SOIL PROPERTIES IN EAST JAVA FOR SITE SUITABILITY ASSESSMENT

GEOSTATISTICAL MODELLING OF

SOIL PROPERTIES IN EAST JAVA FOR SITE SUITABILITY ASSESSMENT

MARELIANDA AL DIANTY

UNIVERSITI SAINS MALAYSIA

2016

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GEOSTATISTICAL MODELLING OF SOIL PROPERTIES IN EAST JAVA FOR SITE SUITABILITY ASSESSMENT

by

MARELIANDA AL DIANTY

Thesis submitted in fulfilment of the requirements for the degree of

Doctor of Philosophy

September 2016

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ACKNOWLEDGMENTS

In the first place, I give thanks to the Almighty Allah SWT for the strength and wisdom to put these words together. Higher appreciation goes to my supervisor, Prof. Ahmad Shukri Yahaya for all your assistance, guidance, support and always believe with me. His insightful reviews of my research were greatly appreciated.

I express my gratitude to my co-Supervisor, Prof. Dr.Fauziah Ahmad for her support and guidance. May Allah SWT richly bless to both of you and family.

This thesis is the result of many hours of hard work and support from family.

I deeply thank to my family, Gusti Amri., Msc, H.Harun Al Rashid, Hj.Susilawati, Densury Al Dian., MBA, dr. Devi Feriani who have supported me throughout educational endeavour. Thank you for the opportunity to pursuing higher education and helping me in financial support. Thank you for the all prayers, take care of my

son and all the encouragement. I owe a lot with you. My blessings and love to my son, Akhtarelgusya Al Dian, I am sorry leave you and I am not beside you.

I would like to express grateful thanks to Dr. Fabio Veronessi (Cranfield University) who has helped me to understand geostatitical modelling with

R software. Thank you for your useful information and references that was valuable for my research. I always disturb you with my entire question.

Sincerely thank and deep appreciation to my entire friend from Iran, Iraq, Nigeria, Philippine, China and of course Malaysia who always support me and encouragement throughout this process more than my friend from my own country.

I would like to thank for my last employer, Huawei Co., Ltd and my team in NTS project 2G/3G. I wish to express biggest also thank to all staffs and all lectures at

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school of civil engineering. Last, special thanks to all cleaning services and securities in civil engineering school and in my hostel who always give me warm greeting and smile when they see me. They call me “Ina” because I am from Indonesia.

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TABLE OF CONTENTS

Page

ACKNOWLEDGMENTS ii

TABLE OF CONTENTS iv

LIST OF TABLES ix

LIST OF FIGURES x

LIST OF ABBREVIATIONS xii

LIST OF SYMBOLS xiii

ABSTRAK xv

ABSTRACT xvii

CHAPTER ONE: INTRODUCTION 1.1 Overview 1

1.1.1 Soil variability and uncertainty 2

1.1.2 Site suitability planning 4

1.2 Geological background 8

1.3 Problem statement 11

1.4 Objective 13

1.5 Scope of study 13

1.6 Structure of thesis 15

CHAPTER TWO: LITERATURE REVIEW 2.1 Introduction 17

2.2 Characteristics of East Java province 18

2.3 Characterization of soil 21

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2.3.1 The importance of some soil engineering properties 22

