“STUDY ON DURABILITY TEST OF SUBGRADE SOIL

TREATED WITH ARECA NUT FIBRES AND POLYPROPYLENE

FIBERS FOR SOIL STABILIZATION”
A DISSERTATION WORK PHASE-1 REPORT SUBMITTED IN PARTIAL FULFILMENT
OF THE REQUIREMENTS FOR THE AWARD OF THE DEGREE OF

MASTER OF TECHNOLOGY –CIVIL

(MAJOR- HIGHWAY ENGINEERING)

Submitted By

NEHA .BV
(P25UV23T053003)
3rd Semester M.Tech
HIGHWAY ENGINEERING

Under the guidance of

Dr. L. MANJESH
Professor & Chairman
Department of Civil Engineering
University Visvesvaraya College of Engineering
Jnana Bharathi, Bengaluru -560056

UNIVERSITY OF VISVESVARAYA COLLEGE OF ENGINEERING

DEPARTMENT OF CIVIL ENGINEERING

JNANABHARATHI, BENGALURU-560056

2024-2025
 UNIVERSITY OF VISVESVARAYA COLLEGE
OF ENGINEERING
DEPARTMENT OF CIVIL ENGINEERING

CERTIFICATE
This is to certify that the Dissertation Work Phase-1 report entitled “STUDY ON DURABILITY
TEST OF SUBGRADE SOIL TREATED WITH ARECA NUT FIBRES AND
POLYPROPYLENE FIBERS FOR SOIL STABILIZATION” is submitted by Neha BV
(P25UV23T053003) in partial fulfilment of Master of Technology in Civil Engineering (Major:
Highway Engineering), during the academic year 2024-2025.

.................................................. ...................................................

Dr. L. MANJESH Dr .L . MANJESH

Guide & Professor Professor & Chairman
Department of Civil Engineering Department of Civil Engineering
University of Visvesvaraya College of Engineering University of Visvesvaraya College of Engineering
Bengaluru-560056 Bengaluru-560056

Examiners Signature

1. ……………………………………. .............................................

2. ……………………………………... ...............................................
 ACKNOWLEDGEMENT

I am greatly benefited under the valuable guidance and the suggestions of Dr. L MANJESH,
Professor and Chairman, Department of Civil Engineering, UVCE, Bengaluru for successful
completion of the dissertation work phase-1 report.

I am extremely thankful to Dr . L MANJESH, Professor and Guide, Department of Civil

Engineering, UVCE, Bengaluru for their support to complete the work.

I am thankful to Mr. NARESH YADAV T K Research Scholar, Department of Civil

Engineering, UVCE, Bengaluru their suggestions to complete the dissertation work phase-1 report.
I wish to thank my UVCE friends for their kind co-operation and encouragement rendered to me for
the successful completion of the dissertation work phase-1.

NEHA BV

(P25UV23T053003)

3rd SEMESTER

M.Tech, HIGHWAY ENGINEERING

SL No Description Page
No
CHAPTER 1
1 Introduction 1-6
1.1 General 1-2
1.2 Stabilisation of soil 3
1.3 Objectives of soil stabilization 3
1.4 Types of soil stabilization 4-5
1.5 Objective of the present study 5
CHAPTER 2
2 Literature survey 7-15
2.1 Literature review 7-15
2.3 Literature summary 16
CHAPTER 3
3 Experimental investigations 17
3.1 General 17
3.2 Methodology 18
3.3 Materials used 19
3.3.1 Sieve analysis of soils 20-22
3,4 Tests to be conducted on soils 22
3.4.1 Grain Sieve analysis of soil (IS: 2720 Part 4) - 1985 23
3.4.2 Atterberg limits 24-25
3.4.3 Compaction Test on Soils (IS: 2720 Part 7) 25-27
3.4.4 California Bearing Ratio (CBR) IS 2720 Part 16: 1987 27-28
3.4.5 Unified Compressive Strength of soil (UCS) (IS 2720 Part 10: 1991) 28-29
3.4.6 Freeze and Thaw test on soil sample IS : 4332 (Part 4) - 1968 30
CHAPTER 4
4.1 Test Results 31
4.1.1 Grain Sieve Analysis 31
4.1.2 Atterberg Limit 32-33
4.1.3 California Bearing Ratio (CBR) 34-35
4.1.4 Compaction test of soil 36-37
4.1.5 Unified Compressive strength test on soils 37
4.1.6 Unified Compressive strength test of soil mixed fibre 38-41
4.1.7 Durability test on soils 41-46
CHAPTER 5
5.1 Conclusion 46
CHAPTER 6
6.1 Reference 47-48
 LIST OF TABLES
SL No Description Page no
CHAPTER 3
3.1 Test Results of Sieve Analysis of Soils 20
3.2 Properties of Areca Fibres 21
CHAPTER 4
4.1 Grain sieve analysis 31
4.2 Liquid limit test of soil 32
4.3 Plastic limit of soil 33
4.4 CBR Test on soils for Soaked Condition 34
4.5 CBR Test on soils for Unsoaked Condition 35
4.6 Standard proctor (IS Light compaction) test for soil 36
4.7 Unified Compressive strength test of soil 37-38
4.8 Unified Compressive strength test of soil mixed fibre 38
4.9 UCS test on soil mixed with 1.5M of NaOH with 0.75% areca fibres 40
4.10 Freeze and thaw test on soil mixed without fibres 42
4.11 Freeze and thaw test on soil mixed with Areca nut fibres 43
4.12 Freeze and thaw test on soil mixed with Polypropylene fibres 45
4.13 Physical Properties of soil 47
 LIST OF FIGURES
SL No Description Page No
CHAPTER 3
3.1 Methodology 18

3.2 Soil collected from Ramanagara 19

3.3 Areca nut fibres extracted from areca nut shell 21
3.4 Soaking of areca fibres treated in NaOH and dried 22
3.5 Soil retained on different sieve size 24
3.6 Liquid limit test on soil 25
3.7 IS Light Compaction of soils (Standard Proctor test) 26
3.8 CBR test on soil 28
3.9 UCS test on soil alone 29
CHAPTER 4
4.1 UCS test mould to determine the optium fibres and optimum molarity 41
of NaOH
 CHAPTER 1

INTRODUCTION

1.1 GENERAL
The rapid growth of population, fast development of urban areas, and increase in
construction activities have resulted in the scarcity of land suitable for construction.
Structures frequently have to be built upon problematic (weak or expansive) soils. The
stabilization of soil with chemical additives helps to improve the engineering properties of
the soil. The common admixtures used to stabilize soil are lime, cement, ground granulated
blast furnace slag (GGBS), fly ash (FA), and bottom ash (BA). However, using lime and
cement raise environmental concerns and are not preferred nowadays. In the recent past,
sustainable binders have also been developed for the application in soil stabilization. Fibers
can be used as a reinforcing material in soil to impart tensile strength. Previous studies
reported the suitability of using synthetic fibres, such as polypropylene (PP), polyvinyl
alcohol (PVA), and natural fibres such as coir, jute, and sisal, among others, in soft ground
applications. oil stabilization is showing the promising results to achieve the shear strength.
n order to recover the soil properties to our specific needs, earth reinforcement is one of
the important techniques. Stabilization of soil has been done through different methods
depending upon our requirement and economy. Nowadays, with an increase in population
and in demand of shelters, soil stabilization gives a solution to recover the poor-quality
lands. In many parts of India soil consists of high finer fractions specially silt content, low
strengths and minimum bearing capacity. The performance characteristics of these soils
are analysed on the finer percentage in it. Soil is one of the most abundant and cheapest
construction materials. The knowledge of the use of soil as the construction materials dates
to prehistoric times, when man started constructing dwelling for living and roads for
transportation. During the last century, the rapid growth of civilization and urbanization in
many parts of the world has led to civil engineering projects in infrastructure and resource
development.

Often the “best sites or ideals sites” in terms of geotechnical engineer became a cause of
imagination now geotechnical engineers are faced with marginal sites with poor to
moderate soil conditions, i.e. sites having low bearing capacities, soils which are highly
compressible or any other type of problematic soils. When the load bearing capacity of the
soil is low, then shallow foundation is not possible in that locality. With the increase in

1
 construction activities both in onshore and offshore, stabilization with the advanced
techniques, gives an appropriate solution. Considering the ideal material for the foundation
and embankment construction, the soil should have adequate strength, should be relatively
incompressible and should have proper permeability. Most of the time we can’t find soil
satisfying all these needs. When the properties of soil stratum at site is up to level of
structural load, using chemical admixture, cement or lime stabilization techniques might
be adopted. Stabilization techniques also help to convert the natural property into our
specific needs, which leads to an economical foundation. Using dynamic compaction and
perforated vertical drains, Soil density could be improved in a great manner. The objective
of the present study to improve the engineering properties of the soil stratum. In such cases,
the properties of the soil should be improved by some means. All soils cannot be termed
as a problematic soil in certain environments. Soft clays are highly compressible and have
low bearing capacity. Stiff clays cause problems in diving piles. A silty soil offers better
strength in dry state and loses all strength at saturation. Loose soil is highly compressible
and has low bearing capacity, whereas dense sands cause problems in deep foundation
techniques.

1.2 STABILISATION OF SOIL

Soil stabilization is a general term for any physical, chemical, mechanical, biological, or
combined method of changing a natural soil to meet an engineering
purpose. Improvements include increasing the weight-bearing capabilities, tensile
strength, and overall performance of unstable subsoils, sands, and waste materials in order
to strengthen road pavements. Some renewable technologies are
enzymes, surfactants, biopolymers, synthetic polymers, co-polymer-based
products, cross-linking styrene acrylic polymers, tree resins, ionic stabilizers, fibre
reinforcement, calcium chloride, calcite, sodium chloride, magnesium chloride, and more.
Some of these new stabilizing techniques create hydrophobic surfaces and mass that
prevent road failure from water penetration or heavy frosts by inhibiting the ingress of
water into the treated layer.

