EFFECT OF COMPACTION ENERGY ON ENGINEERING

CHARACTERISTIC OF COMPACTED SOIL

Muhammad Ikram Bin Uzir Abdul Wahab

Bachelor of Engineering with Honours

(Civil Engineering)

2010

Faculty of Engineering

UNIVERSITI MALAYSIA SARAWAK

BORANG PENGESAHAN STATUS TESIS *

JUDUL: EFFECT OF COMPACTION ENERGY ON ENGINEERING CHARACTERISTIC OF

COMPACTED SOIL

SESI PENGAJIAN: 2009 / 2010

Saya MUHAMMAD IKRAM BIN UZIR ABDUL WAHAB

(HURUF BESAR)

mengaku membenarkan tesis * ini disimpan di Pusat Khidmat Maklumat Akademik, Universiti Malaysia

Sarawak dengan syarat-syarat kegunaan seperti berikut:

1. Tesis adalah hak milik Universiti Malaysia Sarawak.

2. Pusat Khidmat Maklumat Akademik, Universiti Malaysia Sarawak dibenarkan membuat salinan

untuk tujuan pengajian sahaja.

3. Membuat pendigitan untuk membangunkan Pangkalan Data Kandungan Tempatan.

4. Pusat Khidmat Maklumat Akademik, Universiti Malaysia Sarawak dibenarkan membuat salinan

tesis ini sebagai pertukaran antara institut pengajian tenggi.

5. ** Sila tandakan ( ∕ ) di kotak yang berkenaan

SULIT (Mengandungi maklumat yang berdarjah keselamatan atau kepentingan

Malaysia seperti yang termaktub di dalam AKTA RAHSIA RASMI 1972).

TERHAD (Mengandungi maklumat TERHAD yang telah ditentukan oleh

organisasi/badan di mana penyelidikan dijalankan).

TIDAK TERHAD

Disahkan Oleh:

_______________________ ________________________

(TANDATANGAN PENULIS) (TANDATANGAN PENYELIA)

Alamat Tetap: NO 7 JLN PRIMA SAUJANA 1/2B, CIK DAYANGKU SALMA BT

TMN PRIMA SAUJANA AWANG ISMAIL

43000 KAJANG SELANGOR. Nama Penyelia

Tarikh : _________________ Tarikh : _________________

√

CATATAN : * Tesis dimaksudkan sebagai tesis bagi Ijazah Doktor Falsafah, Sarjana dan Sarjana

Muda.

** Jika tesis ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasa /

organisasi berkenaan dengan menyatakan sekali sebab dan tempoh tesis ini perlu

dikelaskan sebagai SULIT atau TERHAD

“ I hereby declare that I have read this report and in my opinion this report is

sufficient in terms of scope and quality for the purpose for award of the Degree of

Bachelor of Engineering (Civil) with Honors ”.

Signature : ………………...…………………...............

Name of Supervisor : CIK DAYANGKU SALMA BT AWG ISMAIL

Date : ........................

“I hereby declare that this report is prepared personally with my own effort unless

references that have been cited accordingly in any part of the report”.

Signature : .……………………………...........................

Name of Author : MUHAMMAD IKRAM B UZIR ABDUL WAHAB

Date : ........................

APPROVAL SHEET

This project report attached here to, entitles “EFFECT OF COMPACTION

ENERGY ON ENGINEERING CHARACTERISTIC OF COMPACTED

SOIL” prepared and submitted by MUHAMMAD IKRAM B UZIR ABDUL

WAHAB (14623) as a partial fulfillment of the requirement for the Degree of

Bachelor of Engineering with Honours in Civil Engineering is hereby read and

approved by:

____________________________________ ........................

CIK DAYANGKU SALMA BT AWG ISMAIL Date

SUPERVISOR

EFFECT OF COMPACTION ENERGY ON ENGINEERING

CHARACTERISTIC OF COMPACTED SOIL

MUHAMMAD IKRAM B UZIR ABDUL WAHAB

This Thesis Is Propose To

Faculty of Engineering, Universiti Malaysia Sarawak

For Fulfillment of The Requirements for Bestowal

The Degree of Bachelor of Engineering with Honours

(Civil Engineering)

2010

This project report is dedicated to lovely people surround me,

especially my mum,

my brothers and sisters,

nephews and nieces,

friends

and lecturers,

thank you so much for their love and support

ACKNOWLEDGEMENT

With the name of Allah the Most Gracious and the Most Merciful

I wish to express my deepest gratitude to ALLAH the Almighty (SWT) for

His blessings that enrich me with more health and wisdom throughout my lifetime.