2.3.2 Soil clay 25

2.3.3 Volcanic ash 27

2.3.4 Residual soil 28

2.4 Statistical and probability distribution in geotechnical 32

2.4.1 Statistics approach 32

2.4.2 Probability distribution techniques 33

2.5 Geostatistics modelling 36

2.5.1 Variogram modelling as tool of spatial autcoerrelation 37

2.5.2 Restricted maximum likelihood (REML) method 42

2.5.3 Characteristics of ordinary kriging 43

2.5.4 Mapping by ordinary kriging 44

2.5.5 Geostatistics in geotechnical 47

2.5.6 Geostatistics in telecommunication network 52

2.6 Land planning and site suitability 53

2.6.1 Site selection in telecommunication network 56

2.6.2 Site telecommunication and the tower 59

2.6.3 Problems in tower construction 62

2.7 Summary 63

CHAPTER THREE: METHODOLOGY 3.1 Introduction 69

3.2 Study area 71

3.2.1 Zoning sites 72

3.3 Data collection 73

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3.3.1 Site survey 75

3.3.2 Soil investigation 75

3.3.2.1 Boring sampling 76

3.3.2.2 Laboratory testing 77

3.4 Selection of soil engineering properties 77

3.4.1 Plasticity index 79

3.4.2 Void ratio and porosity 79

3.4.3 Shear strength 80

3.5 Method of soil characterization 80

3.5.1 ANOVA test 81

3.5.2 Descriptive statistics 82

3.5.3 Engineering classification of soil 82

3.5.4 Probability distribution analysis 84

3.6 Method of gostatistical modelling for site suitability assessment 90

3.6.1 Explanatory data 90

3.6.1.1 Transforming the project string 91

3.6.1.2 Creating interpolating grid 91

3.6.2 Spatial autocorrelation 92

3.6.2.1 Empirical variogram 93

3.6.2.2 Fitting variogram modelling 94

3.6.2.3 Goodness of fit the variogram modelling 96

3.6.2.3.1 Variogram modelling without REML 96

3.6.2.3.2 Variogram modelling with REML 96

3.6.3 Prediction and mapping by ordinary kriging 97

3.6.3.1 Validation and testing of data set 97

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3.6.3.2 The ordinary kriging as a tools of prediction 98

3.6.4 Site suitability assessment method 101

3.7 Summary 106

CHAPTER FOUR: RESULT AND DISCUSSIONS 4.1 Introduction 109

4.2 Development of soil characterization 110

4.2.1 Analysis of variance (ANOVA Test) 110

4.2.2 Descriptive statistics 110

4.2.3 Histogram 115

4.2.4 Engineering classification of soil 117

4.2.4.1 Plasticity chart 118

4.2.4.2 Particle size distribution analysis 118

4.2.5 Probability distribution analysis 124

4.2.6 East Java soil characterization 129

4.3 Development of site suitability assessment 137

4.3.1 Spatial autocorrelation analysis 138

4.3.2 Prediction and mapping 144

4.3.2.1 Prediction result 144

4.3.2.2 Mapping of soil engineering properties 146

4.3.3 Analysis of site suitability assessment 157

CHAPTER FIVE: CONCLUSION AND RECOMMENDATION 5.1 Introduction 166

5.2 Conclusion 166

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5.2.1 Soil characterization of East Java province 166

5.2.2 Modelling spatial autocorrelation of geotechnical 168

5.2.3 Site suitability assessment for site development 169

5.3 Limitation of research 170

5.4 Recommendations 172

REFERENCES 173

APPENDICES

Appendix A : Site information

Appendix B : Soil engineering properties data Appendix C : Zoning sites data

Appendix D : Pdf and Cdf plot of probability distribution analysis Appendix E : Spatial autocorrelation modelling

Appendix F : Script by R software for geostatistical modelling Appendix G : Result of ranking factors and criterion

Appendix H: Standard of soil and sample of soil laboratory testing

LIST OF PUBLICATIONS

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LIST OF TABLES

Page Table 2.1 The comparison of residual soil characterization 31 Table 2.2 Coefficient of variation (COV) of soil engineering

properties

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Table 2.3 Probability distribution for different soil properties 34 Table 2.4 Spatial autocorrelation of soil properties in 0 - 10 cm soil

depth

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Table 2.5 (a) Summary literature review of method using statistical and probability distribution techniques

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Table 2.5 (b) Summary literature review of method using geostatistical modelling

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Table 3.1 ANOVA test formula 81