However, recent technology has increased the number of traditional additives used for soil
stabilization purposes. Such non-traditional stabilizers include polymer-based products
(e.g. cross-linking water-based styrene acrylic polymers that significantly improve the

2
 load-bearing capacity and tensile strength of treated soils), Copolymer Based Products,
fibre reinforcement, calcium chloride, and Sodium Chloride.

1.3 OBJECTIVES OF SOIL STABILIZATION

 Enhance soil strength durability, and bearing capacity
 Reduce permeability
 Minimize issues like shrink/swell and erosion
 Ultimately ensuring a stable foundation for various structures and applications
 To cause economy within the cost of road.
 To form use of inferior quality of locally available soils/material.(whenever it's
impossible to seek out)
 Required or specified strength in locally
1.4 TYPES OF SOIL STABILIZATION
In construction projects soil or gravelly material is employed because the road main body
in pavement layers. to posses required strength against tensile stress and strain spectrum,
the soil used for roads and other construction should have special specification. Through
soil stabilization unbound materials are often stabilized soil materials have a far better
strength, lower permeability and lower compressibility than the native soil. There are
several methods for stabilizing soil, depending on the type of soil and the desired
properties. Here are the main types of soil stabilization:
 Mechanical stabilization
 Chemical Stabilization

 Mechanical stabilization: Mechanical stabilization is a method of soil

improvement that focuses on modifying the physical properties of the soil, such as
its structure, density, and particle composition, using mechanical methods and
equipment. This process doesn't involve chemical additives or biological agents
but instead relies on physical techniques like mixing, compacting, or adjusting the
size of soil particles. The goal is to enhance the soil’s load-bearing capacity, reduce
its permeability, and improve its overall strength and stability.

Advantages:
 Increases soil strength and stability.

3
  Reduces soil permeability, preventing water infiltration and erosion.
 Makes the soil more resistant to the effects of compaction under load (ideal for road
bases, foundations, and embankments).

Limitations:
 Not effective on highly expansive or swelling clays.
 Can lead to problems if over-compaction occurs, which might cause cracking or poor
drainage.

 Chemical Stabilization: Chemical stabilization is a process that involves adding

chemical agents to the soil to enhance its properties, making it more stable, durable,
and suitable for construction purposes. The primary goal of chemical stabilization is to
improve the soil’s strength, reduce plasticity (ability to deform without breaking), and
alter its behaviour to make it more resistant to environmental factors like water and
temperature. Chemical stabilization is especially useful for treating problematic soils,
such as expansive clays, loose sands, or silts, that don't naturally provide the necessary
strength or durability for construction.

Advantages:
 Cost-effective, as fly ash is a waste product and can be sourced cheaply.
 Improves the workability and compaction of soils.
 Reduces plasticity and increases soil strength and stability.
 Can be used to improve both fine-grained and coarse-grained soils.

Limitations:
 Fly ash is not always suitable for all soil types (e.g., it may not be as effective for sandy
soils).
 Variability in the chemical composition of fly ash can lead to inconsistent results.

1.5 OBJECTIVE OF THE PRESENT STUDY

 To evaluate the basic properties of the soil
 To conduct the basic test of the soil( like sieve analysis, Atterberg limits, CBR,
Hydrometer analysis, UCS(Unified Compression Tests of Soil))

4
 To determine the optimum moisture content and maximum dry density of the soil
without any stabilizers
 To evaluate the basic properties of the fibres
 To determine the optimum moisture content (OMC) and maximum dry density(MDD)
of the fibre
 To determine the molarity of NaOH
 To conduct the XRD(SEM analysis for the fibre mixed with soil sample)
 To conduct the durability tests on soil sample

5
 CHAPTER 2

LITERATURE SURVEY

2.1 Literature Review

Yowa Yaniam Ajanta Kalita et.al (2001) focused on Combined use of silica fume and Areca
fibre increases load-bearing capacity, making the stabilized soil suitable for heavier loads.
Silica fume provides resistance to chemical attack, increasing overall durability, especially in
aggressive environments. Areca fibre is a natural and renewable resource, offering an
environmentally friendly reinforcement option. Improvement in CBR values of 23.98% in
soaked condition up to 1.5% fibre inclusion in conjuction with 30% BA and 3% cement were
observed. Areca fibre have high tensile strength and thus resisted plunger penetration. Silica
fume enhances soil CBR value up to 3.07% of soil weight. 4. From triaxial shear test it is
observed that inclusion of fibre content significantly increases shear strength parameters (c and
φ) and soil stiffness modulus. The initial soil stiffness is 4581, and with the addition of 0.25%,
20mm areca nut fibre, it increases to 5406, indicating an 18% improvement in stiffness.

Lekha . M, S. Goutham, A.U.R. Shankar et al (2014) focuses on the durability test and
physical evaluation of soil cement mixtures reinforced with Areca nut coir. Coir content was
varied from 0.2% to 1% with an increment of 0.2%.

Chethan B A, A. U. Ravi Shankar, et.al (2002) focuses on using alkali-activated class F fly
ash binder with areca nut fibre as reinforcement was reported in this investigation. The effect
of stabilization was studied in terms of strength development, durability, and microstructural
changes. The following outcomes are highlighted. (1) Regardless of fly ash dosage, all alkali-
activated specimens attained maximum strength on 7 days of curing, and on further curing
slight increase in strength was noticed. (2) The use of areca fibre reinforcement has made the
specimens more ductile and reduced the density of mixes. However, the reinforcement has a
significant influence on improving flexural strength and the crack propagation resistance of
specimens. (3) Under the dry condition, the specimens showed a noticeable improvement in
plunger penetration resistance. The stabilized mixes exhibited excellent performance under the
fatigue load repetitions. (4) The alkali-activated BC soil with fly ash and areca fibres
reinforcement was highly susceptible to weathering due to seasonal changes associated with
wetting, drying, and frost actions like freezing and thawing. The leaching of minerals from the
set mix weakens the soil.

6
Ravi Diamond and Renjitha Mary Varghesh et.al (2021) aims on the addition of BA to Soil
till 25% has decreased the OMC , and increased the MDD , but this trend has been reversed
with the addition of 30% BA. 2. UCS of the soil-BA mix has been increased up to 25% BA
content, and there was a reduction in UCS with 30% BA 3. The results of UCS tests of the soil-
BA mix specimens with varying percentages of areca fibres shown that the addition of fibre-
enhanced the strength of the soil-BA mix significantly. 4. Addition of 1% areca fibre to Soil
has increased UCS values for 150 and 250 aspect ratio to 7% and 101% for a curing period of
28 days. 5. The inclusion of fibre has improved the crack resistance capacity greatly due to the
higher tensile strength of the Soil. under the range of fibre contents (0%~1%) tested in this
study as 1% gives optimum strength, crack reduction in the fibre-reinforced specimens
approached 42% and 51.5% reduction of CDF for 150 and 250 aspect ratio and CIF is reduced
by 68.8% and 76.8% for 150 and 250 aspect ratio, respectively. 6. The increase in the aspect
ratio reduced the CDF by 17.24%, average Crack width by 18.33% and average clod area by
11.2% due to increased surface contact and bonding strength between Soil and fibre.

Sooraj P. Sudhakaran, Anil Kumar Sharma et.al (2018) focuses on introducing a new
material, areca fibre and its suitability as soil reinforcement. Although areca is available
abundantly in many parts of the world, its application in geotechnical engineering has not been
explored. In the present study, bottom ash (BA) is used as a stabilizing agent, and the suitability
of natural areca fibre as reinforcement is demonstrated through detailed experimental
investigations and reliability analysis. The test method includes compaction tests, unconfined
compression strength (UCS) tests, California bearing ratio (CBR) tests, and split tensile
strength tests. The BA content was varied from 0 to 40%, the fibre content was varied from 0
to 1.5%, and the corresponding performance assessment was done. A small amount of cement
(3%) was also added to improve the pozzolanic reaction. The UCS and split tensile strength
tests were conducted on samples at different curing periods with a maximum curing for 90
days, whereas CBR tests were conducted after 7 days of curing for both soaked and unsoaked
conditions. There was considerable increase in UCS, CBR, and split tensile strength of the soil
with addition of BA, and the strength values increased tremendously in the presence of areca
fibre. Mineralogical and microstructural studies were conducted on the stabilized soil sample
using X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. These results
confirmed the formation of cementitious compounds in the XRD patterns and showed
development of dense matrix in the SEM images.

7
Sreevalsa Kolathayar , Swetha Prasanna et.al(2021) aims on the uncertainties in
geotechnical engineering are unavoidable. The soil properties may distribute within a
significant range over a domain. The soil is often very weak in tension and has less stability
under heavy loading. This paper presents stabilization of soil with bottom ash reinforcement of
soil with natural or synthetic fibres. Several reinforcing materials are available in the market,
but they are costly and not easily accessible. Bottom ash (BA) was used as a stabilizing agent,
and areca fibre was used for reinforcement, in this study. Polyvinyl alcohol (PVA), which is a
synthetic fibre, was also used to compare the performance of areca fibre. As compared to fly
ash, the use of bottom ash is minimal all over the world. This study determines the strength of
the soil stabilized with bottom ash and fibres at different proportions. The percentage of bottom
ash was varied from 0 to 40%; fibre proportion was varied from 0 to 2%.

Swetha Prasannan, Sreevalsa Kolathayar, Anil Kumar Sharma et.al (2020) study the
assesses the strength behaviour of bottom ash (BA)–stabilized soil mixed with different fibres
through a series of laboratory tests. Optimum BA and fibre percentage were obtained by small
scale lab tests like compaction tests and unconfined compressive strength (UCS) tests. From
compaction tests with varying proportions of BA (10, 20, 30, and 40 %), the optimum BA
content was found to be 30 %. With this optimum BA content, UCS tests were conducted on
soil-BA mix with different fibres (coir, areca, sisal, and polyvinyl alcohol) at various
percentages (0.5, 1, 1.5, and 2 %) to find the optimum fibre content. A set of model footing
tests were done to check the credibility of using fibres as a strengthening material beneath
footing to upgrade the engineering properties of soil to make a reasonable subsoil for the
foundation. A total of six model footing tests were performed on raw soil, on soil with optimum
BA content, and on BA–stabilized soil mixed with different fibres in their optimum percentage
(1.5 %). The bearing capacity of unstabilized unreinforced soil was found to increase
significantly with the inclusion of fibres.

