PERFORMANCE OF HORIZONTAL SOIL HOOK SYSTEM IN SAND

HAMED NIROUMAND

A thesis submitted in fulfillment of the

requirements for the award of the degree of

Master of Engineering (Geotechnics)

Department of Geotechnics and Transportation

Faculty of Civil Engineering

Universiti Teknologi Malaysia

March, 2010

May 05, 2010

Librarian

Perpustakaan Sultanah Zanariah

UTM, Skudai

Johor

Sir,

CLASSIFICATION OF THESIS AS RESTRICTED PERFORMANCE OF HORIZONTAL SOIL HOOK SYSTEM IN SAND

Please be informed that the above mentioned thesis entitled " PERFORMANCE

be classified as a period of three (3) years from the date of this letter. The reasons

for this classification are

(i)

(ii)

(iii)

Thank you.

Sincerely yours,

Department of Geotechnical Engineering,

Hamed Niroumand

OF HORIZONTAL SOIL HOOK SYSTEM IN SAND " RESTRICTED for

This system is a new method and invention,

Prof.Dr.Khairul Anuar Kassim

Faculty of Civil Engineering,Universiti Teknologi Malaysia

iii

Dedication

To my wife & my parents

iv

ACKNOWLEDGMENT

The author wishes to express profound gratitude to his advisor Prof. Dr.

Khairul Anuar Kassim, for his direct supervision, continues advice and guidance

throughout the work of this research. The author was gratefully acknowledgement

invaluable, help, and patience.

Thanks and appreciations are due to Department of Geotechnical

Engineering, who provided valuable discussion in this research. Acknowledgment

are also due to the entire laboratory technician Mr. Zul and another their

colleagues who patiently provided assistance on the experimental portion of this

research.

Finally, the author wishes to express special thanks and appreciate to his

parents and family for the emotional support and love. Special thanks to author s

wife, for her love, sacrifice and continuous struggle towards the accomplishment

of this research.

v

ABSTRACT

Structures like buried pipelines, transmission towers and earth structures

subjected to considerable vertical or horizontal pullout forces are usually

supported by anchors. The anchors are helical or plate systems which require

excavation and grout in their applications. During the last fifty years, many

researchers focused on pullout capacity of anchors. Comparison between

experimental and theoretical analyses has been performed to validate the ultimate

pullout load of anchors. The aim of this research is to obtain breakout factor and

ultimate pullout capacity load of Soil Hook System (SHS) and compares it with

previous finding by different researchers. SHS is a new anchor system base on the

state of the art of plate anchors that does not require grout and excavation in their

applications. The experiments were conducted in a chamber box. Two sizes of

SHS with the length 297 and 159 mm were used. For the 159 mm long SHS, an

embedment ratio between 1 and 7 were employed. For the SHS of length 297mm

the embedment ratio used were between 1 to 4. Both SHS were tested in loose and

dense sand. Dry sand with unit weight of

and

were used for loose and dense sand packing respectively. The

results of a comprehensive theoretical analysis on the behavior of SHS were

presented. These include hook size, ultimate pullout capacity; pull out load, and

breakout factor. It was found that the pullout load capacity and breakout of SHS

was similar to the works done by the previous researchers in plate anchors. The

results show that the failure mechanism pattern around the SHS at shallow and

deep levels were similar to the rupture surface pattern from previous researchers.

This research has solved the problem of the installation of anchors into sand with

SHS without the need to grout or excavate.

