many years. As the soil is reinforced with natural
fibers it requires less cost. The soil reinforcement method which actually increases the shear
and bearing strength. Therefore, this project is focused on the sustainable soil reinforcement
methods using natural fibers like human hair fiber.
Engineering design
The following steps are done to complete the soil reinforcement through the use of
geotechnical aspects.
1. Determining the soil type
2. Determining the landscape type
3. Choosing the type of natural fiber to use
4. Testing the strength of fibers
5. Comparing the test result of geotechnical test of reinforced and non-reinforced soil
6. Determining the application method to be used to reinforce the soil.
CHAPTER TWO LITERATURE REVIEW
Introduction
In many actions anxious with the use of soil, the physical properties like stiffness,
compressibility and strength are about of the few significant limits to be considered. Of the
numerous approaches intricate in the development of soil properties, soil reinforcement is
technique anxious with rise of strength properties of soil. In soil reinforcement, the
reinforcements basics are of different materials and various forms depending upon the
technique aim to use. The reinforcement can be on condition that permanently or
temporarily to rise strength of the adjacent structures. The present project discusses hair
fiber and waste materials on the application of soil reinforcement (Patil et al., 2016).

5. Distinctive fibers play a significant role in our daily life and perhaps all over the world with
not only straws of wheat, baggase, banana fiber, silk, cotton but even chicken feather pig,
hair and human hair as well. These have little density, economical cost, and easy
obtainability and actuality cast-off as composites since ages. These are overwhelmed goods
being created in tons round the year which makes environmental issues. The use not only
delivers an economical construction material but likewise equilibria the environmental
issues by using the waste in a useful manner. Human hair is recognized to be identical
strong in tension and is a substance which is non-biodegradable matter and effortlessly
obtainable. Fibers not only stop the cracks but also rise the tensile strength, strength in wear
and tear as well as fatigue resistance and ductility of reinforced material (Gupta and
Sharma, 2018).
Usage of fibers has an old history similar usage of horse hair and straw in clay for creation
floors and bricks and after 1964 steel fibers originated into practice as well. After that many
researchers have remained going over numerous studies to figure obtainable the use of such
fibers in refining the core strength of the matrices all over the world. Its effective usage in
structures for sustaining distinct obligation in structures has been fulfilled therefore in
forthcoming development can be very well understood in this way. There are 1.4 billion
people in the world who live below the international poverty line. Many social problems
that currently affect the world are caused by poverty, which causes the deficient access to
basic needs for many humans. The disaster that has been minimally addressed for low
income settlements is landslides on hillsides. Places with highest frequency of landslide are
mostly developing place (Gaw and Zamora, 2011).
Stabilizing Soil with Hair Fiber
To begin with, Wajid Ali Butt et al. (2016) states that geotechnical engineer has to
encounter challenges of construction of foundation at the places which are earlier
considered unsuitable and unacceptable. The weak soils or marginal soils lacks in strength
and bearing capacity, therefore becomes unsuitable for construction of structures on it.
There has been a lot of waste materials produced everywhere and its buildup in waste
streams causes many environment glitches. The fiber reinforcing of concrete started in the
1940s with lot of testing has been conducted in fibrous testing (Butt, Mir and Jha, 2016).
Moving on, Firoozi et al. (2017) shows that clayey soils are typically stiff when they are
dry and give up their stiffness as they become saturated. Soft clays are related with low
compressive strength and excessive settlement. The decrease in strength due to moisture
primes to damages in structures (Firoozi et al., 2017).
Furthermore, Brahmachary et al. (2018) found that, the underlying soil is not stable enough
to support the transfer of loads resulting in various type of failures. The later damage of
structures can cost a lot rather than continuing with the soil type one needs to ensure that
the soil is capable of withstanding the force (Brahmachary and Rokonuzzaman, 2018).
Moreover, the use of software is a challenge to analyze the strength and the bearing capacity
and other aspects of the soil. Many engineers face difficulties while modeling the complex
engineering problems that evolved from the soil experiments. Anon (2012) founded that it

6. is impartial to examine complex problems. Upon additional thought, the response develops
progressively multifaceted. Deprived of a clear sympathetic of the motive for modeling or
recognizing what the modeling purposes are, numerical modeling can prime us to
unsatisfying involvement and inexact outcomes. It is erroneous to setup the model; compute
a result and then attempt to choose what the outcomes mean. It is significant to choose at
the outset the motive for undertaking the modeling (Broaddus, M. (2015). Performing a
steady-state seepage analysis using SEEP/W : a primer for engineering students. Master
Thesis et al., 2012).
Additionally, this project boons the conclusion of casual addition of natural fibers on the
strength features of soil. In the vicinity existing cohesive soil is used as medium and natural
fibers with three facet ratios are used as reinforcement. soil is compacted with standard
Proctor’s determined density with little proportion of reinforcement 0-1%. Direct shear test,
unconfined compression tests and CBR tests remained directed on un-reinforced as well as
reinforced soil to examine the forte features of fiber-reinforced in the soil. The test
outcomes disclose that the presence of arbitrarily dispersed natural fibers in soil upsurges
the peak and residual shear strength unconfined compressive strength and CBR value of
the soil. It is seen that the optimum fiber contented for attaining the extreme strength is 0.4-
0.8% of weight of the oven-dried soil aimed at fiber aspect ratio of 100 as stated by (Butt,
Mir and Jha, 2016).
Likewise, Maity et al. (2018) considered that the fibers additional in subgrade building are
likely to deliver better compact interlocking system among fiber and the soil grain, better
resistance to deformation and faster indulgence of pore water pressure. The procedure aids
to consolidate and strong point the soil. There are many natural fibers such as jute, coir,
sabia grass and many more. These are economical and ecofriendly and grown abundance
in Fiji. It can be used as a stabilizer material in the subgrade soil to outcome rise in strength
and reduction in deformability. In this project the efficacy using natural fibers and waste
materials with locally available clayey soil has been studied. This application will ensure
the low cost in construction of civil structures for instance in construction of roads there
will be lesser thickness of pavement layers (Maity, J; Chattopadhyay, B C; Mukherjee,
2018).
In addition to this, Salazar et al. (2019) conducted a research on reinforcement of clayey
soils with crush polyethylene terephthalate. The use of plastic bottles as a material to
reinforce the clayey soil. The experimental study was done to appraise the mechanical
conduct of pure soil and combinations with different contents of PET, to get the desired
strength. The clayey soil used was assorted with 5%-20% of crushed PET by dry weight
(Salazar, Diaz and Ramirez, 2019).
According to Gaw et al. stated that this configuration has caused two main concerns among
experts. The first one is the clay soil significantly varies its moisture content because it
holds moisture according to the weather conditions.
Therefore, some part of Fiji is enclosed with clayey soil. These soils have swelling and
shrinkage features and shear strength is very little, later there is necessity for development
of these properties. Coir is the natural biodegradable material plentifully existing in some
parts of Fiji. This project intelligences the outcomes of comprehensive experimentation
researches by means of tri-axial shear tests, swelling, and consolidation tests to measure