Kiran, Harsha S ,Dr. K V S B Raju ,Naveen et.al (2018) describes about the exploratory
examination on the adjustment of soil utilizing the Byproduct of Sugarcane handling and Areca
Nut strands. The Byproduct of Sugarcane preparing thought about was Molasses. The Molasses
principally contains Silicon Di oxide, Potassium oxide and Calcium Oxide. Fundamental
properties of virgin soil like Atterberg points of confinement, compaction attributes, California
bearing proportion, and unconfined compressive quality were resolved. The dirt example was
treated with differing rates (2%, 4%, 6%, 8% & 10%) of Molasses and the ideal level of
Molasses for the dirt was resolved. The dirt example was again treated with differing rates of

8
Areca Nut strands (1%, 2%, 3% & 4%) and the ideal level of Areca Nut strands for the dirt was
resolved. The dirt was then treated with ideal level of Molasses and differing rates of Areca
Nut strands. It was watched that the dirt demonstrated impressive quality change with Molasses
and Areca Nut filaments. The viable utilization of locally accessible materials like Molasses
and Areca Nut strands for the change of soil makes the examination significant and attainable.

Jyotesh Kumar Choudhary, Udai Kumar Singh et.al (2021) describes the main objective of
this project is to investigate the effect of waste polypropylene fibre as a reinforcement by
conducting compaction characteristics, Unconfined compressive strength, Direct shear test,
and California bearing ratio for soil with randomly distributed small percentages (0%, 0.10%.
0.20%, 0.30%, 0.40% & 0.50%) of fibre. There is a rapid increase in plastic waste generation
all over the world and the correct manner of disposing is very challenging as it is non-
biodegradable and have very low recycling ratio ultimately causing ecological hazards. Soil
stabilization by conventional methods using cement, lime fly ash as an admixture is not
economical in recent years, so there is a need to look after for an alternative such as plastic.
Fiber reinforcement emerged as an important method for improving the properties of soil. So,
in this study we use waste polypropylene fibre and conducted various experiments to find
optimum amount which will give the maximum enhancement in the strength of soil.

Muttana S. Balreddy , Sanjay S Sajjan, Dayananda Pruthviraja et.al (2024) states that
this has led to the development of several stabilization techniques that can be used to improve
the properties of weaker soils for construction. The research presented here explores the impact
of inducing randomly oriented alkali-treated areca fibres for stabilization of silty sand soil. A
sequence of experiments was carried out on the soil-fibre mixtures to investigate the strength
of the soil after stabilization. At increments of 0.2%, the fibre dose varied between 0 – 0.8% of
the dry weight of the soil. The tests conducted includes compaction tests, California bearing
ratio (CBR), unconfined compression strength (UCS) tests, and unconsolidated undrained
(UU) triaxial tests. The results obtained showed a notable increase in the strength of the soil-
fibre mixtures. An increase in fibre content was found to increase the OMC (optimum moisture
content) values and decrease the MDD (maximum dry unit weight) values. The maximum
strength of the soil-fibre mixture was obtained at 0.6% fibre content. This makes it possible to
use silty sand soil subgrades for low-volume roads with a traffic of less than 2 million standard
axles based on the IITPAVE analysis. In essence, the test findings indicated that the ideal fibre
content to be 0.6%. Stabilization of local on-site soils is one of the sustainable practices that

9
can help extend the life of a pavement and lessen the need for more frequent
repairs/maintenance.

Gümüşer C, A. Şenol2 et.al (2013) focuses on the total coal and lignite consumption of the
thermic power plants in Turkey is approximately 55 million tons and nearly 15 million tons of
fly ash is produced. The remarkable increase in the production of fly ash and its disposal in an
environmentally friendly manner is increasingly becoming a matter of global concern. Studies
for the utilization of fly ash in Turkey are necessary to reduce environmental problems and
avoid economical loss caused by the disposal of fly ash. Efforts are underway to improve the
use of fly ash in several ways, with the geotechnical utilization also forming an important aspect
of these efforts. An experimental program was undertaken to investigate the effects of
Multifilament (MF19average) and Fibrillated (F19average) polypropylene fibre on the
compaction and strength behaviour of CH class soil with fly ash in different proportions. The
soil samples were prepared at three different percentages of fibre content (i.e. 0.5%, 1% and
1.5% by weight of soil) and two different percentages of fly ash (i.e. 10% and 15% by weight
of soil). A series of tests were prepared in optimum moisture content and laboratory unconfined
compression strength tests, compaction tests and Atterberg limits test were carried out. The
fibre inclusions increased the strength of the fly ash specimens and changed their brittle
behaviour into ductile behaviour.

Muhammad Ali1a, Mubashir Aziz , Muhammad Hamza et.al (2020) focuses on the
expansive soils are renowned for their swelling-shrinkage property and these volumetric
changes resultantly cause huge damage to civil infrastructures. Likewise, subgrades consisting
of expansive soils instigate serviceability failures in pavements across various regions of
Pakistan and worldwide. This study presents the use of polypropylene fibres to improve the
engineering properties of a local swelling soil. The moisture-density relationship, unconfined
compressive strength (UCS) and elastic modulus (E50), California bearing ratio (CBR) and
one-dimensional consolidation behaviour of the soil treated with 0, 0.2, 0.4, 0.6 and 0.8% fibres
have been investigated in this study. It is found that the maximum dry density of reinforced soil
slightly decreased by 2.8% due to replacement of heavier soil particles by light-weight fibres
and the optimum moisture content remained almost unaffected due to non-absorbent nature of
the fibres. A significant improvement has been observed in UCS (an increase of 279%), E50
(an increase of 113.6%) and CBR value (an increase of 94.4% under unsoaked and an increase
of 55.6% under soaked conditions) of the soil reinforced with 0.4% fibres, thereby providing a
better quality subgrade for the construction of pavements on such soils. Free swell and swell

10
pressure of the soil also significantly reduced (94.4% and 87.9%, respectively) with the
addition of 0.8% fibres and eventually converting the medium swelling soil to a low swelling
class. Similarly, the compression and rebound indices also reduced by 69.9% and 88%,
respectively with fibre inclusion of 0.8%. From the experimental evaluations, it emerges that
polypropylene fibre has great potential as a low cost and sustainable stabilizing material for
widespread swelling soils

Mona Malekzadeh, Huriye Bilsel et.al (2007) focuses on the experimental study evaluating
the effect of polypropylene fibre on mechanical behaviour of expansive soils. The initial phase
of the experimental program includes the study of the effect of polypropylene fibre on
maximum dry density and optimum moisture content with different fibre inclusions. Dynamic
compaction tests have been conducted on an expansive soil sample with 0%, 0.5%, 0.75%, and
1% polypropylene fibre additions (by dry weight of the soil) and samples have been prepared
with the same dry density statically. The second phase of the experimental program focuses on
the unconfined compression, tensile and one-dimensional swell behaviour of the unreinforced
and reinforced soil samples. Finally it is concluded that mitigation of expansive soils using
polypropylene fibre might be an effective method in enhancing the physical and mechanical
properties of subsoils on which roads and light buildings are constructed.

Mona Malekzadeh & Huriye Bilsel et.al (2012) focuses on the paper presents an
experimental study evaluating the effect of polypropylene fibre on swell and compressibility
of expansive soils. The initial phase of the experimental program includes the study of the
effect of polypropylene fibre on maximum dry density (MDD) and optimum moisture content
(OMC) with different fibre inclusions. Static and dynamic compaction tests have been
conducted on an expansive soil sample with different percentages of 0%, 0.5%, 0.75%, and 1%
polypropylene fibre additions (by dry weight of the soil). The second phase of the experimental
program focuses on the compressibility and hydraulic characteristics of the soils. The
unreinforced and reinforced specimens have been prepared statically and the swell and
compressibility behaviour of the samples have been analysed. Finally it is concluded that
mitigation of expansive soils using polypropylene fibre might be an effective method in
reducing the swell potential and compressibility of subsoils on which roads and light buildings
are constructed.

Mazahir M. M. Taha, Cheng Pei Feng, Sara H. S. Ahmed et.al (2020) focuses on the
investigating the effects of polypropylene fibre (PF) reinforcement on the mechanical

11
behaviour of clay soil. Using clay soil and polypropylene fibres from China’s Inner Mongolia
and Hebei Provinces, respectively, a series of soil samples with 0%, 1.5%, 2.25%, and 3% PF
content by soil weight were subjected to compaction, shear strength, consolidation, California
bearing ratio, and microstructure analyses. The study results indicate improved compaction,
shear strength, consolidation, and the bearing ratio of the PF-stabilised clay soil. As the PF
content increased, its maximum dry density increased and its optimum moisture content
decreased; its angle of internal friction increased and its cohesion coefficient decreased; and its
void ratio, consolidation coefficient, and hydraulic conductivity all decreased. Comparing the
unstabilised (0% PF) and stabilised (3% PF) clay soil, the void ratio, consolidation coefficient,
and hydraulic conductivity decreased from 0.96 to 0.93, from 2.52 to 2.34 cm2/s, and from 1.12
to 1.02 cm/s, respectively. The optimum PF content was determined to be 3% by the weight of
the soil, as this quantity resulted in the best improvement in soil properties.