vi

ABSTRAK

Struktur seperti rangkaian paip tertanam, menara talian dan struktur bumi

yang dikenakan daya tarikan menegak atau mendatar kebiasaan nya disokong oleh

penambat. Penambat sistem heliks atau plat memerlukan penggalian dan turapan

didalam penggunaannya. Sepanjang lima puluh tahun, para penyelidik hanya

menumpukan pada keupayaan tarik keluar penambat. Perbandingan antara

analisis eksperimen dan teori telah dilakukan untuk menilai semula beban

penarikan keluar muktamad penambat. Tujuan utama penyelidikan ini adalah

untuk mendapatkan nilai faktor putus dan keupayaan tarikan keluar muktamad

sistem cangkuk dan membandingkannya dengan penyelidikan sebelumnya oleh

penyelidik dari seluruh dunia. Sistem cangkuk tanah merupakan sistem penambat

baru kerana seni reka bentuk pada penambat yang tidak memerlukan penggalian

dan turapan dalam penggunaannya. Ujikaji dijalankan di dalam kotak kebuk yang

memuatkan dua saiz sistem cangkuk dengan panjang 297 dan 159 mm. Untuk

sistem cangkuk tanah bagi, panjang 159 mm, tanah nisbah kedalaman yang

digunakan adalah antara 1 dan 7. Sistem cangkuk tanah bagi panjang 297mm

nisbah kedalaman yang digunakan adalah antara 1 hingga 4. Kedua-dua sistem

cangkuk ditanam dalam pasir longgar dan padat. Pasir kering dengan berat unit

dan

digunakan untuk pasir longgar dan

padat. Keputusan analisis teori yang menyeluruh tentang ciri-ciri sistem tanah

cangkuk dihuraikan. Ini termasuk dimensi cangkuk, keupayaan tarik keluar

muktamad, beban tarik keluar dan faktor putus. Dapat dilihat bahawa keupayaan

beban tarik keluar dan putus bagi sistem cangkuk adalah sama dengan hasil ujikaji

oleh penyelidik sebelumnya dalam penambat plat. Keputusan kajian menunjukkan

bahawa pola mekanisma kegagalan di sekitar cangkuk tanah pada paras cetek dan

dalam adalah sama dengan pola pecah permukaan oleh para penyelidik yang lepas.

Penyelidikan ini telah menyelesaikan masalah pemasangan penambat didalam

tanah pasir dengan sistem cangkuk tanah tanpa perlu penggalian dan turapan.