Table 3.2 Ranking for site development 105

Table 4.1 Analysis of variance (ANOVA) 110

Table 4.2 Descriptive statistics each zone 114

Table 4.3 Normality test by Kolmogorov Smirnov (KS) statistic 124 Table 4.4 Performance indicator result of probability distribution 128 Table 4.5 Spatial autocorrelation with and without robust variogram

modelling

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Table 4.6 Validation of prediction and mapping 145

Table 4.7 Prediction result of soil engineering properties 148

Table 4.8 Ranking of site suitability 161

Table 5.1 Characterization of soil engineering properties based on the zone

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LIST OF FIGURES

Page

Figure 1.1 Site telecommunication defect 4

Figure 1.2 Land use mapping of East Java province 7

Figure 1.3 Geological Map of East Java 10

Figure 1.4 Stratigraphy and structure map of East Java 11 Figure 2.1 Sample of variogram and the three parameter 38

Figure 2.2 Map of site planning and site selection 57

Figure 2.3 Site telecommunication and the facilities 60

Figure 2.4 Green field site 62

Figure 2.5 Fallen tower 63

Figure 3.1 Flowchart of methodology 70

Figure 3.2 Map of East Java Province 72

Figure 3.3 Map of zoning site 74

Figure 3.4 Boring sampling 77

Figure 3.5 Bore log data sheet 78

Figure 3.6 Plasticity chart for the classification of soils 83 Figure 3.7 Grid map and the points of the location telecommunication

sites

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Figure 3.8 Flowchart site suitability assessment 102 Figure 3.9 Integration of topograpy and DEM map of East Java provice 103

Figure 4.1 Histogram of soil engineering properties 116

Figure 4.2 Plot of base soils each zone on plasticity chart 118 Figure 4.3 Particle size distribution of soil at zone 1 119

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Figure 4.4 Particle size distribution of soil at zone 2 120 Figure 4.5 Particle size distribution of soil at zone 3 120 Figure 4.6 Particle size distribution of soil at zone 5 121 Figure 4.7 Particle size distribution of soil at zone 6 122 Figure 4.8 Particle size distribution of soil at zone 7 123 Figure 4.9 Particle size distribution of soil at zone 8 123 Figure 4.10 Cdf plot for plasticity index using the best central fitting

distribution

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Figure 4.11 Pdf plot for plasticity index using the best central fitting distribution

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Figure 4.12 Variogram model of plasticity index by Exponential 141 Figure 4.13 Variogram model of void ratio by Exponential 142

Figure 4.14 Variogram model of porosity by Gaussian 142

Figure 4.15 Variogram model of shear strength by Exponential 153 Figure 4.16 Mapping spatial distribution of plasticity index 154 Figure 4.17 Mapping spatial distribution of void ratio 155 Figure 4.18 Mapping spatial distribution of porosity 155 Figure 4.19 Mapping spatial distribution of shear strength 156

Figure 4.20 Site suitability mapping 160

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LIST OF ABBREVIATIONS

ANOVA One-factor analysis of variance AHP Analytical Hierarchy Process

BTS Base Transmitter System

BSC Base Switching Centre

CDF Cumulative Distribution Function

COV Coefficient of Variation

MLM Maximum Likelihood Method

PDF Probability Distribution Function

REML Residual Maximum Likelihood

RNP Radio Network Planning

RMSE Root Mean Square Error

PA Prediction of Accurancy

IA The Index of Agreement

RMSD Root Mean Square Deviation

Cov Covariance

OK Ordinary Kriging

USCS Unified Soil Classification System

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LIST OF SYMBOLS

C The sill in variogram models

Co The nugget effect in a variogram model

H0 The null hypothesis

H1 The alternative hypothesis

N The size of sample

p-value The probability value

Ak Unknown coefficients

ε(x) Spatially dependent random component

) (x f

a

) (s

µ

H Lag (separating)