With the most respect, I would like to convey my sincere thanks and

appreciation to my thesis supervisor Miss Dayangku Salma bt Awg Ismail, who

endlessly guided and shared her knowledge throughout the completion of my thesis

work. I am really thankful to her for her encouragement and help in improving my

thesis.

Special thanks to the lab technicians, Haji Affandi for his unwavering

assistance in using the apparatus and preparing the materials during the laboratory

works.

I wish to express my appreciation to my family members for their concern

and love, which constantly provide the needed vitality in progressing all the way

through. Last but not least, thanks to my friends for their help and support upon

finishing this study.

ABSTRACT

Soil compaction is a significant stage in construction. When field compaction is

performed improperly, soil excessive settlement could occur and result in

unnecessary maintenance costs or structure failure. The objective for this research is

to study the effect of compaction energy to compaction characteristic of granular

soil. Granular soil is widely used as a replacement soil when dealing with soft soil

such as peat and very soft clay. Furthermore, granular soil is commonly used in

pavement of runaway which requires strong base to sustain heavy load from

vehicles. Compactive effort is one factor that affects the quality of compaction.

Standard and Modified Proctor had been used to show the effect of compactive effort

to the river sand and laterite soil samples. The study proved that the maximum dry

density of soils increases when the compactive effort increases which also

contributed to higher shear strength.

ABSTRAK

Pemadatan tanah merupakan proses yang penting dalam pembinaan. Ketika

pemadatan lapangan dilakukan tidak mengikut prosedur, pemendapan berlebihan

boleh berlaku dan menyebabkan kos penyelenggaraan yang tidak tinggi atau

kegagalan struktur. Tujuan kajian ini adalah untuk mempelajari kesan tenaga

pemadatan terhadap ciri-ciri pemadatan tanah granular. Tanah granular digunakan

secara meluas sebagai tanah pengganti terhadap tanah lembut seperti tanah gambut

dan tanah liat yang tertentu. Tambahan lagi, tanah granular biasanya digunakan

sebagai lapisan landasan kapal terbang yang memerlukan asas yang kuat untuk

menampung berat yang berlebihan. Tenaga pemadatan adalah salah satu faktor yang

mempengaruhi kualiti pemadatan. Proctor piawaian dan Proctor diubahsuai telah

digunakan untuk menunjukkan kesan usaha tenaga pemadatan terhadap sampel pasir

sungai tanah laterit. Kajian membuktikan bahawa kepadatan kering maksimum tanah

meningkat apabila tenaga pemadatan meningkatkan yang juga memberi kesan

terhadap kekuatan ricih yang lebih tinggi.