vii

TABLE OF CONTENTS

CHAPTER CONTENTS PAGE

TITLE i

DECLARATION ii

DEDICATION iii

ACKNOWLEDGEMENT iv

ABSTRACT v

ABSTRAK vi

LIST OF TABLES xi

LIST OF FIGURES xii

LIST OF NOTATIONS xvi

LIST OF APPENDICES xviii

1 INTRODUCTION 1

1.1 Introduction 1

1.2 Statement of Problem 1

1.3 Objectives of Research 2

viii

1.4 Scope of Study 2

1.5 Thesis Outline 3

1.6 Expected Finding 4

2 LITERATURE REVIEW 5

2.1 Introduction 5

2.2 Review of Previous Experimental Works 6

2.2.1 Methods of Analysis in Anchor Plate 8

2.2.2 Previous Experimental Works 9

2.2.3 Recent Experimental Work 14

2.2.4 Limitations of Experimental Work 17

2.3 Preview of Previous Theoretical and Numerical Work 18

2.3.1 Numerical Methods 19

2.3.2 Recent Numerical Work 28

2.3.3 Limitations of Numerical Work 35

3 RESEARCH METHODOLOGY 38

3.1 Introduction 38

3.2 Testing Program 38

3.3 Chamber Box Arrangement 39

ix

3.4 Testing Procedure in Chamber Box 42

3.5 Experimental Program 43

3.5.1 Properties of Sand 43

3.5.2 Soil Hook System (SHS) Materials 47

3.5.3 Chamber Box 49

3.5.4 Failure Mechanism 52

3.6 Theoretical Analysis 54

4 EXPERIMENTAL RESULTS 56

4.1 Introduction 56

4.2 Soil Hook System (SHS) in Chamber Box 57

4.2.1 Soil Hook System (SHS) in Chamber Box 57

4.2.1.1 The Effect of Embedment Ratio 57

4.2.1.2 The Effect of Sand Density 63

4.2.1.4 Break out Factor 64

4.3 Failure Mechanism 66

4.3.1 Failure Mechanism in Loose Sand 66

4.5.2 Failure Mechanism in Dense Sand 71

4.5.3 Summary of Failure Mechanism 74

x

5 COMPARISON BETWEEN EXISTING THEORIES AND

EXPERIMENTAL WORKS 75

5.1 Introduction 75

5.2 Assumption in Comparison Work 75

5.3 Comparison of the Breakout Factor and Existing Theoretical Breakout Factor 76

5.3.1 Comparison of the Breakout Factor and Existing Theoretical Breakout Factor in Loose Sand 77

5.3.2 Comparison of the Breakout Factor and Existing Theoretical Breakout Factor in Dense Sand 79

6 CONCLUSIONS 82

6.1 Conclusion on the Research 82

6.2 Suggestion for Future Research 83

REFERENCES 84

APPENDICES 87

xi

LIST OF TABLES

Table Title Page

2.1 Last Experimental Models Tests on Horizontal Anchors in sand 17

2.2 Previous Theoretical Analysis on Horizontal Anchors in sand 37

3.1 Parameters of Sample Tested 46

xii

LIST OF FIGURES

Figure Title Page

2.1 Failure Surface Assumed by Mors (1959) 8

2.2 Failure Surface Assumed by Downs & Chieurzzi (1959) 9

2.3 Failure Surface Assumed by Balla (1961) 10

2.4 Laboratory Test Devices of Lidija and Pavao (2003) 14

2.5 Scheme of Laboratory Tested for Pullout Test of Lidija and Pavao (2003) 15

2.6 Load/Displacement Curves of Murray and Geddes (2006):

(a) Very Dense Sand; (b) Medium Dense Sand 15

2.7 3D view of the chosen experimental set up of Kumar and Bhoi (2008) 16

2.8 Failure surface assumed by Mors (1959) 20

2.9 Anchor under pullout test 21

2.10 Variation of F1+F3 Based on Balla s Result (1961) 22

2.11 Variation of Ku Based on Meyerhof and Adams (1968) 24

2.12Variation of m Based on Meyerhof and Adams (1968) 24

2.13 View of Tests of Vesic (1971) 25

2.14 Breakout Factor in Strip Anchor Plate of Vesic (1971) 25

2.15 Failure Surface assumed by Veesaert and Clemence(1977) 26

2.16 Variation of Capacity Factor F

in Rowe and Davis (1982) 27

xiii

2.17 Problem Definition by Merfield and Sloan (2006) 30

2.18 Mesh for Square Anchor Plate by Merfield and Sloan (2006) 30

2.19 Mesh for Circular Anchor Plate by Merfield and Sloan (2006) 31

2.20 Very Fine Mesh in Analysis of a Strip Anchor with an Embedment Ratio L/D=7 in PLAXIS by Dickin and Laman (2007) 32

2.21 Coarse Mesh in Analysis of a Strip Anchor with an Embedment Ratio L/D=7 in PLAXIS by Dickin and Laman (2007) 32

2.22 Breakout Factors Finding in Loose Sand in Dickin & Laman (2007) 33

2.23 Breakout Factors Finding in Dense Sand in Dickin & Laman (2007) 33

2.24 Definition of the Problem by Kumar and Bhoi (2008) 34

2.25 (a) Position and Loading of Anchors & (b) Boundary Condition by Kuzer and Kumar (2009) 35