Z (x) regionalized variable

γ(h) Semivariance

N Porosity

E Void ratio

R² Coefficient of determination

Nh Number of separating distance

P

O

P Mean value of predicted

O Observes values of predicted

σ

σ

R Pearson product moment correlation

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LL Liquid Limit

PL Plastic Limit

PI Plasticity Index

Wc Water Content

Gs Specific Gravity

γt Unit weight

γd Unit Density

γsat Unit Saturated

ϕ Angle of friction

C Cohesion

τ Shear strength

σn Normal stress

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PEMODELAN GEOSTATISTIK SIFAT TANAH DI JAWA TIMUR UNTUK PENILAIAN KESESUAIAN TAPAK

ABSTRAK

Kepelbagaian spatial mempengaruhi tingkah laku asas dan oleh itu prestasi struktur geoteknikal. Kajian ini telah menjalankan analisis kuantitatif untuk pencirian tapak

dan untuk ramalan sifat kejuruteraan tanah menggunakan statistik dan teknik pemodelan geostatistik yang telah digunakan dalam analisis geoteknikal tetapi

jarang digunakan dalam bidang telekomunikasi. Penyiasatan tapak telah dijalankan berdasarkan prosedur projek telekomunikasi penyokong di wilayah Jawa Timur, Indonesia. Petunjuk kesesuaian bagi projek Jawa Timur adalah empat asas ciri-ciri kejuruteraan tanah iaitu indeks keplastikan, nisbah lompang, keliangan dan kekuatan ricih. Tanah Jawa Timur yang berkaitan dengan asas projek telekomunikasi mempunyai keplastikan yang kebanyakannya tinggi. Empat petunjuk kesesuaian telah digunakan dalam ramalan dan pemetaan. Corak spatial indikator ini digunakan untuk mengenal pasti kawasan-kawasan yang mempunyai ciri-ciri yang sesuai untuk pembinaan. Hasil daripada autokorelasi spatial telah menunjukkan bahawa model variogram dengan penganggar REML lebih sesuai untuk ramalan dan pemetaan berbanding dengan model tanpa REML. Penyelidikan ini peta ramalan dengan resolusi 1 km² grid terhadap 73 tapak di lapan zon yang berbeza. Penilaian pemetaan tapak kesesuaian dijalankan berdasarkan penglihatan, topografi, penggunaan tanah dan ciri tanah, menggunakan proses analisis hierarki (AHP) untuk menentukan kepentingan relatif semua faktor-faktor yang dipilih. Hasil penilaian kesesuaian tapak menunjukkan bahawa Zon 2, Zon 3, Zon 4 dan Zon 8 dapat dikenal pasti

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sebagai kawasan yang sesuai manakala Zon 1, Zon 5, Zon 6 dan Zon 7 dapat dikenal pasti sebagai kawasan yang tidak sesuai untuk pembangunan. Pemodelan geostatistik menggunakan 'kriging' biasa telah berjaya digunakan untuk mencirikan sifat kejuruteraan tanah di setiap zon. Teknik ini boleh digunakan sebagai alat diagnostik untuk mengenal pasti sifat-sifat kejuruteraan tanah di tapak semasa fasa perancangan awal. Keputusan menunjukkan bahawa kaedah ini boleh digunakan untuk membuat keputusan mengenai kesesuaian tapak telekomunikasi walaupun dengan set data yang lebih kecil. Prosedur kajian ini juga boleh digunakan untuk menyediakan panduan yang lebih baik dalam mengutamakan zon untuk pembangunan bidang telekomunikasi. Tambahan pula, kaedah ini menawarkan pendekatan yang lebih dipercayai dan bermaklumat yang boleh digunakan dalam membuat keputusan untuk perancangan tanah selamat dan menjimatkan untuk wilayah Jawa Timur.