7. the enhancements of strength, swelling and compressibility performance of clayey soil due
to the addition of coir fibers. This enables the usage of mixture of clayey soil and coir fibers
for sustainable development resolve.
Preparing of Human Hair Fibers
The fibers are known to be very flexible and strong. It is recommended testing the initial
moisture content of the fibers in order to rise the accuracy in the measurement of the
moisture content of the reinforced soil. It would also be beneficial to observe the absorption
capacity of the fiber and test any change in strength and stiffness. The fibers length varies
meaningfully and it is essential to cut them down to the essential length. The fiber can be
cut with scissor or other cutting device (Gaw and Zamora, 2011).
Human hair fibers will be obtained from the local baba shop, enough will be obtained for
the project. The dimeter will be measured for the five different selected fibers. Through the
handling of the fiber it will be evaluated qualitatively that the fibers had negligible moisture
content. The fibers length will vary between 1-4 inches.
Human hairs have been cast-off as fiber now and they have been washed as well after
assortment to eliminate any dust particles or any unwanted impurity existing and after
washing hairs are appropriately dried also under sun or in oven preferably must be sorted
such as they have uniform length so as to maintain and have an even and equal distribution
of hairs while fraternization with soil. Afterward drying hair can be kept without any matter
of odor and deterioration (Gupta and Sharma, 2018).
Figure 1 Photos of sized fibers used (Batebi et al., 2013)
Diverse values of fiber content implemented for present study were 0.5%-2.5% by weight of
soil. The fraternization of soil was felt very hard beyond 2.5% as some stick collected to form
lumps. This too produced pockets of low density, so it was absolute to stop with 2.5% fiber
content. Fibers were mixed to the moist mixture soil at diverse percentages and were tested as
per IS specifications. When fibers were varied in dry soil segregation and floating happened.
All fraternization was done by hand and proper care and time were used up for preparing

8. homogenous mix at each stage of mixing. It was initiate that the fibers can be blend with soil
more efficiently in the moist state than in dry state (Pillai and Ramanathan, 2012).
Figure 2 Human hair fiber (Pillai and Ramanathan, 2012)
Testing of Coated Human Hair Fibre
The life span of the hair fiber is about more than three years when buried and it is necessary to
find the preservation procedure for the fibers that did not suggestively lessening the strength
of the fibers. Another assortment principle was that coating should have no detrimental
influences on to the environment. Then a preservation is chosen and applied this preservation
is sorbic acid. It is applied since the coating has no significant effect on the fiber. The coating
would rise the service life of the fiber. Since there is less research done on these processes and
the coating effects on the preservation of fibers could not be resolute. It is not certain that the
fiber will be preserved for years but it’s a must that the coating will not affect the strength of
the fiber (Gaw and Zamora, 2011).
Mixing Human Hair Fiber Into the Soil
The combination of fibers into the soil outcome in the fibers to mass together above the soil
particles if the soil was not in the best moisture content or if large share of fibers were added
to the soil. It is suggested that attainment the soil best moisture content before the adding of
fibers. To attain the homogenous mixture the fibers must be stirred and the soil with diverse
movements. For big quantities of soil, it is suggested to use concrete mixer and for small
amount testing manually mixed by hand. It is also endorse to establish standard mixing process
based around mixing time and using the similar number of mixes (Gaw and Zamora, 2011).
Effects of Soil Fiber Reinforcement on Shear Strength of Soil
As stated by Gaw et al. (2011), using date palm fibers on a silty sand soil obviously specified
that in the reinforcement specimens wherever the soil grains are substituted by fibers, the fibers
switch the behaviours of the specimen. In this study a CBR test was done on 12 different wet
samples two switch groups and ten mixture of one of two dissimilar fiber lengths 20mm and
40mm and one of five different fiber contents 0.25%-1.5%. the CBR test penetration resistance
of a standard plunger on a soil sample. the focus is on the outcomes got on the wet samples
since the project will reflect failure below steady conditions. The figure below compares
different CBR stress applied by the piston to the penetration achieved by the plunger in six

