Description
Excavation is an important segment of foundation engineering (e.g., in the construction of the foundations or basements of high-rise buildings, underground oil tanks, or subways). However, the excavation knowledge introduced in most books on foundation engineering is too simple to handle actual excavation analysis and design. Moreover, with economic development and urbanization, excavations go deeper and are larger in scale. These conditions require elaborate analysis, design methods and construction technologies.
This book is aimed at both theoretical explication and practical application. From basic to advanced, this book attempts to achieve theoretical rigor and consistency. Each chapter is followed by a problem set so that the book can be readily taught at senior undergraduate and graduate levels. The solution to the problems at the end of the chapters can be found on the website (http://www.ct.ntust.edu.tw/ou/). On the other hand, the analysis methods introduced in the book can be used in actual analysis and design as they contain the most up-to-date knowledge. Therefore, this book is suitable for teachers who teach foundation engineering and/or deep excavation courses and engineers who are engaged in excavation analysis and design.
Table of Contents
1 Introduction to the analysis and design of excavations
1.1 Geological investigation and soil tests
1.2 Conditions of the adjacent properties
1.3 Confirmation of the conditions of an excavation site
1.4 Design criteria
1.5 Collecting case histories of the nearby excavations
1.6 Auxiliary methods
1.7 Excavation analyses
1.8 Layout of the strutting system
1.9 Monitoring system
1.10 Protection of neighboring properties
2 Engineering properties of soils and geotechnical analysis
2.1 Introduction
2.2 Engineering properties
2.3 Principle of effective stress
2.4 Failure of soils
2.5 Characteristics of drained shear strength of soils
2.6 Characteristics of undrained shear strength of saturated cohesive soils
2.7 Undrained shear strength of unsaturated cohesive soils
2.8 Deformation characteristics of soils
2.9 Geotechnical analysis method
2.10 Stress paths in excavations
Problems
3 Excavation methods and lateral supporting systems
3.1 Introduction
3.2 Excavation methods
3.3 Retaining walls
3.4 Strutting systems
3.5 Selection of a retaining strut system
3.6 Construction of the TNEC project
Problems
4 Lateral earth pressure
4.1 Introduction
4.2 Lateral earth pressure at rest
4.3 Rankine’s earth pressure theory
4.4 Coulomb’s earth pressure theory
4.5 General discussion of various earth pressure theories
4.6 Earth pressure for design
Problems
5 Stability analysis
5.1 Introduction
5.2 Types of factors of safety
5.3 Base shear failure
5.4 Free earth support method and fixed earth support method
5.5 Base shear failure of strutted walls
5.6 General discussion of analysis methods of base shear failure
5.7 Case study of base shear failure
5.8 Base shear failure of cantilever walls
5.9 Upheaval failure
5.10 Sand boiling
5.11 Case study of sand boiling
Problems
6 Stress and deformation analysis: simplified method
6.1 Introduction
6.2 Analysis of settlement induced by the construction of diaphragm walls
6.3 Characteristics of wall movement induced by excavation
6.4 Characteristics of ground movement induced by excavation
6.5 Characteristics of excavation bottom movement induced by excavation
6.6 Time-dependent movement
6.7 Analysis of wall movements induced by excavation
6.8 Analysis of surface settlements induced by excavation
6.9 Three-dimensional excavation behavior
6.10 Stress analysis
Problems
7 Stress and deformation analysis: beam on elastic foundation method
7.1 Introduction
7.2 Basic principles
7.3 Formulation
7.4 Simulation of construction sequence
7.5 Estimation of coefficient of subgrade reaction
7.6 Estimation of coefficient of the at-rest earth pressure
7.7 Estimation of structural parameters
7.8 Direct analysis and back analysis
7.9 Computation of ground surface settlement
7.10 Limitations of beam on elastic foundation method
Problems
8 Stress and deformation analysis: finite element method
8.1 Introduction
8.2 Framework and principles
8.3 Effective stress analysis and total stress analysis
8.4 Commonly used soil models and related parameters
8.5 Determination of soil parameters
8.6 Determination of initial stresses
8.7 Structural material models and related parameters
8.8 Mesh generation
8.9 Plane strain analysis and 3D analysis
8.10 Finite element stability analysis
8.11 FEA procedure
Problems
9 Dewatering in excavations
9.1 Introduction
9.2 Goals of dewatering
9.3 Methods of dewatering
9.4 Well theory
9.5 Pumping tests
9.6 Dewatering plan for an excavation
9.7 Dewatering and ground settlement
Problems
10 Design of retaining structural components
10.1 Introduction
10.2 Design methods and factors of safety
10.3 Retaining walls
10.4 Structural components in braced excavations
10.5 Strut systems
10.6 Structural components in anchored excavations
10.7 Anchor systems
10.8 Tests of anchors
Problem
11 Excavation and protection of adjacent buildings
11.1 Introduction
11.2 Allowable settlement of buildings
11.3 Assessment of building safety and design of protection measures
11.4 Adjustment of construction sequence
11.5 Strengthening the strut-retaining system
11.6 Soil improvement
11.7 Cross walls
11.8 Buttress walls
11.9 Micro piles
11.10 Underpinning
11.11 Construction defects and remedial measures
11.12 Building rectification methods
Problems
12 Monitoring systems
12.1 Introduction
12.2 Elements of a monitoring system
12.3 Principles of strain gauges
12.4 Measurement of movement and tilt
12.5 Measurement of stress and force
12.6 Measurement of water pressure and groundwater level
12.7 Other measurement objects
12.8 Plan of monitoring systems
12.9 Application of monitoring systems
Problems
Appendix A: Conversion factors
Appendix B: Soil properties at the TNEC excavation site
Appendix C: Definition of plane strain