TABLE OF CONTENTS

PAGES

Acknowledment

Abstract

Abstrak

Table of Contents

ii

iii

iv

v

List of Figures

List of Tables

viii

x

List of Symbols xi

Chapter 1 INTRODUCTION

1.1 Background 1

1.2 Problem Statement 2

1.3 Objective 4

1.4 Scope of Work

1.5 Outline of Thesis

4

4

Chapter 2 LITERATURE REVIEW

2.1 General Overview 7

2.2 Theory of Compaction 8

2.3 Introduction on Granular Soils 12

2.4 Shear strength of Granular Soil 12

2.5 Moisture Content 13

2.6 Specific Gravity 14

2.7 Void Ratio and Porosity 14

2.8 Atterberg Limit

2.9 Standard Proctor Test

2.10 Modified Proctor Test

2.11 Factors Affecting Compaction

2.11.1 Effect of Soil Type

2.11.2 Effect of Compaction Effort

2.12 Field Compaction

2.12.1 Factors Affecting Field Compaction

17

17

18

19

19

20

21

23

Chapter 3 METHODOLOGY

3.1 Introduction 24

3.2 Data Collection 25

3.3 Data Analysis

3.4 Collection of Sample

3.5 Physical Properties Determination

3.5.1 Particle Size Distribution

3.5.2 Determination of Specific Gravity

3.5.3 Determination of Natural Moisture Content

3.6 Engineering Properties Determination

3.6.1 Determination of Compaction Parameters

3.6.2 Determination of Shear Strength Parameters

25

25

26

26

27

28

28

29

30

Chapter 4

Chapter 5

RESULTS AND DISCUSSION

4.1 Introduction

4.2 Physical Properties of Compacted Soil

4.2.1 Natural Moisture Content

4.2.2 Particle Size Distribution

4.2.3 Atterberg Limit Test

4.2.4 Specific Gravity

4.3 Engineering Properties of Compacted Soil

4.3.1 Compaction Characteristic of Two Sample of

Soils

4.3.2 Shear Strength Parameters of Compacted Soils

4.4 Summary of Findings

CONCLUSIONS AND RECOMMENDATIONS

5.1 Introduction

5.2 Conclusion

5.3 Recommendations

33

33

34

34

36

37

37

37

40

43

45

45

48

References

Appendices

49

52

LIST OF FIGURES

FIGURE NO. TITLE

PAGES

2.1 Typical Compaction Curve for A Given

Compaction Effort

8

2.2 Typical Standard and Modified Proctor

Compaction Curve for An Identical Soil Sample

9

2.3

2.4

2.5

2.6

2.7

3.1

3.2

3.3

Density of Sand Under Vertical Acceleration

Ideal Granular Soil of Uniform Spherical Particles

Different Consistency Limit

Typical Compaction Curve for Four Different Soil

Effect of Compaction Energy on The Compaction

of A Sandy Clay

Sieving Test Machine

Compaction Test Apparatus

Direct Shear Test Machine

11

16

17

20

21

27

30

31

3.4

4.1

4.2

4.3

4.4

Flowchart of Activities for The Study

Particle Size Distribution Curve

Condition of Samples in Plasticity Chart

Dry Density versus Moisture Content Curve for

River Sand

Dry Density versus Moisture Content Curve for

32

35

36

38

39

4.5

4.6

4.7

4.8

Laterite Soil

Shear Stress versus Strain Curve for Standard and

Modified Proctor of River Sand

Shear Stress versus Normal Stress for Standard

and Modified Proctor of River Sand

Shear Stress versus Strain Curve for Standard and

Modified Proctor of Laterite Soil

Shear Stress versus Normal Stress for Standard

and Modified Proctor of Laterite Soil

41

41

42

42

LIST OF TABLES

TABLE NO. TITLE

PAGES

3.1 Standard Proctor Test Method 29

3.2 Modified Proctor Test Method 29

4.1

4.2

5.1

5.2

Atterberg Limit Value for Samples

Specific Gravity Value

Summary of Compaction Tests

Summary of Direct Shear Test Parameters

36

37

46

47

LIST OF SYMBOLS

Gs - Specific Gravity

ms - Mass of Soil / Solid

Vs - Volume of Solid

ρw - Unit Weight of Water

e - Void ratio

- Porosity

W - Moisture content / Water Content

Vs - Volume of Solid

LL - Liquid Limit

PL - Plastic Limit

γ - Unit weight of compaction

γd - Dry unit weight

CI - Clay intermediate

EFFECT OF COMPACTION ENERGY ON ENGINEERING CHARACTERISTIC

OF COMPACTED SOIL

A.I. Dayangku Salma, U.A.W. Muhammad Ikram

Department of Civil Engineering, Faculty of Engineering, Universiti Malaysia Sarawak (UNIMAS), 94300,

Kota Samarahan, Sarawak, Malaysia.

Abstract

Soil compaction is a significant stage in construction. When field compaction is performed

improperly, soil excessive settlement could occur and result in unnecessary maintenance costs or structure

failure. The objective for this research is to study the effect of compaction energy to compaction characteristic

of granular soil. Granular soil is widely used as a replacement soil when dealing with soft soil such as peat and

very soft clay. Furthermore, granular soil is commonly used in pavement of runaway which requires strong base

to sustain heavy load from vehicles. Compactive effort is one factor that affects the quality of compaction.