9. different samples. The figure illustrates that the shear strength of the unreinforced wet soil at a
penetration of 13 mm is 6000 kPa and the shear strength of the reinforced soil with the
uppermost fiber content of 1.5% at the same penetration is 16000 kPa. The study protests that
the reinforcement of soil increases extra twenty times the penetration strength of a cohesive
soil (Gaw and Zamora, 2011).
Figure 3 (Gaw and Zamora, 2011)
Results of Different Testing on HHF Reinforced Soil
There are numerous tests that can be done in the lab to determine the results of HHF reinforced
soil. These tests may comprise consistency limits, compaction test, compressive strength test
and many more. The Atterberg’s consistency limits (liquid and plastic limit) be situated
resolute using Casagrande’s apparatus. The test was approved out with diverse portions of
human hair in soil. The proctor’s standard compaction test was approved out to control the max
dry density MDD and optimum moisture content (OMC) of together reinforced and
unreinforced soil. The soil mixes with and without fibers were carefully assorted with several
moisture content. The first series of compaction tests was designed to control the compaction
properties of clay upon fraternization with changing percentage of human hair fiber.
Unconfined compressive strength tests were led for numerous mix proportion of clay and
human hair fibers compacted to their supreme dry density (MDD) and OMC. All the specimens
were organized at a normal MDD and OMC of 1.6 g/cc and 22.5% (Pillai and Ramanathan,
2012).
Results on Compaction Characteristics
Proctor compact test were done in order to get the moisture content density relationship for the
mutually unreinforced and reinforced clay. After the test for unreinforced clay the MDD and
OMC were known out to be 1.64 g/cc and 20.64%. the result of addition of hair fibers in the
clay was known out by addition numerous quantities of fiber content. The standard proctor test
was directed with a primary goal moisture content of 18% with addition of 3% at the start
trailed by 2% at the ultimate densities. Two trials of test for apiece composition were directed
in directive to become more dependable outcomes for compaction. The properties of fiber
addition on the compaction behaviour for clay are in the figure below. It has been experimental
that the adding of arbitrarily spread HHF to clay with diverse percentage decreases MDD and

10. increases OMC. The trend to experimental is that both OMC and MDD was declining with
cumulative content of the fiber (Pillai and Ramanathan, 2012).
Figure 4 Compaction characteristics (Pillai andRamanathan, 2012)
Results on Consistency Limits
It was experimental that there was rise in liquid limit owing to adding of HHF which ascribed
to the fact that HHF engrossed moisture content inside the moist soil. The result of addition
of arbitrarily oriented HHF into the soil on the liquid limit, plastic limit and plasticity index
on the diverse soil mixtures are revealed in figure below. Likewise, it was experimental that
there was a minor reduction in the PL with the adding of reinforcement. Rise in plasticity of
HHF reinforced clay as an outcome of rise in LL and decrease in PL (Pillai and Ramanathan,
2012).
Figure 5 Variation of consistency limits (Pillai and Ramanathan, 2012)
Result on Compressive Strength
The fiber addition pretentious the stress-strain relationship of clay under static load by
growing the peak compressive strength, falling the post-peak decrease in compression

11. resistance and growing the engrossed strain energy. The typical stress-strain behaviour of
unreinforced clay and reinforced clay measured after unconfined compression test for the two
trials as shown in figures below. Since the failure pattern it is experimental that the
unreinforced specimens unsuccessful in shearing over a plain at 45 degrees and reinforced
specimen unsuccessful in compression by bulging of specimen (Pillai and Ramanathan,
2012).
Figure 6
Properties of Human Hair Fiber
The use of human hair fiber has good effect on the soils shear strength and the bearing
capacity. The soil used for the study is clayey in nature. Wajid Ali Butt et al. (2016)
investigated that entirely the necessary physical and mechanical properties were resolute
as per applicable standard tests (IS: 2720). The physical properties as described in table
below.
Table 1 Properties of Material Used
Source (Butt, Mir and Jha, 2016)

12. Moving on, many natural fibers are degradable and its strength and capacity degrade over
time. The human hair takes a lot of time to degrade, Wajid Ali Butt (2016) describes the
human hair thread is a natural fiber thread formed by keratin, a protein with a high grade
of sulfur. The main corporal property hinge on typically on its geometry. The mechanical
and physical properties of hair progress elasticity, smoothness, volume, shine and softness
due to both important adherence of the cuticle scales and the undertaking control as well as
the lenience of combing, since they decrease the fibers static electricity. The typical
structure of usual hair is unruffled of 45.68% carbon, 27.9% oxygen, 6.6% hydrogen,
15.72% nitrogen and 5.03% Sulphur (Choudhry and Pandey, 2012).
Furthermore, the hair fiber which is mostly finished of keratin protein with principally
alpha-helix structure about 91% of the hair is protein finished up of elongated chain of
amino acid the elongated chain linked by peptide bond. Amino acid existing in hair contain
cytosine, serine, glutamine, threonine, glycine, leucine, valine, arginine. The natural fibers
turn as probable reinforcement composites, bargain numerous compensations decent
strength properties, little cost, high durability, biodegradability, though, in the instance of
cellulose fiber some drawbacks owing to their intrinsic distinctive, unsuitability by
hydrophobic polymer matrix, propensity to form aggregates through dispensation and
deprived confrontation to moisture, limited length and big diameter, position an significant
challenge of their usage in progressive composite (Choudhry and Pandey, 2012).
Chaple et al. (2013) considered that the soil reinforcement is an active and dependable
method for refining strength and stability of soils. Numerous studies have been led to
examine the effect of arbitrarily concerned with discrete inclusions on very compressible
clayey soils. Coir is a natural bio-degradable material plentifully available in some parts of
Fiji. The current work is attentive on upshot of coir on bearing capacity and settlement of
footing with limits such as width of reinforced layer with 0.25%-1% of coir by means of
the laboratory model examinations on the square footings reinforced on extremely
compressible clayey soil reinforced with arbitrarily dispersed coir fiber. The provision of
coir reinforcement layer upsurges bearing capacity proportion up to 1.5-2.66. There is a
momentous rise in the bearing capacity of clayey soil through the presence coir fibers.
There is no essential to dwelling the fiber reinforced soil through the depth as well as the
soil is pretentious to a momentous complexity of 2-2.5 times the thickness of the footing.
The outcomes show that the reinforced layer decreases the settlement and enhances the
bearing capacity (Chaple, P. M., & Dhatrak, 2013).
In addition to this, Salazar et al. (2019) conducted an experiment where the enhancement
too hinges on upon the confining level which the trials were verified. By associating the
outcomes show that the mixtures with 20% crushed PET positions out contrary to the
others, since it has a better degree of enhancement in the soil. These mixes can be cast-off
in geotechnical applications (Salazar, Diaz and Ramirez, 2019).
The human hair fiber (HHF) holds keratin a protein that is accountable for the development
of human hair. Length of HHF is around 4 cm, diameter is 60-100 micro meter. HHF
generates environment problems, to diminish that it can be cast-off as reinforcement agent.
Addition of HHF to soil surges mechanical properties. The table below shoes the physical
properties of HHF (Manivel et al., 2017).

