Handbook of Geotechnical Investigation and Design Tables

Burt Look is a practicing consulting geotechnical engineer. He obtained his first degree in Civil Engineering and his Master’s degree in Soil Mechanics and Engineering Seismology at the Imperial College of Science and Technology, University of London. He completed his PhD at The University of Queensland.and he is a Fellow of the Institute of Engineers, Australia. He is currently a Geotechnical Practice Leader at Sinclair Knight Merz. He was formerly a Principal and the Geotechnical Knowledge and Service Delivery Leader at Connell Wagner (now Aurecon). His key role is in the planning and assessment of geotechnical investigations and its implementation into the design. He lectures short courses in industry for Education Engineers Australia to practicing professionals. His research is focused on applications in industry practice and he supervises theses at both The University of Queensland and Queensland University of Technology, Australia.

1 Site investigation
1.1 Geotechnical engineer
1.2 Developing models
1.3 Geotechnical involvement
1.4 Geotechnical requirements for the different project phases
1.5 Relevance of scale
1.6 Planning of site investigation
1.7 Planning of groundwater investigation
1.8 Level of investigation
1.9 Planning prior to ground truthing
1.10 Extent of investigation
1.11 Site investigation for driven piles to rock
1.12 Volume sampled
1.13 Relative risk ranking of developments
1.14 Sample amount
1.15 Sample disturbance
1.16 Sample size
1.17 Quality of site investigation
1.18 Costing of investigation
1.19 Site investigation costs
1.20 The business of site investigation


2 Soil classification and description
2.1 Important information
2.2 Soil borehole record
2.3 Borehole record in the field
2.4 Drilling information
2.5 Water level
2.6 Soil type
2.7 Major and minor components of soil descriptions
2.8 Field guide identification
2.9 Sedimentation test
2.10 Unified soil classification
2.11 Particle description
2.12 Gradings
2.13 Colour
2.14 Soil plasticity
2.15 Atterberg limits
2.16 Consistency of cohesive soils
2.17 Consistency of non-cohesive soils
2.18 Structure
2.19 Moisture content
2.20 Origin
2.21 Comparison of characteristics between residual and transported soils
2.22 Classification of residual soils by its primary mode of occurrence


3 Rock classification
3.1 Important rock information
3.2 Rock description
3.3 Field rock core log
3.4 Drilling information
3.5 Rock weathering
3.6 Colour
3.7 Rock structure
3.8 Rock quality designation
3.9 Rock strength
3.10 Rock hardness
3.11 Discontinuity scale effects
3.12 Rock defects spacing
3.13 Rock defects description
3.14 Rock defect symbols
3.15 Sedimentary and pyroclastic rock types
3.16 Metamorphic and igneous rock types


4 Field sampling and testing
4.1 Types of sampling
4.2 Boring types
4.3 Field sampling
4.4 Field testing
4.5 Comparison of in situ tests
4.6 Standard penetration test in soils
4.7 Standard penetration test in rock
4.8 Overburden correction factors to SPT result
4.9 Equipment and borehole correction factors for SPT result
4.10 Cone penetration test
4.11 Dilatometer
4.12 Pressuremeter test
4.13 Vane shear
4.14 Vane shear correction factor
4.15 Dynamic cone penetrometer tests
4.16 Light weight falling deflectometer
4.17 Clegg impact soil tester
4.18 Surface strength from site walk over
4.19 Surface strength from vehicle drive over
4.20 Operation of earth moving plant


5 Soil strength parameters from classification and testing
5.1 Errors in measurement
5.2 Clay strength from pocket penetrometer
5.3 Clay strength from SPT data
5.4 Residual soils strength from SPT data
5.5 Clean sand strength from SPT data
5.6 Fine and coarse sand strength from SPT data
5.7 Effect of aging
5.8 Effect of angularity and grading on strength
5.9 Critical state angles in sands
5.10 Peak and critical state angles in sands
5.11 Strength parameters from DCP data
5.12 CBR value from soil classification test
5.13 CBR value from DCP data
5.14 CBR values from DCP data specific to soil type
5.15 Allowable bearing capacity from DCP tests
5.16 Soil classification from cone penetration tests
5.17 Soil type from friction ratios
5.18 Clay parameters from cone penetration tests
5.19 Clay strength from cone penetration tests
5.20 Simplified sand strength assessment from cone penetration tests
5.21 Soil type from Dilatometer test
5.22 Lateral soil pressure from Dilatometer test
5.23 Soil strength of sand from Dilatometer test
5.24 Clay strength from effective overburden
5.25 Variation of undrained strength ratio


