Development of an SPI-Based Curtain-Grouting Design Framework Incorporating Rock Discontinuity and Hydrogeological Characteristics in South Korea = 불연속면 및 수리지질 특성을 반영한 SPI 기반 차수 그라우팅 설계 프레임워크 개발

다국어 초록 (Multilingual Abstract)

This dissertation investigates the groutability of dam foundation rock masses through an integrated analysis of hydrogeological parameters, discontinuity characteristics, and grout take, with the overarching goal of establishing a quantitative, data-driven framework for grouting design and evaluation. Recognizing the limitations of empirically based grouting practices traditionally employed in Korea, the research advances the foundation treatment process from experience-oriented decision-making toward scientifically grounded, correlation-based methodologies. The approach combines a comprehensive literature review, multi-site field data analysis, and statistical validation using datasets from fourteen dam sites across South Korea. In Chapter 2, international and domestic research trends on groutability prediction are systematically reviewed. The analysis reveals consistent relationships among key indices: grout take showed negative correlations with Rock Quality Designation (RQD), Q-value and Geological Strength Index (GSI) and positive correlations with Lugeon value (Lu) and Secondary Permeability Index (SPI). Among these, SPI demonstrates the most robust predictive capability for assessing rock permeability and injectability, and its classification scheme provides a rational basis for foundation grouting design. Chapter 3 extends this framework to empirical application using data from 182 boreholes and 393 water pressure tests across fourteen dam foundations. Correlation analyses were first conducted to examine the relationships among hydrogeological and structural parameters with grout take. Principal component analysis (PCA) was then conducted to extract the factors primarily contributing to grout intake. Based on this analytical insight, an SPI-oriented grouting design framework was formulated and subsequently validated against measured curtain-grouting performance, demonstrating its utility as a predictive and planning tool for foundation treatment. Chapter 4 further explores lithology-dependent variations in groutability using borehole and hydraulic test data from five representative dam foundations underlain by granitic gneiss, mica schist, hornfels, granite porphyry, and granite. Statistically significant negative correlations were consistently observed between RQD and hydrogeological indices (Lu and SPI), with SPI once again emerging as the most reliable indicator of grout take. The results demonstrate that lithological variability exerts a substantial influence on the magnitude and nature of these correlations. Accordingly, a new set of evaluation indices based on the RQD–SPI relationship is proposed to establish a systematic and transferable framework for dam foundation grouting under diverse geological conditions. Collectively, the findings presented in this dissertation provides a quantitative foundation for grout design in rock masses and advances understanding of the link between discontinuity development and secondary permeability. This framework enhances prediction accuracy, reduces uncertainty, and strengthens the theoretical and practical basis for foundation treatment in dam engineering.

목차 (Table of Contents)

• 1. BACKGROUND AND SIGNIFICANCE 17
• Overview 17
• Research Rationale and Objectives 20
• 2. RENDS IN PREDICTING GROUTABILITY BASED ON CORRELATION ANALYSIS BETWEEN HYDROGEOLOGICAL AND ROCK ENGINEERING INDICES: A REVIEW 23
• Introduction 23
• Hydrogeological Indices for Predicting Grout Take 25
• Lugeon Value 25
• Secondary Permeability Index 26
• Rock Engineering Indices for Predicting Grout Take 29
• Rock Quality Designation 29
• Q-value 30
• Geological Strength Index 31
• International Case Studies on Predicting Grout Take 33
• Mut Dam 33
• Ostur Dam 38
• De Hoop Dam 40
• Implications 44
• 3. GROUTING IMPROVEMENT THROUGH CORRELATION ANALYSIS OF HYDROGEOLOGY AND DISCONTINUITY FACTORS IN A JOINTED ROCK-MASS 46
• Introduction 46
• Methodology 48
• Study Area and Methodology 48
• Hydrogeological and Discontinuity Parameters 51
• Correlation Analysis 55
• Results and Discussion 56
• Trend Analysis of Parameter Variations with Depth 56
• Correlation Analysis among Parameters 58
• Multivariate and Principal Component Analysis 60
• Correlation Analysis between RQD and SPI 64
• Correlation Analysis Between Parameters and Grout Take 65
• Validation of Grouting Plan 73
• Implications 78
• 4. DEVELOPMENT OF EVALUATION INDICES FOR DAM-FOUNDATION GROUTING BASED ON CORRELATION ANALYSIS BETWEEN DISCONTINUITY AND HYDROGEOLOGICAL PARAMETERS ACROSS ROCK TYPES 80
• Introduction 80
• Methodology 83
• Study Area and Geological Characteristics 83
• Discontinuity and Hydrogeological Parameters 87
• Results and Discussion 91
• Analysis of Parameter Variation Trends by Rock Type 91
• Correlation Analysis among Parameters 99
• Multivariate and Principal Component Analysis 102
• Correlation Analysis between RQD and SPI 114
• Implications 118
• 5. CONCLUDING REMARKS 120
• Chapter 2: Trends in Predicting Groutability Based on Correlation Analysis between Hydrogeological and Rock Engineering Indices: A Review 122
• Chapter 3: Grouting Improvement through Correlation Analysis of Hydrogeology and Discontinuity Factors in a Jointed Rock-Mass 123
• Chapter 4: Development of Evaluation Indices for Dam-Foundation Grouting Based on Correlation Analysis between Discontinuity and Hydrogeological Parameters across Rock Types 123
• Future direction 124
• LIST OF REFERENCES 126