3.1 View of Pullout Test 39

3.2 View Elevation of Data Logger 40

3.3 View of Motor Winch System 40

3.4 View of Soil Hook Systems (SHS) Details 41

3.5 View of Primary Vehicles 41

3.6 Top View of Chamber Box 42

3.7 View of Seive Test 44

3.8 Variations of Grain Size Distribution of Sand 44

3.9 View of Direct Shear Test 45

3.10 View of Variations of Shear Stress with Normal Stress 45

3.11 Soil Hook Systems (SHS) with Length 297mm & 159mm 47

3.12 Small Soil Hook System (SHS) with Length159mm 48

3.13 View of Analysis of Soil Hook System (SHS) in 4m in CATIA 48

xiv

3.14 View of Finite Element Mesh of Soil Hook System (SHS) 49

3.15 Sand Packing in Chamber Box 50

3.16 Position of Soil Hook System (SHS) in Compacting 51

3.17 View of Line Definer in Pullout 51

3.18 View of Testing Still Running 52

3.19 View of Failure Mechanism 53

4.1 Variations of Pullout Load with Embedment Ratio L/D for Small Soil Hook System (SHS) in Loose Sand 58

4.2 Variations of Pullout Load with Embedment Ratio L/D for Small Soil Hook System (SHS) in Dense Sand 58

4.3 Variations of Pullout Load with Embedment Ratio L/D for Big Soil Hook System (SHS) in Loose Sand 59

4.4 Variations of Pullout Load with Embedment Ratio L/D for Big Soil Hook System (SHS) in Dense Sand 59

4.5 Result of Pullout Load with Embedment Ratio L/D for Small Soil Hook System (SHS) in Loose Sand 60

4.6 Result of Pullout Load with Embedment Ratio L/D for Big Soil Hook System (SHS) in Loose Sand 61

4.7 Result of Pullout Load with Embedment Ratio L/D for Small Soil Hook System (SHS) in Dense Sand 62

4.8 Result of Pullout Load with Embedment Ratio L/D for Small Soil Hook System (SHS) in Dense Sand 62

4.9 Variations of pullout Load with Embedment Ratio L/D for Small Soil Hook System (SHS) in Loose and Dense Sand 63

4.10 Variations of pullout Load with Embedment Ratio L/D for Big Soil Hook System (SHS) in Loose and Dense Sand 64

4.11 Variations of Break out with Embedment Ratio L/D for Small and Big Soil Hook System (SHS) in Loose Sand 65

4.12 Variations of Break out with Embedment Ratio L/D for Small and Big Soil Hook System (SHS) in Dense Sand 65

xv

4.13 Failure Mechanism Setup 67

4.14 Front Elevation for Failure Mechanism Test in Loose Sand 67

4.15 Front Elevations for Failure Mechanism Testing in Loose Sand. Rotation Zone Was Start to Developed Shear Plane Indicated by Lines. 68

4.16 Front Elevations for Failure Mechanism Testing in Loose Sand. Rotation Zone Was Indicated by Lines. 68

4.17 Front Elevations for Failure Mechanism Testing in Loose Sand. Different Steps of Rotation in Small Model Were Indicated by Lines. 69

4.18 Front Elevations for Failure Mechanism Testing in Loose Sand. Last Step of Rotation in Small Model Was Indicated by Lines. 69

4.19 Schematic Diagram of Failure Mechanism in Loose Sand 70

4.20 Final Schematic of Failure Zones of Small Soil Hook System (SHS) in Loose Sand 70

4.21 View of Setup Failure Mechanism in Dense Sand 71

4.22 View of Different Dense Sand Layers 72

4.23 Front Elevation for Failure Mechanism Testing of Small Soil Hook System (SHS) in Dense Sand, Model Start to Move Indicated by Lines 72

4.24 Front Elevation for Failure Mechanism Testing of Small Soil Hook System (SHS) in Dense Sand, Failure Zone in First Time Indicated by Lines 73

4.25 Front Elevations for Failure Mechanism Testing in Dense Sand. Failure Zone in Small Model Was Indicated by Lines. 73

4.26 Final Schematic of Failure Zones of Small Soil Hook System (SHS) in Dense Sand 74

xvi

LIST OF NOTATIONS

A : Area of Anchor Plate

B : Length of Anchor Plate/ Soil Hook System (SHS)

: Coefficient of Uniformity

D : Width of Anchor Plate / Soil Hook System (SHS)

: Effective Grain Size

: Uniformity of Sand

e : Void Ratio

: Specify Gravity

H : Depth of Soil

: Earth Pressure Coefficient at Rest

L : Depth of Soil above Anchor Plate/ Soil Hook System (SHS)

L/D : Embedment Ratio

n : Porosity

P : Pullout Load

: Ultimate Pullout Load

t : Time

: Unit Weight of Soil

? : Soil Friction Angle

: Breakout Factor

: Dry Unit Weight of Soil

M : Mass of Soil

V : Volume of Soil

: Shape Factor

: Critical Embedment Ratio

W : Effective Weight of Soil

: Shearing Resistance

xvii

: Force Below of Area

: Nominal Pullout Coefficient of Earth Pressure on a Convex

Cylindrical

: Relative Porosity

: Density Index

xviii

LIST OF APPENDICES

Appendix Title Page

Appendix A Properties of shear direct test in dense sand 88

Appendix B Properties of shear direct test in loose sand 93

Appendix C Design and modeling of Soil Hook System (SHS) in CATIA 98

Appendix H Variation of breakout factor on author s empirical formula 147

Appendix I Variation of breakout factor based on Balla s theory (1961) 148

Appendix J Variation of breakout factor based on Balla s theory (1961) 150

Appendix K Variation of breakout factor in Meyerhof & Adams theory (1968) 152

Appendix L Variation of breakout factor in Meyerhof & Adams theory (1968) 154

Appendix M Variation of breakout factor in Vesic theory (1971) in loose sand 156

Appendix N Variation of breakout factor in Vesic theory (1971) in dense sand 158

Appendix O Variation of breakout factor in Rowe and Davis theory (1982) 160

Appendix P Variation of breakout factor in Rowe and Davis theory (1982) 161

Appendix Q Variation of breakout factor in Murray & Geddes theory (1987) 162

Appendix R Variation of breakout factor in Murray & Geddes theory (1987) 163

Appendix S Variation of breakout factor in Dickin & Laman finding (2007) 164

Appendix T Variation of breakout factor in Dickin & Laman finding (2007) 165

1

CHAPTER 1

INTRODUCTION

1.1 Introduction

Structures such as transmission towers, tunnels, sea walls, buried pipelines,

retaining walls and others are subjected to considerable pullout forces. In such

cases, an economic design solution may be obtained through the use of tension

members. These elements, which are related to anchors, are generally fixed to the

structure and embedded in the ground to effective depth so that they can resist

uplifting forces.