6 Rock strength parameters from classification and testing
6.1 Rock strength
6.2 Typical refusal levels of drilling rig
6.3 Parameters from drilling rig used
6.4 Field evaluation of rock strength
6.5 Rock strength from point load index values
6.6 Strength from Schmidt hammer
6.7 Strength assessment from RQD
6.8 Relative change in strength between rock weathering grades
6.9 Parameters from rock weathering
6.10 Rock classification
6.11 Rock strength from slope stability
6.12 Typical field geologist’s rock strength
6.13 Typical engineering geology rock strengths
6.14 Relative strength – combined considerations
6.15 Parameters from rock type
6.16 Rock durability
6.17 Material use


7 Soil properties and state of the soil
7.1 Soil behaviour
7.2 State of the soil
7.3 Soil weight
7.4 Significance of colour
7.5 Plasticity characteristics of common clay minerals
7.6 Weighted plasticity index
7.7 Effect of grading
7.8 Effective friction of granular soils
7.9 Effective strength of cohesive soils
7.10 Over-consolidation ratio
7.11 Pre-consolidation stress from cone penetration testing
7.12 Pre-consolidation stress from Dilatometer
7.13 Pre-consolidation stress from shear wave velocity
7.14 Over-consolidation ratio from Dilatometer
7.15 Lateral soil pressure from Dilatometer test
7.16 Over consolidation ratio from undrained strength ratio and friction angles
7.17 Over-consolidation ratio from undrained strength ratio
7.18 Sign posts along the soil suction pF scale
7.19 Soil suction values for different materials
7.20 Capillary rise
7.21 Equilibrium soil suctions in Australia
7.22 Effect of climate on soil suction change
7.23 Effect of climate on active zones
7.24 Compaction concepts
7.25 Effect of compaction on suction


8 Permeability and its influence
8.1 Typical values of permeability
8.2 Permeability equivalents
8.3 Comparison of permeability with various engineering materials
8.4 Permeability based on grain size
8.5 Permeability based on soil classification
8.6 Permeability from dissipation tests
8.7 Effect of pressure on permeability
8.8 Effect of fines on permeability
8.9 Permeability of compacted clays
8.10 Effect of moulding water content on permeability
8.11 Permeability of untreated and asphalt treated aggregates
8.12 Dewatering methods applicable to various soils
8.13 Radius of influence for drawdown
8.14 Typical hydrological values
8.15 Relationship between coefficients of permeability and consolidation
8.16 Typical values of coefficient of consolidation
8.17 Variation of coefficient of consolidation with liquid limit
8.18 Coefficient of consolidation from dissipation tests
8.19 Time factors for consolidation
8.20 Time required for drainage of deposits
8.21 Estimation of permeability of rock
8.22 Effect of joints on rock permeability
8.23 Lugeon tests in rock


9 Rock properties
9.1 General engineering properties of common rocks
9.2 Rock weight
9.3 Rock minerals
9.4 Silica in igneous rocks
9.5 Hardness scale
9.6 Rock hardness
9.7 Influence of properties on bored pile
9.8 Mudstone–shale classification based on mineral proportion
9.9 Relative change in rock property due to discontinuity
9.10 Rock strength due to failure angle
9.11 Rock defects and rock quality designation
9.12 Rock laboratory to field strength
9.13 Rock shear strength and friction angles of specific materials
9.14 Rock shear strength from RQD values
9.15 Rock shear strength and friction angles based on geologic origin
9.16 Friction angles of rocks joints
9.17 Asperity rock friction angles
9.18 Shear strength of filled joints