Kavitha M S , B. Shaik Mohamed, C. Muniyappan et,al (2019) focuses on the various

problems while designing foundation because of clayey soil due to poor bearing capacity and
excessive settlement. So, we rectify that with various engineering works but in this project we
choose fibres for improving soil parameters, this method is cost-effective and eco-friendly one.
The clay sample was collected from Devakottai, Tamil Nadu, and India. Sisal, polypropylene,
and hybrid of these two fibres were used for soil stabilization. The sisal fibre was mixed 0 .1%,
0.2%, 0.3% and 0.4% by weight of the soil samples. Similarly, polypropylene fibre was mixed
0.5%, 1%, 1.5% and 2% by weight of the soil samples and hybrid fibre mixed soil samples
randomly distributed. The effect of fibre addition on soil stabilization was evaluated by
conducting tests such as Atterberg’s limits, Standard Proctor compaction test, Unconfined
Compressive strength test, Specific gravity test, and California bearing ratio test.

Yasir Hussain, Harvinder Singh et.al (2020) aims on the study of coir along with
Polypropylene Fibre (PF) is used as a stabilizing agent to enhance the particle bonding. The
fibres are added in percentage of 0.25 %, 0.50%, 0.75%, and 1%. The experiment shows that
Maximum Dry Density, CBR and shear strength is obtained maximum at 0.75% of fibre content
and hence considered as the best ratio to enhance the soil properties.

Pradip Kumar Pradhan, Rabindra Kumar Kar , Ashutosh Naik et.al (2012) focuses
on effect of random inclusion of polypropylene fibres on strength characteristics of soil.
Locally available cohesive soil (CL) is used as medium and polypropylene fibres with three
aspect ratios (l/d = 75, 100 and 125) are used as reinforcement. Soil is compacted with standard

12
Proctor’s maximum density with low percentage of reinforcement (0–1% by weight of oven-
dried soil). Direct shear tests, unconfined compression tests and CBR tests were conducted on
un-reinforced as well as reinforced soil to investigate the strength characteristics of fibre-
reinforced soil. The test results reveal that the inclusion of randomly distributed polypropylene
fibres in soil increases peak and residual shear strength, unconfined compressive strength and
CBR value of soil. It is noticed that the optimum fibre content for achieving maximum strength
is 0.4–0.8% of the weight of oven-dried soil for fibre aspect ratio of 100.

Rao Asha Uday ,Dhanalakshmi Kiran , Arun Kumar G S et.al (2023) focuses on soil
stabilization method aids in achieving the essential soil qualities for building operations.
Expansive soils, also known as swelling soils or shrink-expand soils, are soils that swell and
shrink in response to changes in moisture content. As a result, major soil distress ensues,
resulting in severe damage to the underlying structure. The impacts of polypropylene fibre on
the geotechnical parameters of locally accessible Black Cotton (BC) soil near Haveri city,
Karnataka, India, were investigated in this study. The soil sample was subjected to tests to
determine its consistency limits, specific gravity, compaction, California bearing ratio,
unconfined compressive strength, and shear strength. These experiments were carried out on
both non-stabilized and stabilized soil by substituting 0%, 0.50%, 1%, 1.50%, 2%, 2.50%, and
3% of polypropylene fibre. The results show that polypropylene fibres improves several
geotechnical parameters at various soil replacement percentages. The 2.5% of replacement is
the best solution and an optimum replacement for different kinds of geotechnical-related works
using this BC soil. The correlation between the different parameters is also determined from
the analysis.

Manish Kumar Upadhyaya , Amit Daiyaa , Jitendra Khattib et.al (2019) focuses on
comparative study of stabilization of black cotton soil by natural and artificial fibre. Natural
fibres are those which is obtained from nature i.e. coconut fibre, jute fibre, sisal fibre etc. and
artificial fibres are those which is manmade i.e. nylon fibre, polypropylene and polyethylene
terephthalate etc. Many researchers performed experiments on stabilization of black cotton soil
by natural fibre, artificial fibres and combination of different admixture with fibres. The study
of liquid limit, plastic limit, standard proctor test and California bearing ratio test is also done
for different types of fibre and conclusions are mapped. From study the statement is made that
artificial fibre may decompose gradually compare to natural fibre.

13
Himanshu gupta, Manoj sharma et.al (2017) focuses on the properties of soil do not change
only with location to location but also with respect to depth, climate and drainage condition of
soil. Soil stabilization is the process by which strength properties of soil can be improved with
the use of adding some materials like polypropylene, wheat husk fibre, copper slag etc. There
is a rapid increase in waste quantity of plastic fibres, if this waste can be utilize for stabilization
of soil than problem of solid waste can be resolve and also cost of soil stabilization can be
reduced. This study presented a review of literature on soil stabilization using polypropylene
and wheat husk fibre

14
 LITERATURE SUMMARY

The factors that affect the strength of reinforced soil are multifaceted and interrelated, involving
the properties of both the soil and the reinforcement material. One of the primary factors
influencing the strength of reinforced soil is the friction angle of the soil, which plays a crucial
role in determining the shear strength of the soil-reinforcement composite. The friction angle
is a measure of the soil's ability to resist shear stress, and it is influenced by factors such as the
soil's grain size distribution, moisture content, and density. A higher friction angle indicates a
stronger soil that is better able to resist deformation and failure. Another critical factor affecting
the strength of reinforced soil is the interaction between the soil and reinforcement, such as
friction or bonding. This interaction is essential in transferring loads from the soil to the
reinforcement, allowing the reinforcement to carry a portion of the applied load and thereby
increasing the overall strength of the reinforced soil. The strength of the reinforcement material
itself is also a key factor, as it directly affects the overall strength of the reinforced soil.
Different types of reinforcement materials, such as geogrids, geotextiles, and steel fibers, have
varying strengths and stiffnesses, and the selection of the appropriate reinforcement material
depends on the specific application and design requirements. While grain size distribution of
the soil influences its engineering properties, such as permeability and compressibility, it is not
a direct factor affecting the strength of reinforced soil. However, it can indirectly affect the
strength of the reinforced soil by influencing the friction angle and the interaction between the
soil and reinforcement.

15
 CHAPTER 3

EXPERIMENTAL INVESTIGATIONS

3.1 GENERAL

In the present study, we are conducting the experiment on the silty soil. The basic properties of
the soil will be found out and also the soil stabilized with the treated areca fibres will be tested
in the laboratory. The experimental works shall be carried out in different stages like carrying
out the basic properties on the soil like Sieve analysis, Atterberg limits, Compaction tests (light
and heavy compaction), California Bearing ratio (CBR), Unified Compression tests on soil
(UCS). This experiments will be carried out in this Phase 1 project.

16
 3.2 METHODOLOGY

Collection of soils

Conduc ng Basic test on soil

Grain Atterberg CBR UCS (Unified Compac on (IS

size limits (California compressive Light and
analysis Bearing ra o) strength of soil) heavy) test of
soil
r

UCS Procurement of sample

and fibre
CBR

Determina on of Index and

Freeze and thaw engineering proper es of soil with
treated fibres

Fa gue Test
Analysis
Plate load test
Results and
Compac on test Discussions

Fig No 3.1 : Methodology

3.3 MATERIALS USED

 Soils :
The soil used in this study was collected from, Ramanagar, Karnataka. In civil engineering
research, the study of red soil in Ramanagara is crucial for understanding its behaviour in
construction and geotechnical applications. The soil, characterized by good drainage and a
reddish colour due to iron oxide, often presents challenges due to its relatively low bearing
capacity and susceptibility to erosion. Researchers focus on enhancing its properties through

17
stabilization techniques such as lime or cement treatment to improve compaction, strength, and
load-bearing capacity for safe foundation design. Additionally, civil engineers investigate water
drainage systems and erosion control measures, especially in sloped areas, to prevent structural
damage. Understanding the soil's permeability and response to climate variations is vital for
designing durable infrastructure, ensuring long-term stability, and managing water resources
effectively in the region.

Fig No 3.2 : Soil collected from Ramanagara

3.3.1 SIEVE ANALYSIS OF SOILS
TABLE NO 3.1 : Test Results of Sieve Analysis of Soils
IS Sieve size(mm) Percentage Finer of Soils(%)
4.75 97.28
2.36 94.75
1.18 91.67
0.60 86.23
0.425 79.00
0.3 69.95
0.15 62.75
0.075 54.45
pan 44.32

18
 Particle Size Distribution
100
80 97.28
91.67 94.75

% passing
86.23
60 79
69.95
62.75
40 54.45
20
0
0.01 0.1 1 10

Sieve Size
(mm)

Grain Sieve Analysis curve

Areca nut Fibres :

The study of, areca fibres were collected from Tumkur district in the state of Karnataka, India.
Areca fibre consists of organic compounds such as cellulose, lignin, etc. Areca fibre shows
greater tensile strength when the fibres are treated with chemicals. Areca fibres extracted from
its cortex had variable lengths and diameters The dry areca nut shells, which are brown in
colour, were collected for the present work, and the fibre from the shell was extracted manually
in the laboratory. the physical appearance of areca nut fibre, and the physical properties of areca
nut fibre are tabulated in the given below table.

Fig No 3.3 : Areca nut fibres extracted from areca nut shell

19
 TABLE NO 3.2 Properties of Areca Fibres
Sl No Properties Value
1 Length (mm) 50
2 Diameter mm 1.5
3 L/D ratio 33.33
4 Young Modulus, (Mpa) 2770
5 Maximum Tensile Force (N) 3.21
6 Elongation at maximum tensile force (%) 2.4

7 Density, g/cc 1.12

 Treatement Areca Fibres: The areca fibre used in the study was chemically treated so
that its flexural strength and durability properties are improved. For the preliminary
treatment areca fibres collected from the site were kept for drying until the moisture
content in the areca fibres was completely reduced and became rather dry. The extracted
fibres were soaked in a 6% NaOH solution for 24 hours, and after 24 hours, the fibres
were washed with water and kept for drying for 1 day (24 hours) and then it can be used
for optimum content of the fibres which will be mixed with the soil.