13. Table 2 Physical properties of human hair (Manivel et al., 2017)
Length (cm) 40
Diameter (micro meter) 60-100
Plastic modulus (G Pa) 3.5
Linear density (g/cm) 1.32
Yield strength (M Pa) 74.34
Breaking strength (M Pa) 119
Strain at break (%) 29
Tensile strength (M Pa) 384.79
Figure 7 Details of external surface hair (Batebi et al., 2013)
The key component of the hair composition is keratin. Keratin are proteins with extended
chains of amino acid that create the cytoskeleton of all cells of the outer shell. Quantity of
researches obviously quantified that sulfur is the main motive of strength of hair cords in
obverse of breakdown in the face of environmental stress and these sulfur compounds are
related with amino acids at very high stages in hair cords. Sulfur in amino acid molecules
is together to keratin protein till form disulfide performance nonetheless in alkaline
solutions they decompose. In datum, alkaline environment drops the hair cords (Batebi et
al., 2013).
The light weight, strength and deformation properties of fibers create them effective
materials in numerous foundation-engineering applications. Human hairs fiber was used

14. through this study to reinforce the soil. They are well-thought-out as valueless solid waste
which are actuality dumped to waste landfills. They contain of fibers of variable length 4-
40mm and diameter 40-111micro meter. Scanning electron microscope study was directed
to get the average diameter of human fiber. The limit of alarm in fiber selection was fiber
content by weight of the soil (Pillai and Ramanathan, 2012). The figure below shows the
Scanning Electron Microscope of human hair.
Figure 8 SEM image of human hair fiber(Pillai and Ramanathan, 2012)
Properties of Soil
The soil cast-off the current study is clay. Laboratory test to regulate various index and
engineering properties of clay were showed rendering to the Indian standard methods of
testing the table below reviews the numerous index and engineering properties of the soil.
the soil can be classified as clay with high plasticity (Pillai and Ramanathan, 2012).
Table 3 Properties of Clay (Pillai and Ramanathan, 2012)
Property Value
Specific gravity 2.57
Liquid limit 51%
Plasticity index 27%
Maximum dry density 1.64g/cc
Optimum moisture content 20.41%
% clay 68%
% silt 32%
% sand 0%
Cu at OMC 137.65kPa

15. HHF Reinforced in Concrete
To begin with, the use of HHF in concrete also improved in around places, the fiber
reinforced concrete is the one and only which contains cement, aggregates and some
uniformly distributed HHF. Concrete is by far one of the main materials used in building
construction whose compressive strength is finely recognized as well as its low tensile
strength approximately 10% of its overall compressive strength which ultimately leads to
racking and shrinkage of concrete. Usage of fiber reinforced concrete in structures also
reduces incidence of erosion specifically in hydraulic structures where flow velocity is
typically advanced. Also, the fiber reinforced concrete is lighter in weight as well as
additional workable. The fiber reinforced concrete with human hair as fiber is cast-off in
laying of runways, making pavements, tunnel lining, for construction and repairing of the
dams. Disposal of waste materials in large quantities has become an issue and this material
can be used as fiber for reinforcing the concrete (Gupta and Sharma, 2018). The below
table shows the results of compressive strength of the concrete mixed with HHF.
Table 4 Compressive strength at 28 days curing period with 1% hairs addition (Gupta and
Sharma, 2018)
S. No Concrete mix %hair Maximum load
recorded KN
Compressive
strength
KN/mm2
1 M20 0 392.62 17.45
2 M20 1 498.31 22.14
3 M30 0 537.25 23.87
4 M30 1 698.65 31.05
Table 5 Compressive strength at 28 days curing period with 2% hairs addition (Gupta and
Sharma, 2018)
S. No Concrete mix %hair Maximum load
recorded KN
Compressive
strength
KN/mm2
1 M20 0 392.62 17.45
2 M20 2 525.82 23.37
3 M30 0 537.25 23.87
4 M30 2 740.26 32.90

16. Moving on, for 28 days when M20 concrete by 1% hair s compared by the plain cement
concrete for the curing period of 28 days, it is known that there is an rise of 3.61% in
compressive strength by 2% hair is associated with the plain cement for 28 days curing
period, it is found that there is an rise of 8.68% in compressive strength. For the M30
mixture of concrete, after mixing M30 concrete with 1% hair is compared with the plain
cement concrete for the curing duration of 28 days, it is known that there is an rise of 1.57%
in compression strength with 2% hair is associated with the plain concrete for 28 days
curing period, it is known that there in as increase of 7.11% in the compressive strength
(Gupta and Sharma, 2018).
The possible influence of abridged strength in cement mortar is still a notable but it has to
remark that the resolution of this project is to study the impact of hair cord in controller of
shrinkage and cracks which are triggered in normal concrete. Previously the alkaline
environment lose the hair cords these cords may retort on purpose to their purpose to
prevent shrinkage (Batebi et al., 2013).
Stabilizing Soil with other Natural Fibers
Natural fibers are widely incorporated in many engineering applications. These fibers are
used due their abundance, cost effectiveness, sustainability, low density, stiffness, strength
and many more. The natural fibers can be divided in to three sections plant fibers, animal
part containing protein and minerals. Plant fibers can be used in soil reinforcement. Can be
classified into categories crop species, non-crop species, invasive species. Plant fibers may
be originated from stems, leaf, seed, fruit, wood, cereal straw and other parts. Move over,
the age of plant and how the fiber is treated, are some of the aspects which influence the
durability and performance of naturals fibers. Wood fiber has low intentions to be used as
it is difficult of frequent sourcing in large quantity, non-economic, low flexibility of fibers.
Below diagram shows the representation design for categorization of natural fiber
incorporated in the soil reinforcement (Gowthaman, Nakashima and Kawasaki, 2018).

