CONTENTS Acknowledgements i Summary iii Samenvatting v Tableof contents vii 1 Introduction 1 1.1 Scope 1 1.2 Problem definition 2 1.3 Research rationale 3 1.4 Research objective 4 1.5 Methodology 4 1.6 Thesis outline 5 2 Discontinuities: types, origin and properties 7 2.1 Introduction. 7 2.2 The importance of discontinuities 7 2.3 Mechanical properties of rock material 8 2.4 Geological consequences of discontinuity development 15 2.5 Geological definitions of discontinuities 17 2.6 Properties of discontinuities 23 2.7 Discussion and conclusions 25 3 Characterisation of the geometric properties of discontinuities 27 3.1 lntroduction 27 3.2 Geometric discontinuity properties 27 3.3 The value of geometric discontinuity characterisation 34 3.4 Use of discontinuity information by characterisation and classification systems 35 3.5 Current manual methods for collecting discontinuity data 37 3.6 Current remote sensing methods for collecting discontinuity data 39 3.7 Analysis of discontinuity data 44 3.8 Discussion and conclusions 57 4 Assessment of 3-D terrestrial laser scanning 59 4.1 lntroduction 59 4.2 Fundamentals of 3-D terrestrial laser scanning 59 4.3 Performance and specifications 60 4.4 Comparison of laserscan performance and specifications 64 4.5 Sources of error of 3-D laserscan measurements 64 4.6 Operational issues relevant to the scanning of rock faces 66 4.7 Comparison with 3-D photogrammetry 77 4.8 Discussion and conclusions 81 5 Field data acquisition 83 5.1 lntroduction 83 5.2 Data acquisition methodology 83 5.3 Field methods. 83 5.4 Laser scan survey and fieldwork Spain 84 5.5 Laser scan survey Belgium 98 6 Methods for analysing point cloud data 103 6.1 Introduction 103 6.2 Methodologies 103 6.3 Character of point cloud data 104 6.4 2-D gridding as a surface reconstruction technique 107 6.5 3-D surface reconstruction techniques 108 6.6 Point cloud segmentation techniques 113 6.7 Discussion and conclusions 121 7 Extracting discontinuity planes with surface reconstruction 123 7.1 Introduction 123 7.2 Introduction to the surface reconstruction approach 123 7.3 Method 1: Surface reconstruction with an implicit representation 124 7.4 Results of applying surface reconstruction with an implicit representation (Method 1) 131 7.5 Method 2: Surface reconstruction with 2-D gridding using Split-FX software . 148 7.6 Results of surface reconstruction with 2-D gridding using Split-FX software (Method 2) 152 7.7 Discussion and conclusions 153 8 Extracting discontinuity planes with direct segmentation 159 8.1 Introduction 159 8.2 Introduction to the direct segmentation approach 1- 59 8.3 Method 3: Segmentation based on Principal Component Analysis and implemented in Matlab 162 8.4 Results of applying Principal Component Analysis segmentation (Method 3) .169 8.5 Method 4: Segmentation based on Hough transformation and Least-Squares regression and implemented in Point Cloud Mapper (Method 4) 171 8.6 Results of applying Hough transformation and Least-Squares regression segmentation (Method 4) 176 8.7 Discussion and conclusions 178 9 Deriving discontinuity information 181 9.1 Introduction 181 9.2 Methodology 181 9.3 Computation of plane geometry for each discontinuity 181 9.4 Classification into discontinuity sets 183 9.5 Calculating normal set spacing 185 9.6 Computed discontinuity set properties for Site 1: Bellmunt 191 9.7 Computed discontinuity set properties for Site 2: Torroja 202 9.8 Evaluation of the results 213 9.9 Discussion and conclusions 225 10 Conclusions 228 10.1 lntroduction 228 10.2 Conventional rock face mapping versus remote sensing228 10.3 Hypothesis, objectives and methodology 229 10.4 The point cloud processing methods 230 10.5 Verification of the results 230 10.6 Applications and limitations 231 10.7 Concluding remarks 232 Reference 235 Curriculum Citae 245 List of abbreviations 247