Fig No 3.4 : Soaking of areca fibres treated in NaOH and dried

3.4 TESTS TO BE CONDUCTED ON SOILS

The tests which are to be conducted for the collected soil samples are

 Grain sieve analysis

 Atterberg limits – Liquid limit
Plastic limit

20
  Compaction test (IS Light and Heavy)
 California Bearing ratio (CBR)
 Unified Compressive Strength test on soils (UCS)
 Freeze and Thaw test on soil sample

3.4.1 Grain Sieve analysis of soil (IS: 2720 Part 4) - 1985

The Grain Sieve Analysis of Soil, as per IS 2720 Part 4 (1985), is a laboratory method used to
determine the particle size distribution (gradation) of a soil sample. This test is crucial for
classifying the soil and understanding its engineering properties. The procedure begins by air-
drying the soil sample, followed by sieving through a series of sieves with varying mesh sizes,
typically ranging from 4.75 mm down to 75 microns. The soil sample is weighed, and then
poured onto the largest sieve, with the sieves stacked in decreasing order of mesh size. The
sample is shaken to separate the soil particles, and after sieving, the mass of soil retained on
each sieve is weighed. The percentage of soil retained on each sieve is calculated by comparing
the mass retained to the total mass of the sample, from which the percentage passing each sieve
is derived. The results are plotted on a graph to create a particle size distribution curve, which
helps classify the soil according to systems like the Unified Soil Classification System (USCS).
This method is particularly used for coarse-grained soils, while finer soils, like clays and silts,
require a hydrometer test for accurate analysis.

1. Percentage Retained on Each Sieve:

Percentage Retained on Sieve= (Mass Retained on Sieve/Total mass of sample) ×100

Where:

Mass Retained on Sieve is the mass of the soil sample that remains on a specific sieve
after sieving.

Total Mass of Sample is the initial mass of the soil sample before the sieving process.

2. Percentage Passing Each Sieve:

Percentage Passing on Sieve= 100-percentage retained on sieve

3. Cumulative Percentage Passing (For plotting the gradation curve):

= ∑ ( Percentage Passing on Sieve/Total weight of soil)

21
 Fig No 3.5 : Soil retained on different sieve size

3.4.2 Atterberg limits

The Atterberg Limits are a set of tests used to determine the consistency and behaviour of fine-
grained soils (like clays and silts) as their water content varies. These limits help classify the
soil and assess its engineering properties, particularly its ability to shrink or swell. The
Atterberg Limits consist of three primary tests: Liquid Limit (LL), Plastic Limit (PL), and
Shrinkage Limit (SL).

 Liquid Limit : The Liquid Limit (LL) is the water content at which a soil changes from
a liquid state (flowing) to a plastic state (deformable). It is determined using the
Casagrande apparatus, which is a device used to measure the soil's flow ability. The test
involves making a groove in a soil sample and then repeatedly dropping the apparatus
from a specific height until the groove closes over a specified distance. The water
content at which this occurs is the liquid limit.

The Liquid Limit is expressed as a percentage by weight, calculated as:

LL= W2/W1×100
Where:
 W1 is the mass of the wet soil at the time of testing.
 W2 is the mass of the dry soil.

22
 Fig No 3.6 : Liquid limit test on soil

 Plastic Limit (PL)

The Plastic Limit (PL) is the water content at which a soil transitions from a plastic state
(malleable) to a semi-solid state. In this state, the soil can be rolled into threads without
crumbling. The plastic limit is determined by rolling a soil sample into a thread until it crumbles
at a specified diameter (usually 3 mm).
Similar to the Liquid Limit, the Plastic Limit is expressed as a percentage:
PL=(W3/W4)*100
Where:
 W3 is the mass of the wet soil at the time of testing.
 W4 is the mass of the dry soil.

3.4.3 Compaction Test on Soils (IS: 2720 Part 7)

The compaction test is one of the most important soil tests, used to determine the maximum
dry density and optimum moisture content of a soil sample. It helps understand the soil’s ability
to compact under various moisture conditions, which is critical for designing foundations,
embankments, pavements, and other civil engineering structures. The compaction test is
typically carried out using two methods: Standard Proctor Test and Modified Proctor Test. Both
methods are based on the principle of compacting a soil sample in a mould to a certain degree
under a standard compaction energy and then measuring the resulting dry density at different
moisture contents.
 IS Light Compaction of soils (Standard Proctor test) (IS: 2720 Part 7): Light
compaction, as determined by the Standard Proctor Test (IS: 2720 Part 7), involves
23
 applying a relatively low compaction energy. It uses a 2.5 kg rammer dropped from a
height of 30 cm, with 25 blows per layer over three layers of soil. By conducting this
test we could able to find the Optimum moisture content (OMC) and Maximum dry
density (MDD) of the soil.

Fig No 3.6 : IS Light Compaction of soils (Standard Proctor test)

 Heavy Compaction of soil (Modified Proctor test) (IS: 2720 Part 8) : Heavy
compaction, defined by the Modified Proctor Test (IS: 2720 Part 8), involves
significantly higher compaction energy. In this test, a 4.5 kg rammer is dropped from a
height of 45 cm, with 56 blows per layer across five layers. By conducting this test we
could able to find the Optimum moisture content (OMC) and Maximum dry density
(MDD) of the soil. both light compaction (Standard Proctor Test) and heavy compaction
(Modified Proctor Test), the main objective is to determine the maximum dry density
(MDD) and the optimum moisture content (OMC) of a soil. To calculate these, the
following formulas are used:
The dry density of the soil is calculated after determining its wet weight and moisture content.
The formula for dry density ρd
ρd=Weight of Dry Soil/Volume of the mould
Where:
 Weight of Dry Soil = Wet weight of soil – Moisture content
 Volume of Mold = Known constant volume of the compaction mould

The moisture content (w) is determined by the formula:

24
 w=Weight of Water/Weight of Dry Soil× 100
Where:
 Weight of Water is the difference between the wet and dry weights of the soil sample.
 Weight of Dry Soil is the dry weight of the soil after oven drying.

3.4.4 California Bearing Ratio (CBR) IS 2720 Part 16: 1987

The California Bearing Ratio (CBR) test is a crucial method used to assess the strength of soil,
primarily for pavement design and road construction. It measures the resistance of a soil sample
to penetration by a plunger under controlled conditions, simulating the behaviour of the soil
under load. The test involves compacting a soil sample into a cylindrical mould and applying
a load through a plunger to penetrate the soil at a constant rate. The load required to achieve
specific penetrations (usually at 2.5 mm and 5.0 mm) is recorded and compared to standard
values for a reference material, such as crushed stone, to calculate the CBR value.

The California Bearing Ratio (CBR) is calculated using the following formula:
CBR = (Load on soil at penetration/Standard Load at same penetration)* 100

Where:

 Load on Soil at Penetration is the load required to achieve a specific penetration of the soil
sample, typically at 2.5 mm and 5.0 mm of penetration.

 Standard Load at Same Penetration is the load required to achieve the same penetration on
a standard material.

Fig No 3.8 : CBR test on soil

25
3.4.5 Unified Compressive Strength of soil (UCS) (IS 2720 Part 10: 1991) : The Unconfined
Compressive Strength (UCS) test, as per IS 2720 Part 10: 1991, is a standard laboratory
procedure used to measure the compressive strength of cohesive soils, such as clays and silts.
This test involves applying a compressive axial load to a cylindrical soil sample, which is
unconfined and typically compacted to a specified density. The load is applied at a constant
rate of strain, and the sample is monitored until it fails, usually by cracking or shearing. The
test measures the maximum load at which failure occurs, and the Unconfined Compressive
Strength (UCS) is calculated by dividing this maximum load by the cross-sectional area of the
sample.

The Unconfined Compressive28 Strength (UCS) is calculated using the following formula:

UCS=Maximum Load at Failure (P)/Cross Sectional area of the sample

Where:

 P = Maximum axial load at failure (measured in Newtons or kg)

 A = Cross-sectional area of the soil sample (measured in square mm or square cm)

Since the sample is cylindrical, the area is calculated as:

A=πd2/4
Where:
 d = Diameter of the soil sample

Fig No 3.9 : UCS test on soil alone

26
3.4.6 Freeze and Thaw test on soil sample IS : 4332 (Part 4) - 1968

Durability is defined as the ability of a material to retain stability and integrity over years of
exposure to the destructive forces of weathering and hence it is one of the most important
factors for any stabilized soil [20]. A good stabilizer should help, not only in gaining the
strength, but also to retain its bonding with soil during the seasonal changes. Hence, checking
durability is vital before recommending any stabilizer for practical applications. For the present
study, the procedures as per IS : 4332 (Part 4) – 1968 were adopted. Soil specimens with
200mm height and 100mm diameter were prepared and then they were subjected to 7 days
moist curing. The total of 8 specimens are to be prepared to conduct the test . The prepared
specimens to be subjected to freezing and thawing .Out of 8 specimens 2 specimens should be
tested for 3cycles and 2 specimens for 7 cycles and 2 specimens should be tested for

27
 CHAPTER 4

EXPERIMENTAL ANALYSIS

4.1 Test Results

4.1.1 Grain Sieve Analysis

TABLE NO 4.1 : Grain sieve analysis

Sieve size Weight Cummulative % Weight % finer

Retained, g weight retained retained %
g
4.75 16.30 2.72 2.72 97.28
2.36 15.20 2.53 5.25 94.75
1.18 18.50 3.08 3.08 91.67
0.6 32.60 5.43 13.77 86.23
0.425 43.40 7.23 21.00 79.00
0.3 54.30 9.05 30.05 69.95
0.15 43.20 7.20 37.25 62.75
0.075 49.80 8.30 45.55 54.45
pan 60.80 10.13 55.68 44.32

 Gravel =2.72
 Sand = 42.83
 Silt and clay = 54.45
 And the soil is classified as low compressible clayey soil (CL)

28
 Particle Size Distribution
100
90 97.28
94.75
80 91.67
86.23
70 79
% passing

60 69.95
62.75
50
54.45
40
30
20
10
0
0.01 0.1 1 10

Sieve Size
(mm)