17. Figure 9 (Gowthaman, Nakashima and Kawasaki, 2018)
Physical and Mechanical Properties of Natural Fibers.
As designing phase of soil reinforcement has not been directly joined with biochemical
composition, purpose and clarification of physical and mechanical properties of plant fibers
are very essential in civil engineering. The physical and mechanical properties are shown
in the table below. The bamboo and hemp along with flax and kenaf show more mechanical
strength limits amongst the potential natural fibers.
Table 6 Properties of plant fibers in reinforcing the soil. (Gowthaman, Nakashima and
Kawasaki, 2018)
fiber Density
kg/m3
Young’s
modulus
GPa
Ultimate
tensile
strength
MPa
Elongation
at break %
Moisture
absorption
%
Bamboo 715-1225 33-40 400-1000 - 40-52.45
Jute 1300-1450 10-30 393-860 1.5-1.8 12
Coir 1390-1520 3-6 100-225 12-51.4 130-180
Palm 463 26-32 100-400 19 1-10
Sugarcane
bagasse
1250 15-19 66.29-290 1.1 -
Water
hyacinth
800 - 295.5-329.5 13.6 32
Rice husk - - - - -

18. Sisal 700-1330 9-20 400-700 3.64-13 56-230
Flax 1500 27.6-80 345-1500 1.2-2.7 7
Banana 1350 27-32 711-779 2.5-3.7 -
Hemp 1140-1470 30-70 690-920 16 8-9
Kenaf 1040 136 1000 - 307
Pine 813 - 61.65 10.68 -
Barley 870 - - - 400
wheat 868 - - - 280-350
Reinforcing Soil with Bamboo Fiber
Bamboo is a plentiful and feasible natural resource and there are more than 1250 types in
the world. Bamboo-grid built with 1 cm diameter bamboo rods, would be suitable to control
the settlement of sandy silt 20-30% while settlement control by predictable geo-grid is only
10-15%. At the similar time bamboo grid controls the settlement and lateral distortion of
soft clay by about 21 and 31 percent. Normally, bearing capacity of the soil rises with
amount of grid layers practical within failure envelope and bamboo grid parades the
lowermost settlement and highest bearing capacity when the reinforced layer is positioned
at the depth of 0.3 B under the foundation whereas the b represents the foundation width
(Gowthaman, Nakashima and Kawasaki, 2018). Likewise, bamboo was cast-off in
challenging ground conditions, bamboo is a natural material that has more tensile strength.
The bamboo specimens that was coated with bitumen shows that soil reinforced with this
shows rise in bearing capacity. The performance of bamboo grid was initiate to be improved
than geogrid. Settlement of reinforced soil with Bamboo reinforcement of 1 cm diameter
was known to be decreased by 24% (Chacko and A, 2016).
Reinforcing Soil with Jute Fiber
Jute is one of the furthermost shared natural fiber crops being refined in the world, which
is comparatively inexpensive and commercially obtainable. Jute fibers have been initiated
to be active in refining geotechnical features of soil. Additional courtesies have been paid
on jute RDFS, application of woven jute textiles has been met as an economic and reliable
scheme in drainage applications. Basic assembly of jute textile consist approx. 40% direct
cover of jute yarns and 60% of open area, which benefits to control the velocity of ground
water flow thus harshly inhibiting the objectivity and conveyance of soil, interface
separator to avoid soil sand loss. Moving on, glued jute fabric has stayed recognized as
better jute textile material which shows high tensile strength when linked to that of jute reef
containing ten yarns. Strength conduct of jute RDFS in clayey soil has been studied with
diverse dosages 0.2-1% and diverse lengths 5-20mm and the finest strength value which is
around 2.5 time developed. Jute RDFS rises CBR about 50% when associated to normal
residual soil (Gowthaman, Nakashima and Kawasaki, 2018). Likewise, a general corrective

19. of jute fiber has given to the weakest soil, the jute is cast-off in diverse scopes of 0.25-0.5%
of weight of diverse lengths of 20-40 mm. trial outcomes show that CBR value of soil rises
with rises in fiber content. It was also detected that rise in length of fiber rises the CBR
value (Bundela et al., 2015).
Reinforcing Soil with Coir Fiber
Coir fiber is the material between hard-internal shell and external coat of a coconut, usually
arrays 0.1-0.3 mm and length ranges 10-50 mm. coir-textile has been applied as a shielding
material for slope soil as to guard the soil from erosion. Though, faster biodegradation of
coir fiber 22% of tensile strength only relics after 7 months of application. RDFS has
fascinated the purposes on soil reinforcing application these days. Nevertheless, treating
the coir fibers with both NaOH and CCl4 prior to the application enhances the reinforcing
effect in clayey soil. The general behavior of reinforced soil hinge on not only on the
optimum quantity of coir fiber nevertheless also the quality of treated fiber. Coir RDFS
rises the strength of expansive soil positively by 335% at optimal 0.6% short coir fiber
content. The coir fiber reinforcement rises the CBR value of granular subgrade by 96%.
Moving on, lateritic soil stabilization of little volume pavements propose that adding of 1%
coir fiber end to end with 3% cement by weight of soil rises the CBR values (Gowthaman,
Nakashima and Kawasaki, 2018).
Reinforcing Soil with Palm Fiber
Oil palm have its place to the kind Elaeis guineensis, which initiated from the tropical forest
of west Africa. Only very few studies have engrossed on the applicability of palm fibers in
the soil reinforcement methods. Palm random fibers reinforce soft shows optimum shear
performance at fiber content of 0.75%. though optimum CBR value of silty sand has been
stated at fiber content of 0.75% of 40 mm fiber length and attained penetration strength is
2.6 times higher than that of unreinforced soil (Gowthaman, Nakashima and Kawasaki,
2018). Likewise, oil palm empty fruit bunch was assorted with silty-sand soil to study the
rise in the shear strength through triaxial compression. Reinforced silty-sand comprising
0.5% coated fibers of 30 mm length showed approx. 25% rise in friction angle and 35% in
cohesion under undrained loading conditions related to those of unreinforced silty-sand.
The results specify that the shear strength limits of the soil-fiber mix can be enhanced
suggestively (Ahmad, Bateni and Azmi, 2010).
Reinforcing Soil with Bagasse Fiber
Bagasse fiber is a leftover material of the sugar cane industry. Bagasse has been recognized as
one of the possible materials to steady the expansive soils. Bagasse fiber reinforced clayey soil
shows a better control in shrink swell performance at 2% optimal content of fibers. At the same
time mixture of bagasse and lime encompasses the UCS by about 145% and lessens linear