10 Material and testing variability with risk assessment
10.1 Variability of materials
10.2 Variability of soils
10.3 Variability of in-situ tests
10.4 Soil variability from laboratory testing
10.5 Guidelines for inherent soil variability
10.6 Compaction testing
10.7 Guidelines for compaction control testing
10.8 Subgrade and road material variability
10.9 Deflection testing for pavements
10.10 Distribution functions
10.11 Distribution functions for rock strength
10.12 Effect of distribution functions on rock strength
10.13 CBR values for a linear (transportation) project
10.14 Point load index values for a vertical linear (bridge) project
10.15 Variability in design and construction process 1
10.16 Prediction variability for experts compared with industry practice
10.17 Variability in selecting design values
10.18 Tolerable risk for new and existing slopes
10.19 Probability of failures of rock slopes
10.20 Qualitative risk analysis
10.21 Qualitative measure of likelihood
10.22 Qualitative measure of consequences to property
10.23 Risk level implications
10.24 Acceptable probability of slope failures
10.25 Probabilities of failure based on lognormal distribution
10.26 Project reliability
10.27 Road reliability values
10.28 Reliability index
10.29 Concrete quality
10.30 Soil property variation for reliability calibration
10.31 Testing, spatial and temporal variation


11 Deformation parameters
11.1 Modulus definitions
11.2 Small strain shear modulus
11.3 Comparison of small to large strain modulus
11.4 Strain levels for various applications
11.5 Modulus applications
11.6 Typical values for elastic parameters
11.7 Elastic parameters of various soils
11.8 Typical values for coefficient of volume compressibility
11.9 Coefficient of volume compressibility derived from SPT
11.10 Deformation parameters from CPT results
11.11 Drained soil modulus from cone penetration tests
11.12 Soil modulus in clays from SPT values
11.13 Drained modulus of clays based on strength and plasticity
11.14 Undrained modulus of clays for varying over consolidation ratios
11.15 Soil modulus from SPT values and plasticity index
11.16 Short and long term modulus
11.17 Poisson ratio in soils
11.18 Resilient modulus
11.19 Typical rock deformation parameters
11.20 Rock deformation parameters
11.21 Rock mass modulus derived from the intact rock modulus
11.22 Modulus ratio based on open and closed joints
11.23 Rock modulus from rock mass ratings
11.24 Poisson ratio in rock
11.25 Significance of modulus


12 Earthworks
12.1 Earthworks issues
12.2 Excavatability
12.3 Excavation requirements
12.4 Excavation characteristics
12.5 Excavatability assessment
12.6 Excavatability assessment for heavy ripping equipment
12.7 Excavatability assessment based on seismic wave velocities
12.8 Excavatability production rates
12.9 Diggability index
12.10 Diggability classification
12.11 Excavations in rock
12.12 Rippability rating chart
12.13 Bulking factors
12.14 Practical maximum layer thickness
12.15 Large compaction equipment
12.16 Ease of compaction
12.17 Compaction requirements for various applications
12.18 Required compaction
12.19 Comparison of relative compaction and relative density
12.20 Field characteristics of materials used in earthworks
12.21 Typical compaction characteristics of materials used in earthworks
12.22 Suitability of compaction plant
12.23 Typical lift thickness
12.24 Maximum size of equipment based on permissible vibration level
12.25 Compaction required for different height of fill
12.26 Typical compaction test results
12.27 Field compaction testing
12.28 Standard versus modified compaction
12.29 Application of standard and modified compaction
12.30 Effect of excess stones


13 Subgrades and pavements
13.1 Types of subgrades
13.2 CBR laboratory model
13.3 CBR tests in subgrade assessment
13.4 CBR reporting
13.5 CBR soaked and unsoaked tests
13.6 Subgrade strength classification
13.7 Damage from volumetrically active clays
13.8 Subgrade volume change classification
13.9 Minimising subgrade volume change
13.10 Subgrade moisture content
13.11 Subgrade strength correction factors to soaked CBR
13.12 Approximate CBR of clay subgrade
13.13 Typical values of subgrade CBR
13.14 Properties of mechanically stable gradings
13.15 Soil stabilisation with additives
13.16 Soil stabilisation with cement
13.17 Effect of cement soil stabilisation
13.18 Soil stabilisation with lime
13.19 Lime stabilisation rules of thumb
13.20 Soil stabilisation with bitumen
13.21 Pavement strength for gravels
13.22 CBR values for pavements
13.23 CBR swell in pavements
13.24 Plasticity index properties of pavement materials
13.25 Typical CBR values of pavement materials
13.26 Typical values of pavement modulus
13.27 Typical values of existing pavement modulus
13.28 Equivalent modulus of sub bases for normal base material
13.29 Equivalent modulus of sub bases for high standard base material
13.30 Typical relationship of modulus with subgrade CBR
13.31 Typical relationship of modulus with base course CBR
13.32 Aggregate loss to weak subgrades
13.33 Elastic modulus of asphalt
13.34 Poisson ratio
13.35 Specific gravity