Particle Size Distribution of Soil

4.1.2 Atterberg Limit

 Liquid Limit

TABLE NO 4.2 : Liquid limit test of soil

Determination 1 2 3 4 5 6
No
No of Blows 34 33 32 29 23 18
Moisture
container no
Wt of 11.20 11.10 14.0 12.40 11.30 10.90 11.50 17.20 12.50 14.0 11.40 11.10
container “g”
Wt of 13.70 13.10 15.60 14.80 13.10 12.00 13.50 19.70 15.10 16.60 14.90 12.60
container +
wet soil “g”
Wt of 13.55 12.65 15.30 14.50 12.60 11.90 13.00 19.10 14.30 16.00 13.80 12.00
container +

29
oven dry soil
“g”
Weight of 0.15 0.45 0.30 0.30 0.50 0.10 0.50 0.60 0.80 0.60 1.10 0.60
water “g”
Weight of dry 2.35 1.55 1.30 2.10 1.30 1.00 1.50 1.90 1.80 1.90 2.40 0.90
soil ‘g’
Water content 6.4 29.0 23.1 14.3 38.5 10.0 33.3 31.6 44.4 31.6 45.8 66.7
%
Average 17.71 18.68 24.23 32.46 38.01 56.25

Liquid limit of the soil sample = 38.01 %

60.00

50.00
Moisture content

40.00

30.00
LIQUID LIMIT
20.00 Linear (LIQUID LIMIT)

10.00

0.00
0 10 20 30 40
No of blows

Liquid Limit

30
  Plastic Limit
TABLE NO 4.3 : Plastic limit of soil

Determination No 1 2 3 4
Moisture container no.
Wt of container "g" 10.57 14.65 10.15 11.3
Wt of container + wet soil "g" 13.14 17 13.22 14.2
Wt of container + oven dry soil
"g" 12.8 16.65 12.8 13.8
Weight of water "g" 0.34 0.35 0.42 0.4
Wt of dry soil 'g' 2.23 2 2.65 2.5
water content % 15.24663677 17.5 15.849057 16

 The Plastic limit of the soil sample is 16.148%

 Plasticity Index = Liquid limit – Plastic limit

= 21.862

31
4.1.3 California Bearing Ratio (CBR)

 Soaked Condition
Area of Plunger = 19.635 cm2

TABLE NO 4.4 : CBR Test on soils for Soaked Condition

Sl no Penetration Proving ring dial Load on Plunger Unit load
mm Reading in kg Kg/cm2
1 0 0 0 0
2 0.5 3 15.2 0.77
3 1 5 17 0.86
4 1.5 6 24.3 1.23
5 2 8 32.3 1.64
6 2.5 10 48.2 2.45
7 3 12 53.2 2.70
8 4 15 62.8 3.19
9 5 23 70.5 3.59
10 7.5 27 142 7.23
11 10 32 202.5 10.31
12 12.5 36 217.8 11.09
CBR value (at 2.5mm), %=2.454+/70*100 3.505
CBR Value (at 5mm), %=3.590/105*100 3.419

12

10
Unit load kg/cm2

0
0 2 4 6 8 10 12 14
Penetration mm

Series1

32
 Unsoaked condition
Area of Plunger = 19.635cm2
Sl no Penetration Proving ring dial Load on Plunger Unit load
mm Reading in kg Kg/cm2
1 0 0 0 0
2 0.5 2.75 23 1.171
3 1 5.75 42.2 2.149
4 1.5 7.75 50 2.546
5 2 11 75.8 3.860
6 2.5 15.25 103 5.245
7 3 18.5 119.3 6.075
8 4 20 133.4 6.793
9 5 22.5 149.4 7.608
10 7.5 27.2 181.4 9.238
11 10 30.5 200.6 10.216
12 12.5 34.5 266.7 13.582
CBR value (at 2.5mm), %=5.245+/70*100 7.493
CBR Value (at 5mm), %=7.608/105*100 7.246

TABLE NO 4.5 : CBR Test on soils for Unsoaked Condition

16
14
12
Unit load kg/cm

10
8
6 Series1

4
2
0
0 5 10 15
Penetration , mm

33
 4.1.4 Compaction test of soil

 Modified proctor test for soil alone

TABLE NO 4.6 : Modified proctor (IS Heavy compaction) test for soil

trial no 1 2 3 4 5
weight of mould 5110 5110 5110 5110 5110
Weight of mould +
compacted soil 7140 7190 7230 7195 7090
weight of compacted soil
Wg 2030 2080 2120 2085 1980
wet density 2.03 2.08 2.12 2.085 1.98
cup no. 70 45 53 8 10
W1 empty wt of
container 11.1 8.9 11.4 11.6 11.3 11.1 11.5 10.9 11.4 8.9
W2 container + wet soil 16.2 17 15.3 16.2 15.7 15.4 16.5 22.1 19.1 22.4
W3 container + dry soil 15.6 16.1 14.9 15.5 15.2 14.7 15.8 20.1 17.5 20.5
Wet density g/cc 13.33 12.5 11.43 17.95 12.82 19.44 16.28 21.74 26.23 16.38
Moisture content % 12.92 14.69 16.13 19.01 21.30
Dry density 1.798 1.81 1.83 1.75 1.63

 Optimum moisture content in % = 1.83

 Maximum dry density in g/cc = 16.13

34
 1.850

1.800

1.750
Dry density

1.700

1.650

1.600

1.550

1.500
12.92 14.69 16.13 19.01 21.30
Moisture content

 Standard proctor test for soil alone

TABLE NO 4.6 : Standard proctor (IS Light compaction) test for soil

trial no 1 3 4 5
Weight of mould 5110 5110 5110 5110 5110
Weight of mould +
compacted soil 6850 6890 6950 6920 6890
Weight of compacted soil
Wg 1740 1780 1840 1810 1780
wet density 1.69 1.78 1.85 1.81 1.63
cup no. 70 45 53 8 10
W1 empty wt of container 10.5 9.6 10.2 9.7 11.8 11.3 11.3 10.65 10.7 10.2
W2 container + wet soil 15.7 16.5 15.1 16 16 15.1 15.7 15.9 15.7 15.3
W3 container + dry soil 15.2 15.9 14.7 15.2 15.5 14.6 15.2 15.2 15.2 15
Wet Density g/cc 10.64 9.52381 8.89 14.55 13.51 15.15 12.82 15.38 11.11 6.25
Moisture content % 10.08 11.72 14.33 14.10 8.68
Dry density in g/cc 1.535 1.59 1.62 1.59 1.50

 Optimum moisture content in % = 1.62

 Maximum dry density in g/cc = 14.33

35
 Chart Title
1.640
1.620
1.600
1.580
1.560
1.540
1.520
1.500
1.480
1.460
1.440
10.08 11.72 14.33 14.10 8.68

4.1.5 Unified Compressive strength test on soils

 Length = 195mm
 Diameter = 100mm
 Cross sectional area = 7854
TABLE NO 4.7 : Unified Compressive strength test of soil

Load Deformation Corrected

kg (mm)∆L Strain€ area Stress kg/cm2 kn/m2
P=
Div DivXPRC Div ∆L=DIVXLC (%)∆L/L AC=Ao/1-€ P/AC
0 0 0 0 0 7854 0 0 0
0.8 5.12 50 0.5 0.25641 7874.19023 6.37653 0.065023 6.376558
1.6 10.24 100 1 0.512821 7894.48454 12.7203 0.129711 12.72033
2.9 18.56 150 1.5 0.769231 7914.88372 22.9961 0.234496 22.99618
3.8 24.32 200 2 1.025641 7935.38860 30.055 0.306476 30.05506
4.8 30.72 250 2.5 1.282051 7956.00000 37.8658 0.386125 37.86594
5.6 35.84 300 3 1.538462 7976.71875 44.062 0.449309 44.06218
6.3 40.32 350 3.5 1.794872 7997.54569 49.4407 0.504157 49.44087
7.1 45.44 400 4 2.051282 8018.48168 55.5734 0.566693 55.57359

36
8.5 54.4 450 4.5 2.307692 8039.527559 66.3574 0.676659 66.3576
8.9 56.96 500 5 2.564103 8060.684211 69.2977 0.706642 69.29795
9.2 58.88 550 5.5 2.820513 8081.952507 71.4451 0.72854 71.44532
8.8 56.32 600 6 3.076923 8103.333333 68.1584 0.695025 68.15869
8.8 56.32 650 6.5 3.333333 8124.827586 67.9781 0.693187 67.97838

4.1.6 Unified Compressive strength test of soil mixed fibre

 Length = 195mm
 Diameter = 100mm
 Cross sectional area = 7854mm

UCS test is conducted to determine the optimum percentage of fibre and optimum molarity of
NaOH mixed with fibre.