20. shrinkage outcome associated to the reinforced by bagasse fiber alone (Gowthaman,
Nakashima and Kawasaki, 2018). Likewise, soil stabilization is most mutual ground
enhancement method, sequence of laboratory test was led to estimate the effect of bagasse
fibers. Changing proportions of arbitrarily dispersed bagasse fibers of 0.5-2% were additional
to expansive soil. The results of linear shrinkage, unconfined compressive strength tests after
numerous curing stages of 3, 7 and 28 days. The trial investigation indicate that bagasse fiber
reinforcement rises the compressive strength of expansive soils with rise in curing time and
additives contents, while the linear shrinkage of stabilized soils reductions with rise in fiber
proportions and curing stages (Dang, Fatahi and Khabbaz, 2016).
Reinforcing Soil with Rice Husk Fiber
Rice husk is a plentiful food waste with low price. The structure of rise husk is more complex
than other fibrous material, silica is 91.1% spread in rice husk. To current day there is only
limited learning on the applicability of rice husk fiber for soil reinforcing. Studies propose that
rice husk powder additives and curing duration effect an important result on the strength of
reinforced soil. Rice husk powder content of 15% with respect to 3 days curing has been
specified as optimal to get UCS of rice husk reinforced fine grained soil (Gowthaman,
Nakashima and Kawasaki, 2018). Likewise, the outcome of laboratory test showed on
expansive soil specimens treated with rice husk powder (RHP) and rice husk ash (RHA). The
quantity of RHP formed from the industry was 0-20% by weight. The treated specimen was
endangered to unconfined compressive strength, swelling test and Atterberg limit tests. With
rise in additive and curing duration the UCS rises (Canakci, Aziz and Celik, 2015).
Reinforcing Soil with Sisal Fiber
Sisal plant has been known as probable engineering material due to its strength durability
ability to stretch, resistance to weakening. Usually, adding of sisal fibers upsurge the ductility
of the soil without substantial consequence in compressive strength. The best length and
content of sisal fibers in RDFS technique have been accomplish as 20 mm and 0.75%, cohesion
of soil has been elevated by 265%. Though, rise of fiber length linearly reduces the MDD and
OMC. Sisal casual fibers shows better development of shear and deformation (Gowthaman,
Nakashima and Kawasaki, 2018).
Behavior of Fiber Reinforced Soil
Soil reinforcement can be defined as a method of improving the engineering characteristics
and conduct of soil by presenting the materials included of chosen properties. The main
objective of reinforcing soil mass is to improve its stability with shear and bearing capacity
overall to reduce the bearing capacity of soil. Fibers imbedded in soil can be wide-ranging
in forms, texture, stiffness, content, length or aspect ratio, and many more. The fiber
reinforced can be spread in two types oriented distributed fiber reinforced soil (ODFS)and

21. randomly distributed fiber reinforced soil (RDFS). The ODFS wherever naturals fibers can
be presented by planner system in vertical, horizontal or in both directions. The mechanism
of ODFS is alike to conventional geosynthetic and other. The ODFS method rallies
supplementary frictional strength laterally the fiber reinforced planes. Whereas the RDFS
is a well-recognized soil development method in which fibers encompassed of wanted
property and amount are assorted arbitrarily and compacted in situ. Short discrete fibers are
additional and mixed randomly with soil, much like the concrete mixing. It provides rise in
soil strength. The RDFS method exploits the alike behavior of plant roots. The diagram
below shows the ODFS and RDFS methods (Gowthaman, Nakashima and Kawasaki,
2018).
Figure 10 Fiber reinforcement mechanism of soil(Gowthaman, Nakashima and Kawasaki, 2018)
The diagram below shows schematic representation of a randomly distributed fiber unit,
part a showing the initial stage and part b showing the deformation stage because of the
loading. The result of interlocking friction and interface bonding persuades mobilization of
the tensile stress on the fiber unit as shown below in the diagram.

22. Figure 11 (Gowthaman, Nakashima and Kawasaki, 2018)
Use of Modern Engineering and IT Tools
The use of modern experimental equipment to analyze the strength of soil with and without
the natural fibers and other waste materials. There are many experiments that can be
conducted in the civil lab to get the outcome of the percentage to natural fiber such as the
human hair to reinforce the soil to increase the bearing capacity and the strength
respectively. The unparalleled computing power is now obtainable has occasioned in an
advanced creation for engineering and scientific analysis. The prepared obtainability and
ease-of-use of this products kinds it conceivable to use powerful methods such as a finite
element analysis and engineering practices. These analytical approaches are now
stimulated from actuality research tools to application tools. These has unlocked an entire
innovative world of numerical modeling.
Moving on, Farooq et al. (2015) used the Geo-Studio software for seepage analysis of
foundations using SEEP/W; a finite element software produced and could be used to model
the measure and pore water distribution within porous material such as soil and rock. It was
easy to analyze both simple and complex seepage problems through its wide-ranging