14 Slopes
14.1 Slope measurement
14.2 Factors causing slope movements
14.3 Causes of slope failure
14.4 Factors of safety for slopes
14.5 Factor of safety for different input assumptions
14.6 Comparison of factor of safety with probability if failure
14.7 Factors of safety for new slopes
14.8 Factors of safety for existing slopes
14.9 Risk to life
14.10 Economic and environmental risk
14.11 Cut slopes
14.12 Fill slopes
14.13 Factors of safety for dam walls
14.14 Typical slopes for low height dam walls
14.15 Effect of height on slopes for low height dam walls
14.16 Design elements of a dam walls
14.17 Stable slopes of levees and canals
14.18 Slopes for revetments
14.19 Crest levels based on revetment type
14.20 Crest levels based on revetment slope
14.21 Stable slopes underwater
14.22 Side slopes for canals in different materials
14.23 Seismic slope stability
14.24 Stable topsoil slopes
14.25 Design of slopes in rock cuttings and embankments
14.26 Factors affecting the stability of rock slopes
14.27 Rock falls
14.28 Coefficient of restitution
14.29 Rock cut stabilization measures
14.30 Rock trap ditch
14.31 Trenching


15 Terrain assessment, drainage and erosion
15.1 Terrain evaluation
15.2 Scale effects in interpretation of aerial photos
15.3 Development grades
15.4 Equivalent gradients for construction equipment
15.5 Development procedures
15.6 Terrain categories
15.7 Landslide classification
15.8 Landslide velocity scales
15.9 Slope erodibility
15.10 Erodibility hierarchy
15.11 Soil erosion
15.12 Soil dispersivity
15.13 Erosion thresholds
15.14 Sediment loss from linear vs. concave slopes
15.15 Typical erosion velocities based on material
15.16 Typical erosion velocities based on depth of flow
15.17 Erosion control
15.18 Benching of slopes
15.19 Subsurface drain designs
15.20 Subsurface drains based on soil types
15.21 Open channel seepages
15.22 Comparison between open channel flows and seepages through soils
15.23 Drainage measures factors of safety
15.24 Aggregate drains
15.25 Aggregate drainage properties
15.26 Discharge capacity of stone filled drains
15.27 Slopes for chimney drains
15.28 Drainage blankets
15.29 Resistance to piping
15.30 Soil filters
15.31 Seepage loss through earth dams
15.32 Clay blanket thicknesses


16 Geosynthetics
16.1 Type of geosynthetics
16.2 Geosynthetic properties
16.3 Geosynthetic functions
16.4 Leakage rates
16.5 Static puncture resistance of geotextiles
16.6 Construction survivability ratings
16.7 Physical property requirements
16.8 Robustness classification using the G– rating
16.9 Geotextile durability for filters, drains and seals
16.10 Geotextile durability for ground conditions and construction equipment
16.11 Geotextile durability for cover material and construction equipment
16.12 Robustness geotextile specifications based on strength class
16.13 Establishing geotextile strength class
16.14 Establishing geotextile strength class adjacent to walls
16.15 Pavement reduction with geotextiles
16.16 Bearing capacity factors using geotextiles
16.17 Geotextiles for separation and reinforcement
16.18 Reinforcement location
16.19 Geotextiles as a soil filter
16.20 Geotextile strength for silt fences
16.21 Typical geotextile strengths
16.22 Geotextile overlap
16.23 Modulus improvements with Geosynthetic inclusions


17 Fill specifications
17.1 Specification development
17.2 Pavement material aggregate quality requirements
17.3 Backfill requirements
17.4 Typical grading of granular drainage material
17.5 Pipe bedding materials
17.6 Compacted earth linings
17.7 Constructing layers on a slope
17.8 Durability of pavements
17.9 Dams specifications
17.10 Frequency of testing
17.11 Rock revetments
17.12 Durability
17.13 Durability of breakwater
17.14 Compaction requirements
17.15 Earthworks control
17.16 Typical compaction requirements
17.17 Typical compacted modulus values
17.18 Compaction layer thickness
17.19 Achievable compaction
17.20 Acceptable levels of ground vibration