TABLE NO 4.8: Unified Compressive strength test of soil mixed Areca fibre

NaOH
0.5M 1.61 1.81 4.51 3.52
1.0M 1.76 2.01 4.39 4.25
1.5M 1.89 2.11 4.68 4.27
2M 2 2.54 4.4 3.78
Fibers 0.25% 0.50% 0.75% 1%

 This is the peak factor we have obtained for the 0.75% of Areca fibre mixed with 1.5M
of NaOH
 The peak factor will be considered as optimum fibre content mixed with the soil
 The peak factor will be represented in Kg/cm2

37
  And the optimum fibre content of 0.75% of fibres should be mixed with soil to carry
out the further experiment.
 Compared to other percentage of fibres and molarity of NaOH the peak factor will be
obtained in 1.5M of NaOH with 0.75% fibre content

5
4.5
4
3.5
NaOH molarity

3 0.25%
2.5 0.5
2 0.75%
1.5 1.00%
1
0.5
0
Fibre percentage

Optimum fibre content obtained by treating Areca fibres with NaOH

TABLE NO 4.9 : UCS test on soil mixed with 1.5M of NaOH with 0.75% areca fibres

38
 Corrected
load Deformation Strain area Stress kg/cm2 kn/m2
P=Div*prc Div dl=Div*xlc (%)dl/l AC=Ao/1-e P/AC
0 0 0 0 0 7854 0 0 0
2.5 16 50 0.5 0.25252525 7834.166667 20.0284736 0.204234351 20.02855
4.2 26.88 100 1 0.50505051 7814.333333 33.7332362 0.343984556 33.73336
5.7 36.48 150 1.5 0.75757576 7794.5 45.8973112 0.468024062 45.89748
7.9 50.56 200 2 1.01010101 7774.666667 63.7743385 0.650319685 63.77458
10.1 64.64 250 2.5 1.26262626 7754.833333 81.7428085 0.833547767 81.74311
12.3 78.72 300 3 1.51515152 7735 99.8034244 1.01771548 99.8038
14.6 93.44 350 3.5 1.76767677 7715.166667 118.770393 1.21112545 118.7708
17.1 109.44 400 4 2.02020202 7695.333333 139.466314 1.422165898 139.4668
18.6 119.04 450 4.5 2.27272727 7675.5 152.092192 1.550914495 152.0928
20.6 131.84 500 5 2.52525253 7655.666667 168.88258 1.722129442 168.8832
21.7 138.88 550 5.5 2.77777778 7635.833333 178.362661 1.818799726 178.3633
22.9 146.56 600 6 3.03030303 7616 188.716206 1.924376895 188.7169
25.7 164.48 650 6.5 3.28282828 7596.166667 212.343655 2.165310716 212.3444
27.9 178.56 700 7 3.53535354 7576.333333 231.124391 2.356821635 231.1252
30.2 193.28 750 7.5 3.78787879 7556.5 250.83429 2.557807421 250.8352
32.3 206.72 800 8 4.04040404 7536.666667 268.9824 2.742867329 268.9834
34.5 220.8 850 8.5 4.29292929 7516.833333 288.061239 2.937418062 288.0623
36.7 234.88 900 9 4.54545455 7497 307.241023 3.132998163 307.2422
38.7 247.68 950 9.5 4.7979798 7477.166667 324.843778 3.312496977 324.845
40.8 261.12 1000 10 5.05050505 7457.333333 343.381787 3.501532761 343.3831
42.8 273.92 1050 10.5 5.3030303 7437.5 361.174799 3.682971661 361.1761
43.6 279.04 1100 11 5.55555556 7417.666667 368.909489 3.761843836 368.9109
45.1 288.64 1150 11.5 5.80808081 7397.833333 382.624389 3.901697415 382.6258
47.3 302.72 1200 12 6.06060606 7378 402.367727 4.103024183 402.3692
49.6 317.44 1250 12.5 6.31313131 7358.166667 423.070463 4.314134122 423.072
51.8 331.52 1300 13 6.56565657 7338.333333 443.029835 4.517663836 443.0315
53.6 343.04 1350 13.5 6.81818182 7318.5 459.667038 4.687316718 459.6687
52.8 337.92 1400 14 7.07070707 7298.666667 454.036788 4.629903932 454.0385
52.8 337.92 1450 14.5 7.32323232 7278.833333 455.273945 4.642519474 455.2756

39
Fig No 4.1 : UCS test mould to determine the optium fibres and optimum molarity of
NaOH

UCS test on soil mixed with 1.5M of NaOH with 0.75% areca fibres

1.5 0.75%
500

400

300
Stress

200
1.5 0.75%
100

0
0 2 4 6 8
Strain

40
TABLE NO 4.10 : Unified Compressive strength test of soil mixed with Polypropylene
fibre

Molarity Concentration of
Sl No. % of PPF UCS value in kg/cm2
NaOH
1 0.5 3.1
2 1 3.4
0.5
3 1.5 3.8
4 2 3.5
1 0.5 3.2
2 1 3.5
1
3 1.5 3.3
4 2 3.6
1 0.5 2.9
2 1 3
1.5
3 1.5 3.2
4 2 3.1
1 0.5 3.3
2 1 3.5
2
3 1.5 3.6
4 2 3.7

5
UCS For Varying Molarity of NaOH and PPF percentage
3.8 3.7
4 3.5 3.6 3.5 3.6
3.3 3.4 3.5 3.3 3.2
3.1 3.2 2.9 3 3.1
3
UCS (kg/cm2)

0
0.5 1 1.5 2
0.5M_NaOH 3.1 3.4 3.8 3.5
1M_NaOH 3.2 3.5 3.3 3.6
1.5M_NaOH 2.9 3 3.2 3.1
2M_NaOH 3.3 3.5 PPF(%) 3.6 3.7

Optimum fibre content of Polypropylene fibres

41
4.1.7 Durability test on soils

TABLE NO 4.10 : Freeze and thaw test on soil mixed without fibres

Specimen Test Weight of Percentage Average UCS Average

number cycle specimen in kg loss in percentage value in UCS
weight loss in KN/m2 value in
Initial Final
weight KN/m2
1 3 2.954 2.755 6.736 6.781 90.85 90.16
2 2.93 2.73 6.825 89.47
3 6 2.955 2.75 6.937 7.040 85.42 85.085
4 2.94 2.73 7.142 84.75
5 9 2.95 2.685 8.983 9.584 78.53 77.88
6 2.945 2.645 10.181 77.23
7 12 2.95 2.585 12.372 12.819 67.29 66.93
8 2.94 2.55 13.265 66.57

Percentage loss in weight v/s Test cycles (days) for soil alone

14 12.81909374
12
9.584904032
Percentage loss in weight %

10

8 6.781283434 7.040125695

0
3 6 9 12
Test cycles (Days)

Series1

42
 UCS value in KN/m2 v/s Test cycles (days) for soil alone

Chart Title
90.16
85.085
77.88
66.93
UCS valu in KN/m

3 6 9 12
Test cycles (Days)

TABLE NO 4.11 : Freeze and thaw test on soil mixed with Areca nut fibres

Specimen Test Weight of Percentage Average UCS Average

number cycle specimen in kg loss in percentage value in UCS
weight loss in KN/m2 value in
Initial Final
weight KN/m2
1 3 3.18 3.100 2.515 3.187 106.3 103.90
2 3.162 3.040 3.858 101.5
3 6 3.152 3.000 4.822 5.194 98.53 95.885
4 3.198 3.020 5.565 93.24
5 9 3.214 2.995 6.813 7.205 85.67 83.295
6 3.225 2.980 8.527 80.92
7 12 3.220 2.958 8.136 9.159 74.32 72.27
8 3.290 2.955 10.182 70.22

43
 Percentage loss in weight v/s Test cycles (days) for Areca nut fibres

freeze and thaw cycles

Percentage loss in weight %
9.159508392

7.205419121

5.194156881

3.187020395

3 6 9 12
Test cycles (Days)

UCS value in KN/m2 v/s Test cycles (days) for Areca nut fibres

Chart Title
Series1

103.9
95.885
UCS value in KN/m2

83.295
72.27

3 6 9 12
Test cycles (Days)

44
 TABLE NO 4.12 : Freeze and thaw test on soil mixed with Polypropylene fibres

Specimen Test Weight of Percentage Average UCS Average

number cycle specimen in kg loss in percentage value in UCS
weight loss in KN/m2 value in
Initial Final
weight KN/m2
1 3 3.22 3.100 3.726 4.307 120.6 116.9
2 3.212 3.055 4.887 113.2
3 6 3.211 3.025 5.792 6.152 105.6 100.1
4 3.225 3.015 6.511 94.6
5 9 3.211 2.988 6.944 7.208 85.45 82.4
6 3.225 2.984 7.472 79.35
7 12 3.220 2.958 8.136 8.254 72.45 70.425
8 3.225 2.955 8.372 68.40

Percentage loss in weight v/s Test cycles (days) for Polypropylene fibres

Freeze and thaw of polypropylene fibres

8.254369493
Percentage loss in weight %

7.208872601
6.152107943

4.307314187

3 6 9 12
Test cycles(Days)

45
 UCS value in KN/m2 v/s Test cycles (days) for Polypropylene fibres

UCS for Freeze and thaw cycle

140

120
Average UCS value

100

80

60

40

20

0
3 6 9 12
Test cycles (Days)

46
 TABLE NO 4.13 : Physical Properties of soil

Colour RED
Particle size distribution IS 2720 Part 4
Gravel 2.72
Sand 42.83
Silt and clay 54.45
Atterberg limits IS 2720 Part 5
Liquid limit , % 38.01
Plastic limit % 16.14
Plasticity index % 21.86
Soil classification IS 2720 Part 4 CL
Standard compaction test IS 2720 Part 7
Optimum moisture content % 1.83
Maximum dry density g/cc 16.13
CBR% (Soaked) IS 2720 Part 16 3.149
CBR % (UNSOAKED) 3.696
UCS (Unified compressive strength of soil), KN/m2 IS 2720 Part 10 71.44
UCS (Unified compressive strength of soil) test treated Areca IS 2720 Part 10 459.67
fibres , KN/m2
UCS (Unified compressive strength of soil) test treated IS 2720 Part 10 380
Polypropylene fibres , KN/m2
Freeze and Thaw test for soil alone IS 4332 Part 4
Percentage loss in weight, % (peak value) 12.819
UCS value in KN/m2 (Peak value) 90.16
Freeze and thaw test for optimum content of Areca nut fibre IS 4332 Part 4
mixed with soil
Percentage loss in weight, % (peak value) 9.159
UCS value in KN/m2 (Peak value) 103.90
Freeze and thaw test for optimum content of Polypropylene IS 4332 Part 4
fibre mixed with soil
Percentage loss in weight, % (peak value) 8.254
UCS value in KN/m2 (Peak value) 116.9

47
 CHAPTER 5

DISCUSSION AND CONCLUSION

5.1 BASIC PROPERTIES OF SOIL

• The engineering properties of soil was determined and the soil were determined gravel
2.72% , sand 42.83%, and silt and clay 54.45% and was classified as inorganic clay of low
plasticity (CL).

• Liquid limit of the soil is 38.01%, plastic limit is 16.14%. Hence plasticity index of the
soil sample is 21.87%

• Maximum dry density of the soil is 1.83g/cc at optimum moisture content of 16.13%.