Standard and Modified Proctor had been used to show the effect of compactive effort to the river sand and

laterite soil samples. The study proved that the maximum dry density of soils increases when the compactive

effort increases which also contributed to higher shear strength.

Keywords: Soil compaction, compaction energy, Granular soil.

I. Introduction

Compaction of soil is the process by which the solid particles are packed more closely together, usually

by mechanical means, thereby increasing the dry density of the soil. The state of compaction is measured in

terms of dry density. This achieve by a process of compaction is found to depend upon energy expended during

compaction, and also on the water content during compaction (Berry and Reid, 1987). In this research, the granular soils will be used as an experimental material in the determination of its

characteristic. Granular soils, for example sand and gravel normally is use as a replacement material to replace

the soft soil. Mat foundation can be applied to this type of soil but if there was a little or no sand and gravel at

the site, the building must be placed on piles to firm soil. Without proper soil compaction, many concrete

structures are doomed to perform poorly (Lambe and Whitman, 1979).

Braja M. Das (1941) studied that for sands, the dry unit weight has a general tendency first to decrease

as moisture content increases, and then to increase to a maximum value with further increase of moisture. The

initial decrease of dry unit weight with increase of moisture content can be attributed to the capillary tension

effect. At lower moisture content, the capillary tension in the pore water inhibits the tendency of the soil

particles to move around and be densely compacted.

II. Objectives

1. To identify compaction parameters of granular soil.

2. To investigate the effect of compaction energy to soil shear strength.

III. Methodology

Since this study is fully base on laboratory work, the soil samples were collected from Kota Samarahan area for

the laterite soil and from the Sungai Sarawak for the river sand. The laterite soil was taken at the nearside of

new highway to be ahead to Kg Baru, Kota Samarahan. The sample is taken to the laboratory and the tests

conducted according to British standards. The test is divided into two different tests which are physical

properties test and engineering test. The classification test is to determine the index properties such as specific

gravity, water content or etc. There are two test conducted in engineering test which is Proctor test and direct

shear test.

IV. Results and Discussion

Results on Physical Properties

Natural Moisture Content

The natural moisture content or water content of samples is determined by using oven drying method. From the

calculation, the average natural moisture content of river sand is 23.3% while for laterite soil is 30%.

Particle Size Distribution

Figure 1: Particle Size Distribution Curve

Sieving test was done to identify percentage of gravel, sand, silt, and clay. For river sand sample, it is obviously

the sample contain high percentage of sand which 86.28% and gravel 10% while laterite soil shows 77.28% of

sand and 19.11% gravel.

Atterberg Limit Test

Table 1: Atterberg Limit Value for Samples

Sample Liquid

Limit

(LL)

Plastic

Limit

(PL)

Plasticity

Index (PI)

Laterite

Soil

0.41 0.25 0.16

Through Atterberg limit test, liquid limit and plastic limit for the samples will be known. Determination of

liquid limit is referring to moisture content at 20mm cone penetration while plastic limit is defined as average of

the moisture content (%).From the plasticity chart laterite soil is fall under Clay Intermediate (CI) range. The

range is between 40 to 60%.

Specific Gravity

Table 2: Specific Gravity Value

Sample Gs

River sand 2.64

Laterite soil 2.57

The data show that Gs value of river sand is higher than the laterite soil. The value meets the standard range for

sand which is 2.6-2.7.

0.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 90.00

100.00 110.00

0.01 0.1 1 10 100

% P

assi

ng

Particle Size (mm)

% Passing vs Particle Size

river sand

laterite soil

sand gravel

Results on Engineering Properties

Compaction Characteristics of Two Samples of Soil

Figure 2: Dry density versus moisture content

curve for river sand

Figure 2 shows compaction curve of compacted

river sand. It was described that optimum moisture

content (OMC) and maximum dry density (MDD)

using standard Proctor were 16% and 1.59 Mg/m3

respectively. Modified Proctor produced better

result of OMC and MDD which 14.2% and 1.74

Mg/m3 respectively.

As the weight hammer increase and higher the drop

height is, the deeper compaction will be and

resulting increase of bulk unit weight. This

contributes to higher MDD of modified Proctor

compares to standard Proctor.