23. formulation. The finite element analysis can be agreed out by means of the SEEP/W
computer software in directive to appraise the effectiveness of cutoff with the depth of
permeable zone (Farooq, Tariq and Mujtaba, 2015).
Anon (2012) stated that using SEEP/W to do seepage analysis is about general numerical
modeling techniques. Numerical modeling is a talent that needs to be learnt. The modeling
necessitates cautious thought and planning and necessitates a good sympathetic of the
underlying fundamental theory and concepts. Steps in evaluating such as making the finite
element mesh and smearing boundary conditions are not completely instinctive at first.
Time and practice are essential to develop contented with these features of numerical
modeling. The investigation of flow through saturated and unsaturated soil by means of
numerical model is very non-linear problem that needs iterative methods to attain solutions
(Broaddus, M. (2015). Performing a steady-state seepage analysis using SEEP/W : a primer
for engineering students. Master Thesis et al., 2012).
Moreover, numerical modeling as an arena of exercise is moderately innovative in
geotechnical engineering and there is an absence of sympathetic around what numerical
modeling is, how modeling must be loomed and pardon to suppose from it. A good
sympathetic of these basic matters is important to leading operative modeling. The usage
of software is lone part of modeling workout. The allied mental investigation is significant
as clicking the buttons in the software.
Furthermore, there are three main parts to a finite element analysis. The first is making a
numerical domain, counting the selection of a suitable geometry and making the discretized
mesh. The second part necessitates the requirement of materials properties to numerous
sub-regions of the area. The third is the requirement of the suitable boundary conditions.
In addition, Wajid Ali Butt et al. (2016) founded that human hair were used as an improver
to high compressibility clayey soil by weight 0.5-2.5% to assess the effects of hair on the
mechanical performance of clayey soil. Entirely the samples were equipped at the OMC
and 0.95 cmax (MDD) as per IS:2720. The triaxial test cylindrical specimen of size 38.1mm
in diameter and 76.2mm in length is to be used. The CBR, the mould has inner diameter
150mm and height of 175mm for placing the CBR test specimen (Butt, Mir and Jha, 2016).
Likewise, Maity et al. (2018) experimented on CBR test and Unconfined compressive
strength assessment on in the vicinity accessible soil assorted with different kinds of natural
fibers for various length and quantity to study the progress of strength properties of fiber
soil composites located at optimum moisture content. From the test outcomes it was
experimental that there was a considerable rise in the CBR value for the clayey soil when
assorted with growing percentage of all three types of arbitrarily dispersed natural fibers
up to 2% of the dry weight of the soil (Maity, J; Chattopadhyay, B C; Mukherjee, 2018).
In addition to this, Salazar et al. (2019) conducted experiment on PET-soil mixture by doing
Atterberg’s limits and standard compaction test on the samples. Direct shear tests at vertical
stresses of 0.5 kg/cm2-2 kg/cm2 were completed on soil blends. The outcomes
demonstration that the soil strength limits are prejudiced by the addition of crushed PET,
meanwhile it progresses the features of friction angle and cohesion the soil-PET blends
(Salazar, Diaz and Ramirez, 2019).

24. The natural fibers were nominated and cast-off a 100% natural protection technique for the
assortment fiber, since there is a need to stop contamination the soil with detrimental
materials. Next the environment idea of decreasing the severe alterations to the landscape
as to not disturb the existing ecosystem, the purpose is to rise the shear strength of the soil
in the slope to lessen the grading course and the variation in runoff. The sustainability
constraint governs the design approach (Gaw and Zamora, 2011).
Shear Strength Test
The practice of unconfined compression test (UCT) to control the effect of the fiber on the
shear strength of the soil leads us to the decision that the reinforcement suggestively
advance the structural integrity of the soil. It can be settled that the optimum reinforcement
proportion by weight was 2% and the length of the fibers ought to be less than 50mm to
rise the consistency of the soil performance. Though, the test cannot deliver sufficient
information as to control the specific effect of fibers on the shear strength parameters of
soil. The triaxial test is suggested testing the effect of fiber reinforcement on the shear
strength of the soil. The test will deliver variation of horizontal and vertical compression
stresses that would let creating the cohesion and the friction angle of each soil conditions
that would let the modeling of performance of the soil below whole saturation.
Figure 12 shear strength test source: google
Saturated Test
The testing of totally saturated soil is very significant as it signifies one of the worst-case
scenarios for which urban planning must reason for. The soil samples were soaked in water
for 72 hours during the saturated test, for 72 hours it was cured inside a plastic bag to avert
the excessive evaporation of water. The samples were very hard to handle once they were
soaked. The soaking must take place in a non-vibration area as vibration may cause the soil
to collapse and gradually reduction the cross-sectional areas. The samples were extruded

25. after the soaking containers the bottommost layer of the samples would detach and loose
significant material (Gaw and Zamora, 2011).
Figure 13 saturated test source: google
Bearing Test
Throughout the design and research of the bearing capacity test it can be decided that
scaling down of all contributing basics so that none of them would apply unforeseen
pressures. Consequently, scaling down of fiber length to the similar scale as scaling down
the footing. Though, the particle size obligated to remain similar. Consequently, it is
suggested a study of scale result of composite soils on the bearing capacity of the model.
Around clear important increase in the soil bearing capacity tempted by the fiber
reinforcement. The soil container was intended for the test founded on an answer for
Bossinesq model of the inclined zone under a consistently distributed load. According to
this answer and the scale model the box would have not affected with the slip surface.
Though, none of the test offered a vibrant failure point. Previous studies that partake cast-
off similar bearing tests trials have cast-off soil containers of alike dimensions but made
out of stiff and apparent materials. These designs permitted the performers to clearly
control failure when a visible slip surface crack might be seen through soil walls. Failure
would be resolute when an extreme settlement of 1”/ scale factor was attained. This
approach was not accurate enough (Gaw and Zamora, 2011).
Figure 14 bearing test source: google

26. Impact of Engineering on Society and the Environment
The economic and social restraints were the foremost features in the strategy of the
project. The social restraint strongminded the population we meant to convey an answer
for. The chief apprehension is the high-risk circumstances in which these communities
grow their housing. The lack of resources accessible to these communities completed
the economic restraint the foremost principles in the assortment of the soil reinforcement
technique. The environmental and sustainability restraints were too portion of the
essential design. The environmental restraint controls the materials and process cast-off
for the soil reinforcement technique.