• The CBR value of untreated soil was found to be 3.419 and 7.493% for soaked and
unsoaked conditions respectively.

5.2 OPTIMUM PERCENTAGE OF NaOH SOLUTION’S MOLARITY AND ARECA

NUT FIBRE CONTENT

• The areca nut fibre treated with 0.5M, 1.0M, 1.5M, 2.0 Molarity of NaOH solution.

• The areca nut fibre content of 0.25%, 0.5%, 0.75%, 1.0% by weight of soil to determine
the optimum percentage by conducting Unconfined compressive strength test was found to be
1.61,1.76, 1.89, 2 kg/cm2 for 0.25% , 1.81, 2.01, 2.11, 2.54 kg/cm2 for 0.50%, 4.51, 4.39, 4.68,
4.4 kg/cm2 for 0.75%

and 3.52, 4.25, 4.27, 3.78 for 1.0% fibre content respectively. The optimum percentage was
found to be 0.75% of fibre content treated with 1.5M sodium hydroxide solution.

• The CBR test was conducted for untreated and soil mixed with optimum percentage of
treated areca nut fibres in soaked and unsoaked conditions. The CBR values was found to be
3.149 and 3.696% for untreated soil and 14.98% for soil stabilized with treated areca nut fibres
respectively.

5.3 OPTIMUM PERCENTAGE OF NaOH SOLUTION’S MOLARITY AND

POLYPROPYLENE FIBRE CONTENT

 The Polypropylene fibre treated with 0.5M, 1.0M, 1.5M, 2.0 Molarity of NaOH solution.

48
The Polypropylene fibre content of 0.5%, 1.0%, 1.5%, 2.0% by weight of soil to determine the
optimum percentage by conducting Unconfined compressive strength test was found to be 3.1,
3.4, 3.8 , 3.5 kg/cm2 for 0.5% , 3.2,3.5,3.3,3.6kg/cm2 for 1.0%, 2.9,3.0,3.2,3.1 kg/cm2 for
1.5% and 3.3, 3.5, 3.6, 3.7 for 2.0% fibre content respectively. The optimum percentage was
found to be 1.5% of fibre content treated with 0.5M sodium hydroxide solution.

5.4 EFFECT OF TREATED ARECA NUT FIBRE AND POLYPROPYLENE FIBRE ON

STABILIZATION WITH SOIL ON CHARACTERISTICS OF FREEZING AND
THAWING

 The percentage weight loss of red soil alone varies for different freezing and thawing cycles
3, 6, 9, 12. The percentage weight loss of red soil for 3, 6, 9, 12 cycles of freezing and
thawing is 6.781, 7.04, 9.58, 12.81. when soil is stabilized with treated areca nut fibre the
percentage weight loss of soil will be comparatively reduced. The percentage weight loss
of soil will be 3.18, 5.19, 7.20, 9.15. when soil is stabilized with treated propylene fibre the
percentage weight loss of soil will be comparatively reduced. The percentage weight loss
of soil will be 4.30, 6.15, 7.20, 8.25.

 The UCS values of red soil for alone varies for different freezing and thawing test cycles
3, 6, 9, 12 cycles are 90.16, 85.085, 77.88, 66.93 KN/m2 respectively when soil is stabilised
with treated areca nut fibre the UCS value of soil comparatively increased. The UCS values
for 3, 6, 9, 12 cycles are 103.90, 95.88, 83.29, 72.27KN/m2 respectively. when soil is
stabilised with treated Polypropylene fibre the UCS value of soil comparatively increased.
The UCS values for 3, 6, 9, 12 cycles are 116.9, 100.1, 82.4, 70.42 KN/m2 respectively

5.5 CONCLUSION
• The engineering properties of soil was determined and the soil was classified as
inorganic clay of low plasticity (CL)
• The optimum was determined by conducting unconfined compressive strength test for
varying percentage of treated fibres which was found to be 0.75% of fibre content treated with
1.5M of sodium hydroxide solution.
• By conducting California bearing ratio test it was found that the stabilized soil offer
more resistance compared to untreated soil.
 The percentage loss in weight during freezing and thawing cycles is observed to be less in
case of soil stabilized with treated fibres as compared to untreated soil.

49
 CHAPTER 6

REFERENCE

 Yowa Yaniam Ajanta Kalita, Kunchok Tashi1and Tadgi “A review on Comparative study
of using Silica Fume and Areca Fiber on Soil Stabilization “ ICES2024 IOP Conf. Series:
Earth and Environmental Science 1365 (2024) 012002 IOP Publishing doi:10.1088/1755-
1315/1365/1/012002 (2001)

 Lekha B M , S Goutham1 “Evaluation of lateritic soil stabilized with Areca nut coir for low
volume pavements” B.M. Lekha, S. Goutham, A.U.R. Shankar, Evaluation of Lateritic Soil
Stabilized with Arecanut Coir for Low Volume Pavements (2014), doi:
http://dx.doi.org/10.1016/j.trgeo.2014.09.001

 Chethan B A , A. U. Ravi Shankar “Alkali Activated Black Cotton Soil with Partial
Replacement of Class F Fly Ash and Areca Nut Fiber Reinforcement” M. S. Ranadive et al.
(eds.), Recent Trends in Construction Technology and Management, Lecture Notes in Civil
Engineering 260 , https://doi.org/10.1007/978-981-19-2145-2_88

 Ravi Diamond and Renjitha Mary Varghese “Desiccation Cracking Behaviour and Strength
Characteristics of Areca Fiber Reinforced Fine Grained Soils “C. N. V. Satyanarayana
Reddy et al. (eds.), Ground Improvement and Reinforced Soil Structures,
https://doi.org/10.1007/978-981- 16-1831- 4_10

 Sooraj P. Sudhakaran1; Anil Kumar Sharma, Ph.D., A.M.ASCE2; and Sreevalsa

Kolathayar, Ph.D.3 “Soil Stabilization Using Bottom Ash and Areca Fiber: Experimental
Investigations and Reliability Analysis” © 2018 American Society of Civil Engineers. DOI:
10.1061/(ASCE)MT.1943-5533.0002326.

 Sreevalsa Kolathayar , Swetha Prasannan, and Anil Kumar Sharma “Strength Tests and
Model Experiments on Soil Reinforced with Areca and PVA Fibers” © Springer Nature
Singapore Pte Ltd. 2020 M. Latha Gali and R. R. P. (eds.), Geotechnical Characterization
and Modelling, https://doi.org/10.1007/978-981- 15-6086- 6_1214

50
 Swetha Prasannan, , Sreevalsa Kolathayar,, Anil Kumar Sharma "Comparative Study on
Bearing Capacity of Bottom Ash–Stabilized Soil Mixed with Natural and Synthetic
Fibers “ https://doi.org/10.1520/ACEM20190031

 Kiran, Harsha S ”Experimental Study on Stabilization of Black Cotton Soil with Molasses
and Areca nut Fibers” International Journal of Applied Engineering Research ISSN 0973-
4562 Volume 13, Number 7 (2018) pp. 219-223 http://www.ripublication.com

 Jyotesh Kumar Choudhary1, Udai Kumar Singh2 & Ranjeet Kumar Singh3 “STUDY ON
STABILIZATION OF SOIL USING POLYPROPYLENE FIBER WASTE” International
Research Journal of Engineering and Technology (IRJET) Volume: 09 Issue: 01 | Jan 2022

 Shish Pal1 , Vinod Kumar Sonthwal2 , Jasvir S Rattan3 “Review on Stabilisation of Soil
Using Polypropylene as Waste Fibre” International Journal of Innovative Research in
Science, Engineering and Technology Vol. 4, Issue 11, November 2015

 Muttana S. Balreddy1 ,Sanjay S. Sajjan1” Utilization of alkali‑treated areca fibers for

stabilizing silty sand soil for use in pavement subgrades: Analysis using IITPAVE software”
Emergent Materials (2024) 7:1927–1939 https://doi.org/10.1007/s42247-024-00710-4

 Muhammad Ali1a, Mubashir Aziz2b , Muhammad Hamza1c and Muhammad Faizan

Madni3d “Engineering properties of expansive soil treated with polypropylene fibers”
Geomechanics and Engineering, Vol. 22, No. 3 (2020) 227-236 DOI:
https://doi.org/10.12989/gae.2020.22.3.227

 Muttana S. Balreddy1 · Sanjay S. Sajjan1 “Utilization of alkali treated areca fbers for
stabilizing silty sand soil for use in pavement subgrades Analysis using IITPAVE software”
Emergent Materials (2024) https://doi.org/10.1007/s42247-024-00710-4

 Chethan B A , A. U. Ravi Shankar ” Alkali Activated Black Cotton Soil with Partial
Replacement of Class F Fly Ash and Areca Nut Fiber Reinforcement” M. S. Ranadive et al.

51
 (eds.), Recent Trends in Construction Technology and Management, Lecture Notes in Civil
Engineering 260, https://doi.org/10.1007/978-981-19-2145-2_88

 Rao Asha Uday,1 Dhanalakshmi Kiran,1 Arun Kumar G S,2 Prakash K G1 and
Balakrishna S Maddodi1,“Effect of Polypropylene Macro Fiber on Geotechnical
Characteristics of Black Cotton Soil: An Experimental Investigation and Correlation
Analysis” Engineered Science DOI: https://dx.doi.org/10.30919/es8d775

 Ping Jiang 1,2,* , Lin Zhou 2, Weiqing Zhang 2, Wei Wang 2 and Na Li 2 “Unconfined
Compressive Strength and Splitting Tensile Strength of Lime Soil Modified by Nano Clay
and Polypropylene Fiber” Crystals 2022, 12, 285. https://doi.org/10.3390/cryst12020285

 Jia Liu 1 , Xi’an Li 1,*, Gang Li 2 and Jinli Zhang 3 “Investigation of the Mechanical
Behavior of Polypropylene Fiber-Reinforced Red Clay” Appl. Sci. 2021, 11, 10521.
https://doi.org/10.3390/app112210521

52