Figure 3: Dry density versus moisture content

curve for laterite soil

Figure 3 illustrates compaction curve of compacted

laterite soil. It was observed that OMC and MDD

of laterite soil using standard Proctor test were 18

% and 1.78 Mg/m3 respectively. On the other hand,

Modified Proctor test produced better results which

OMC is 15.5 % and MDD is 1.82 Mg/m3.

The relation between the moisture content and the

dry density of soil is to obtain the maximum dry

unit weight and the optimum moisture content for a

soil. The maximum dry unit weight is obtained

when there is no air void space, which is when the

degree of saturation equals 100%. The dry density

of laterite soil is higher than the river sand. It is

means that the soil particle of laterite soil is more

compact and closely to each other.

It can be summarized that experimental results

show increase in compaction energy applied to

both sample produces better maximum dry density.

Meanwhile, moisture content will be decreased. It

was also observed that river sand sample was well

compacted compare to laterite soil sample.

Shear Strength Parameters of Compacted Soils

Figure 4 shows shear stress versus strain curve for

standard and modified Proctor of river sand. Shear

stress is increased when the load increased.

However, shear stress for modified Proctor sample

is lower than standard Proctor sample. This is

because the more compaction energy applied will

produce parallel orientation to soil particle. Thus,

soil particles become close to each other and shear

strength increased. From the curves, maximum

shear stress every load applied was obtained and

will be used to determine shear strength

parameters.

Figure 5 illustrates shear stress versus normal stress

for standard and modified Proctor of river sand

sample. It was observed that cohesion for standard

Proctor of river sand is slightly different from

modified Proctor which standard Proctor is 0kN/m2

and modified Proctor is 8kN/m2. the friction angle

for standard Proctor is 27.77° and modified Proctor

is 20.3° which is lesser than standard.

1.20

1.30

1.40

1.50

1.60

1.70

1.80

0 5 10 15 20 25 30

Dry

Den

sity

, M

g/m

3

Moisture Content, %

Dry Density Vs Moisture Content For River Sand

Standard Proctor

Modified Proctor

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

5 15 25 35 45

Dry

Den

sity

, M

g/m

3

Moisture Content, %

Dry Density versus Moisture content For Laterite Soil

Standard Proctor

Modified

Proctor

Figure 4: Shear Stress versus Strain Curve for

Standard and Modified Proctor of River Sand

Figure 5: Shear Stress versus Normal

Stress for Standard and Modified Proctor of River

Sand

Figure 6: Shear Stress versus Strain Curve

for Standard and Modified Proctor of Laterite Soil

Figure 7: Shear Stress versus Normal

Stress for Standard and Modified Proctor of

Laterite Soil

Different in normal stress applied will give

different soil strength. Differential in compaction

effort also influence the soil strength. When

compaction energy applied is higher, the more

strengthen the soil.

From the figure 4.8, the value of cohesion, c for the

modified Proctor is higher than standard Proctor

which is 20 kN/m2 and 13 kN/m

2 respectively. The

higher value of c is shows the strength value of soil

internal forces to hold soil particles together with

the soil mass. The friction angle for standard

Proctor is 16.87° which much greater than 15.82°

for modified Proctor. It shows that when the

compaction energy applied becomes greater, the

value of friction angle will become smaller.

Summary of Findings

From the experimental works done, it can

be observed that natural moisture content of laterite

soil is higher than river sand which is 30% and

23.33% respectively.

Both river sand and laterite soil is

classified as CI (clay intermediate) based on

plasticity chart. The specific gravity of both

samples is fall under granular soil range which is

2.6-2.7. Specific gravity for river sand is 2.64 while

laterite soil is 2.57 (acceptable).

Maximum dry density of modified Proctor

for both samples is higher than standard Proctor

test. This shows that when compactive effort

increased, dry density also increased. The optimum

moisture content is decreased when increased in

compaction energy thus causing increased in soil

shear strength.