1.2 Statement of Problem

Most of the anchoring system in this country is a grout base anchoring .The

installation may take several days

Soil Hook System (SHS) is a new anchoring

with innovative state of the art plate which can be installed in sand without having

to grout it. It is expected from this system to increase the speed of construction

and cost effective.

2

1.3 Objectives of Research

The main aim of this research is to investigate the behavior of ultimate

pullout capacity of Soil Hook System (SHS) in dry loose and dense sand. In order

to achieve the aim of study, five objectives have been identified:

i. To investigate the ultimate pullout capacity of two size Soil Hook System

(SHS) in loose and dense sand,

ii. To make new empirical formula based on the result of Soil Hook System

(SHS) in sand , due to real tests in soil laboratory,

iii. To compare the break-out factor in Soil Hook System (SHS) with previous

works by different researches.

iv. To design rigid of Soil Hook System (SHS) in CATIA , that it is a

mechanical software,

1.4 Scope of Study

In this study special attention is provided to Soil Hook System (SHS) that

is investigated with only horizontal pullout load test in dry Kota Tinggi sand. The

data for this study will be obtained from test data in geotechnical laboratory in

University Technology Malaysia.

3

1.5 Thesis Outline

Reviews of previous researchers

activities are discussed in Chapter Two

including the analytical procedures. This chapter is a review based on the

Introduction to the Topic of plate anchors because Soil Hook System (SHS) is a

type of art special in plate anchors.

Field test and two model laboratory tests will be used to research the

performance of horizontal Soil Hook System (SHS) subjected to pullout loading.

Field studies in plate anchors, reported by last researchers, will be discussed in

Chapter Two.

Review of the theories and numerical analysis in plate anchors from

previous researchers will be discussed in Chapter Two, including the analytical

procedures. Analyses, beginning from Meyerhof and Adams (1968) until the most

recent analysis such as Kuzer and Kumar (2009), are also reviewed.

Research methodology will be discussed in Chapter Three. The Soil Hook

Systems (SHS) tests were performed to study the pullout test in loose and dense

sand around the Soil Hook System (SHS) in chamber box , that the up mentioned

system will rotate after the beginning of pullout loading. Raining methods and

vibration method were employed in chamber box to obtain loose and dense

packing sand respectively.

Chapter Four contains the interpretation of the experimental results. The

variations of model ultimate capacity,

with the embedment ratio L/D and

breakout factor in dry loose sand and dense sand are analyzed. Dry sand was

originated from Malaysia sand quarry area, generally having grain sizes between

0.205 to 2.36 mm. It was used as an embedment medium in small and big model

in the wood box. Due to the difficulties in preparing the similar sand sizes, a wide

range of size between 0.07 to 5.01 mm was used as the embedment of small and

big model sizes of Soil Hook System (SHS) in wood box. It was assumed that no

prominence effect on the stress value will be encountered between these two

arrangements. Soil Hook System (SHS) was fabricated blade, joint and their rods

4

that they used as a new anchor in special shape, with a length 290 and 145 mm,

width 100 and 50 mm, which it can be taken into sand and after putting into

balance embedment the rotation begins.

Chapter Five contains the interpretation of the theoretical analysis results.

The new empirical formula of model ultimate capacity,

with the embedment

ratio L/D and

breakout factor in dry loose sand and dense sand were compared

to previous theories in anchor plates. The proposed results will be compared with

previous works such as Murray, Meyerhof and Dickin.

Chapter Six outlines the main conclusions of this research and suggestions

for future work.

1.6 Expected Finding

The expected findings of this research have been identified:

i. Performance of pullout test of Soil Hook System (SHS) in loose and dense

sand

The system is expected that the Soil Hook System (SHS) drives into sand

consisted of loose sand and dense sand, with no excavation of the waterfront

property, thus no holes, no digging, no grouting, no expensive restoration is

required.

ii. Compare of Result in laboratory with previous works

The Compare of result in laboratory and previous works by last researchers will

be conducted with anchor plate results without grouting and development scheme

in loose and dense sand.

iii. Conclusion

This study is successful if it can achieve the research study objectives.

84

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