27. Reference
Ahmad, F., Bateni, F. and Azmi, M. (2010) ‘Performance evaluation of silty sand reinforced
with fibres’, Geotextiles and Geomembranes. Elsevier Ltd, 28(1), pp. 93–99. doi:
10.1016/j.geotexmem.2009.09.017.
Batebi, Y. et al. (2013) ‘Experimental Investigation of Shrinkage of Nano Hair Reinforced
Concrete’, Iranica Journal of Energy and Environment (IJEE), 4(1), pp. 68–72. doi:
10.5829/idosi.ijee.2013.04.01.11.
Brahmachary, T. K. and Rokonuzzaman, M. (2018) ‘Investigation of random inclusion of
bamboo fiber on ordinary soil and its effect CBR value’, International Journal of Geo-
Engineering. Springer Singapore, 9(1). doi: 10.1186/s40703-018-0079-x.
Broaddus, M. (2015). Performing a steady-state seepage analysis using SEEP/W : a primer
for engineering students. Master Thesis, 52. http://doi.org/10.18297/etd/2219 et al. (2012)
‘Seepage Modeling with SEEP / W 2015’, Geostudio Helpfile, (July), p. 199. Available at:
http://www.geo-slope.com.
Bundela, A. K. et al. (2015) ‘Identification of Weaker Subgrade Soil in Rajasthan and
Increment of CBR by Jute Fiber as Additive’, International Journal of Engineering
Technology, Management and Applied Sciences, 3(May), pp. 109–113.
Butt, W. A., Mir, B. A. and Jha, J. N. (2016) ‘Strength Behavior of Clayey Soil Reinforced
with Human Hair as a Natural Fibre’, Geotechnical and Geological Engineering. Springer
International Publishing, 34(1), pp. 411–417. doi: 10.1007/s10706-015-9953-x.
Canakci, H., Aziz, A. and Celik, F. (2015) ‘Soil stabilization of clay with lignin, rice husk
powder and ash’, Geomechanics and Engineering, 8(1), pp. 67–79. doi:
10.12989/gae.2015.8.1.067.
Chacko, S. S. and A, S. J. (2016) ‘Experimental Investigation on Soil Reinforced with
Bitumen coated Bamboo’, (2015), pp. 2015–2017.
Chaple, P. M., & Dhatrak, A. I. (2013) ‘Performance of Coir fiber Reinforced Clayey Soil’,
The International Journal Of Engineering And Science, 2(4), pp. 54–64.
Choudhry, S. and Pandey, B. (2012) ‘Mechanical Behaviour of Polypropylene And Human
Hair Fibres And Polypropylene Reinforced Polymeric Composites’, International Journal of
Mechanical and Industrial Engineering, 2(1), pp. 118–121.
Dang, L. C., Fatahi, B. and Khabbaz, H. (2016) ‘Behaviour of Expansive Soils Stabilized
with Hydrated Lime and Bagasse Fibres’, Procedia Engineering. The Author(s), 143(Ictg),
pp. 658–665. doi: 10.1016/j.proeng.2016.06.093.
Farooq, K., Tariq, K. A. and Mujtaba, H. (2015) ‘Evaluation of Seepage Reduction Measures
Under Dam Foundations Using Geo-Studio’, 67(2), pp. 182–191.
Firoozi, Ali Akbar et al. (2017) ‘Fundamentals of soil stabilization’, International Journal of
Geo-Engineering. Springer Singapore, 8(1). doi: 10.1186/s40703-017-0064-9.
Gaw, B. and Zamora, S. (2011) ‘Soil Reinforcement with Natural Fibers for Low-Income
Housing Communities’, Thesis wpi.edu, p. 147.
Gowthaman, S., Nakashima, K. and Kawasaki, S. (2018) ‘A state-of-the-art review on soil
reinforcement technology using natural plant fiber materials: Past findings, present trends and
future directions’, Materials, 11(4). doi: 10.3390/ma11040553.

28. Gupta, S. and Sharma, A. (2018) ‘Human Hair As Fibre Material in Reinforced’, in.
Maity, J; Chattopadhyay, B C; Mukherjee, S. P. (2018) ‘Improvement of Characteristics of
Clayey Soil Mixed with Randomly Distributed Natural Fibers’, Journal of The Institution of
Engineers (India): Series A; Dordrecht, 99(1), pp. 55–65.
Manivel, S. et al. (2017) ‘Experimental study on human hair fiber reinforced concrete with
partial replacement of cement by GGBFS’, International Journal of Civil Engineering and
Technology, 8(4), pp. 1145–1155.
Patil, P. et al. (2016) ‘Soil Reinforcement Techniques’, Journal of Engineering Research and
Application www.ijera.com, 6(2), pp. 25–31.
Pillai, R. R. and Ramanathan, A. (2012) ‘An Innovative Technique of Improving the Soil
Using Human Hair Fibers.’, in Third International Conference on Construction In
Developing Countries (ICCIDC–III) “Advancing Civil, Architectural and Construction
Engineering & Management”, pp. 428–434. Available at:
https://www.researchgate.net/publication/308791012_An_Innovative_Technique_of_Improvi
ng_the_Soil_Using_Human_Hair_Fibers.
Salazar, L. A., Diaz, F. R. and Ramirez, G. D. (2019) ‘Shear strength of a reinforced clayey
soil with crushed polyethylene terephthalate’, 2019 Congreso Internacional de Innovacion y
Tendencias en Ingenieria, CONIITI 2019 - Conference Proceedings. doi:
10.1109/CONIITI48476.2019.8960846.