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

0.00 5.00 10.00 15.00 20.00

She

ar S

tre

ss (

kg/c

m2

)

% Strain

Shear Stress vs % Strain

Standard Proctor

Modified Proctor

1

2

3

0

0.5

1

1.5

0 0.5 1 1.5 2 2.5 3 3.5

She

ar

stre

ss,

kg/c

m2

Normal Stress, kg/cm2

Max Stress vs Normal Load

Standard Proctor

Modified Proctor

0

0.5

1

1.5

2

0 0.5 1 1.5 2 2.5 3 3.5

Shea

r st

ress

, kg/

cm2

Normal Stress, kg/cm2

Max Stress vs Normal Load

Standard Proctor

Modified Proctor

0.00

0.20

0.40

0.60

0.80

1.00

1.20

0.00 10.00 20.00 30.00

Shea

r St

ress

(kg

/cm

2)

% Strain

Shear Stress vs % Strain

Standard Proctor Modified Proctor 1

2

3

V. Conclusion

From the analysis and results obtained, some physical and engineering parameters were generated.

These parameters are leads to achieve the objective of this paper and get better understanding about the soil

compaction. Conclusions that can be made are:

i. Increased in compactive effort will increase the maximum dry density and decreased optimum moisture

content. It is proven by the analyses that have been made for both samples. When the higher energy

applied to the soil, the air void between the soil particles is decreases and water is hard to entering the

soil, hence increases the maximum dry density.

ii. When the weight and height of hammer are increase, it gives more compaction energy to the soil. The

soil particle will be close to each other and causing the bulk unit weight heavier. The compaction

energy per unit volume (E) used for the standard Proctor test can be described as E = [( No of

blows/layer) x (no of layers) x (weight of hammer) x (drop of hammer)]/ volume of the mould. If the

compactive effort per unit volume is altered, the moisture unit weight curve is also altered.

iii. Cohesion value, c between standard and modified Proctor for both sample is not show a big different

but angle of friction, φ is decrease as the energy increase.

iv. The normal stress applied will affect the soil strength. Soil strength will increase as the increase in

normal stress.

v. Shear stress of river sand is higher than laterite soil. River sand gives more stabilization than laterite

soil.

It is important to have deep understanding on compaction energy and its effect to the soil structure.

References

[1] Berry, P. L., & Reid, D. (1987). An Introduction to Soil Mechanics. Shoppenhagen Road, Maidenhead,

Berkshire, England: McGraw-Hill.

[2] Das, B.M. (1941) Principle of Geotechnical Engineering, third edition. Boston, USA: PWS Publishing.

[3] Lambe, T.W., & Whitman, R.V. (1979). Soil Mechanics, 605 Third Avenue New York, John Wiley &

Sons.

1

CHAPTER 1

INTRODUCTION

1.1 Background

Compaction of soil is the process by which the solid particles are packed

more closely together, usually by mechanical means, thereby increasing the dry

density of the soil. In construction, this is a significant part of the building process.

Improper compaction techniques can cause soil having settlement and the

maintenance cost will increase or structure will failure. Almost all types of building

sites and construction projects utilize mechanical compaction techniques. The state

of compaction is measured in terms of dry density. This achieve by a process of

compaction is found to depend upon energy expended during compaction, and also

on the water content during compaction (Berry and Reid, 1987).

In this research, the granular soils will be used as an experimental material in

the determination of its characteristic. Granular soils range in particle size from .003"

to .08" (sand) and .08" to 1.0" (fine to medium gravel). Granular soils are known for

2

their water-draining properties. The response of soil to moisture is very important, as

the soil must carry the load year-round. Rain, for example, may transform soil into a

plastic state or even into a liquid. In this state, soil has very little or no load-bearing

ability.

Granular soils, for example sand and gravel normally is use as a replacement

material to replace the soft soil. Mat foundation can be applied to this type of soil but

if there was a little or no sand and gravel at the site, the building must be placed on

piles to firm soil.

One of the common uses of granular soil is in the pavement of roads or air

field. The base course of the pavement consists of gravel commonly, but in certain

situation like in the desert, there was a shortage of gravel but abundance of desert

sand. Under these circumstances, it was more economical to improve properties of

the soil than to use gravel over large distances.

1.2 Problem Statement

In this world, soil is the most plentiful construction material and it is

essentially locally available construction material in any region. The civil engineer

must select a proper type of soil and the method of placement, and then control the

actual placement. Soils are usually compacted by using compaction machineries for

example vibrator rollers and pneumatic rollers. Without proper soil compaction,