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GEOSTATISTICAL MODELLING OF SOIL PROPERTIES IN EAST JAVA FOR SITE SUITABILITY ASSESSMENT

ABSTRACT

Spatial variability influences the behaviour of foundation and therefore the performance of geotechnical structures. This research has carried out a quantitative analysis for site characterization and for prediction of soil engineering

properties using statistics and geostatistical modelling techniques that are already used in geotechnical analyses but are rarely applied in the field of

telecommunications. Site investigations have been carried out based on the procedures of telecommunication projects proponent in East Java province,

Indonesia. The indicators of suitability for the East Java projects were the four elementary soil engineering properties namely plasticity index, void ratio, porosity and shear strength. The soil of East Java associated with the foundation of telecommunication projects were mainly high plasticity. The four indicators of suitability were used in the prediction and mapping. The spatial pattern of these indicators we used to identify the areas that have suitable characteristics for construction. Results from spatial autocorrelation have shown that the variogram modelling by REML estimator to be more acceptable for prediction and mapping in comparison to modelling without REML. This research produced prediction maps with a resolution of 1 km² grids over 73 sites at eight different zones. The evaluation of site suitability mapping was carried out based on visibility, topography, land cover

and soil properties, using the analytical hierarchy process (AHP) in order to determine the relative importance of all the selected factors. The result of site

suitability assessment indicate that at Zone 2, Zone 3, Zone 4 and Zone 8 could be

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identified as suitable areas while Zone 1, Zone 5, Zone 6 and Zone 7 could be

identified as unsuitable areas for development. Geostatistical modelling using the ordinary kriging has been successfully used to characterize soil engineering

properties in each zone. This technique could be used as a diagnostic tool in order to identify the engineering properties of soils at site during the initial planning phase.

The results indicate that this method could decide on the suitability a telecommunication site even with a smaller dataset. The procedures of this research

could also be used to provide better guidance in prioritizing zones for site development. Furthermore, they offer a more reliable and informative approach

that may be applied for in decision-making for the safe and economical land planning for the province of East Java.

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1 CHAPTER ONE

INTRODUCTION

1.1 Overview

The choice of foundation type largely depends on the results of site investigations and laboratory tests on local soils and rocks. Soil engineering

properties are the important items in the analysis of site conditions and structural foundation such as practiced in the telecommunication towers construction activity.

Basic elementary soil properties, including specific gravity, moisture content, dry

density, wet density, and plasticity limits (e.g., liquid limits, plastic and limits), may eventually contribute to the decision making process regarding the suitability of

a site. However, the relevant geotechnical properties like shear strength and compressibility would be the primary quantities used for designing foundations.

Thus, the analysis of elementary soil engineering properties can be significant to land and site management, especially for the telecommunications network projects.

New telecommunication sites and its facilities are needed when telecommunication providers initiate coverage in a geographic area. These new sites

should supplement the inadequate coverage from existing base stations, or the inadequate capacity of existing base stations that no longer capable of handling the number of users to be serviced. The planning for site telecommunications and all

wireless telecommunication facilities, such as towers, shelters, base stations, feeders, and antennas, should correspond to the current update of the community’s comprehensive plan. A comprehensive plan outlines the vision of a community for the future, areas for resource conservation, and targeted areas for growth and

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development. However, towers are being proposed by companies that do not have

immediate plans for antenna installation (towers built on speculation) (Carpenter et al., 2001). Therefore, site suitability planning needed to consider the systematic assessment of land, water potential, and alternatives for land use.

This site suitability planning can be used any construction for future not only telecommunication network sites.

1.1.1 Soil variability and uncertainty

Soil is a unique and natural engineering material with different physical properties. Its uniqueness is due to its variability and how it is formed the continuous processes of the environment that alter it (Uzielli et al., 2007; Adhikari et al., 2012;

Rahardjo et al., 2012). Even for the same soil type, the nature of soils is not identical because soil properties vary from site to site. Variability is not only defined with respect to time or location, but is also represented by a frequency distribution that

shows the variation in a characteristic of interest over time or across a population (Frey and Rhodes, 1999). Soil is modified continuously by different stresses,

weathering, chemical reactions, introduction of new substances, and, in some cases, human intervention (e.g., soil improvement, excavation, filling). Variability in soil properties are often caused by small changes in topography that affect the transport and storage of water across and within the soil profile (Brady and Weil, 2002).

The uncertainties in soil properties inherent in the quality and quantity of soil samples, characteristics of the testing device, and operator’s experience may have a significant effect on the measured geotechnical properties. These uncertainties

should be recognized and quantified to adequately and logically determine the appropriate parameters for engineering analysis and design. Analysing

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the variability and uncertainty of engineering properties to help in the speedy judgment of soil condition at any development site prior to commencement of construction is necessary to minimize the volume of work and the accompanying cost involved in determining all engineering properties required before deciding on the foundation design parameters.

The inherent variation of soils from one location to another is called spatial variability. Statistical and geostatistical analysis can determine the spatial variability of soil properties from a data set in a more logical and accurate manner than otherwise determined (Baecher, 1987; Uzielli et al., 2007; Akbas and Kulhawy, 2010). When dealing with different uncertainties related to soil properties, the use of those stochastic methods generates better geotechnical designs by accurately assessing the influence of spatial variability of different soil properties on structural behavior. This process is also achievable through the use of spatial statistical structures. When these methods are used to analyze the spatial variability of soil properties, they can quantify unknown soil property variations at a site, offer better estimates for unsampled locations, and provide valuable information to systematically treat the sources of uncertainty of soil property measurements in reliability analyses. Therefore, statistical and geostatistical modeling are major contributors to spatial variability analysis in geotechnical engineering.

1.1.2 Site suitability planning

The planning on site suitability of every construction is highly required, such as in telecommunication network sites. A continuous demand for telecommunication technology leads to its rapid evolution. Currently, the new telecommunication industry has created new business imperatives for Telecommunication Company and

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its strength has improved the company’s ability to influence industry trends. As changes in technologies have occurred, many operators of the companies are competing with each other to build telecommunication sites. Every years one operators can build 13,000 new tower telecommunication. Nowdays, around 600,000 of tower telecommunication was already build in Indonesia.

Numerous problems arise during the implementation of telecommunication site construction such as the issues of poor examination of groundwork and pit, such as pit dimensions, soil appearance, soil moisture, layer thickness, soil density, and slope stability. Figure 1.1 shows the poor quality of the pit that endangers slope stability on the soil. Those problems as well as tower failures can be avoided if the soil properties are properly studied, and soil exploration results are correctly understood and intelligently applied to the design as well as construction of earthworks and structural foundations (Mhaske and Choudhury, 2009).

Figure 1.1: Site telecommunication defect

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East Java province was used as study area which is the first national region that going to launch a new telecommunications operator which have many issues during

the implementation. This province covers total area of 47902.7679 Km² and has a population close to 40 millions, making East Java as the second most populated

province in Java Island. East Java has strategic planning included the issue of the development of strategic infrastructure such as transportation, energy and

telecommunications. It is explained in spatial and land use planning of East Java province nombor 5 year of 2012 about strategic provincial spatial planning year of

2012 - 2031 (National Coordinator for Survey and Mapping Agency of Republic Indonesia, 2012).

Topographic conditions of East Java province indicate a large forest potential.

Forest pose agricultural potential as source of sufficient water, which flows throughout the year and can be used for irrigation. This district is considered as a district that have many volcanoes. Volcanoes and large rivers serve as means of spreading nutrient-rich substances resulting from volcanic eruptions and thus contribute to increased soil fertility. Several volcanoes which are still active include Mount Kelud, Mount Merapi and Mount Raung. In addition, the Bengawan Solo River, Brantas River, Solo River, Madiun River, and Konto River are all responsible

for the translocation of fertile soil. Mreover, the southern part of East Java and the Madura Island often experience water related problems. In these regions, the soils

are drier and barren, in contrast to the condition in the west and central parts of East Java where soils are more fertile (Syafitri, 2012). Hence, the variability of soil

engineering around East Java province is considered high because of the variation of material.