18 Rock mass classification systems
18.1 The rock mass rating systems
18.2 Rock Mass Rating System – RMR
18.3 RMR system – strength and RQD
18.4 RMR system – discontinuities
18.5 RMR – groundwater
18.6 RMR – adjustment for discontinuity orientations
18.7 RMR – strength parameters
18.8 RMR – application to tunnels, cuts and foundations
18.9 RMR – excavation and support of tunnels
18.10 Norwegian Q system
18.11 Relative block size
18.12 RQD from volumetric joint count
18.13 Relative frictional strength
18.14 Active stress – relative effects of water, faulting, strength/stress ratio
18.15 Stress reduction factor
18.16 Selecting safety level using the Q system
18.17 Support requirements using the Q system
18.18 Prediction of support requirements using Q values
18.19 Prediction of bolt and concrete support using Q values
18.20 Prediction of velocity using Q values
18.21 Prediction of Lugeon using Q values
18.22 Prediction of advancement of tunnel using Q values
18.23 Relative cost for tunnelling using Q values
18.24 Prediction of cohesive and frictional strength using Q values
18.25 Prediction of strength and material parameters using Q values
18.26 Prediction of deformation and closure using Q values
18.27 Prediction of support pressure and unsupported span using Q values
18.28 Geological strength index – structure description
18.29 Geological strength index – discontinuity description
18.30 Geological strength index – estimating value
18.31 Relationship of rock constant m
18.32 Geological strength index – values of parameter m for a range of rock types
18.33 Mohr-Coulomb strength parameters derived from GSI


19 Earth pressures
19.1 Earth pressures
19.2 Limit state modes
19.3 Earth pressure distributions
19.4 Coefficients of earth pressure at rest
19.5 Variation of at rest earth pressure with OCR
19.6 Variation of at rest earth pressure with OCR using the elastic at rest coefficient
19.7 Movements associated with earth pressures
19.8 Active and passive earth pressures
19.9 Distribution of earth pressure
19.10 Application of at rest and active conditions
19.11 Application of passive pressure
19.12 Use of wall friction
19.13 Values of active earth pressures
19.14 Values of passive earth pressures
19.15 Compaction induced pressures
19.16 Live loads from excavators and lifting equipment


20 Retaining walls
20.1 Wall types
20.2 Gravity walls
20.3 Effect of slope behind walls
20.4 Embedded retaining walls
20.5 Typical pier spacing for embedded retaining walls
20.6 Wall drainage
20.7 Minimum wall embedment depths for reinforced soil structures
20.8 Reinforced soil wall design parameters
20.9 Location of potential failure surfaces for reinforced soil walls
20.10 Sacrificial thickness for metallic reinforcement
20.11 Reinforced slopes factors of safety
20.12 Soil slope facings
20.13 Wall types for cuttings in rock
20.14 Drilled and grouted soil nail designs
20.15 Driven soil nail designs
20.16 Sacrificial thickness for metallic reinforcement
20.17 Design of facing
20.18 Shotcrete thickness for wall facings
20.19 Details of anchored walls and facings
20.20 Anchored wall loads
20.21 Anchor ultimate values for load transfer in soils
20.22 Rock anchor bond stress
20.23 Anchor bond length


21 Soil foundations
21.1 Foundation descriptions
21.2 Techniques for foundation treatment
21.3 Types of foundations
21.4 Strength parameters from soil description
21.5 Bearing capacity
21.6 Bearing capacity factors
21.7 Bearing capacity of cohesive soils
21.8 Bearing capacity of granular soils
21.9 Settlements in granular soils
21.10 Upper limits of settlement in sands
21.11 Factors of safety for shallow foundations
21.12 Factors of safety for driven pile foundations
21.13 Pile characteristics
21.14 Working loads for tubular steel piles
21.15 Working loads for steel H piles
21.16 Load carrying capacity for piles
21.17 Pile shaft capacity
21.18 Pile frictional values from sand
21.19 Earth pressure coefficient after pile installation
21.20 End bearing of piles
21.21 Pile shaft resistance in coarse material based on N-value
21.22 Pile base resistance in coarse material based on N–value
21.23 Design parameters for pipe piles in cohesionless siliceous soils
21.24 Pile interactions
21.25 Influence zone for end bearing piles in sands
21.26 Point of fixity
21.27 Uplift on piles
21.28 Plugging of steel piles
21.29 Time effects on pile capacity
21.30 Piled raft foundations for buildings
21.31 Piled embankments for highways and high speed trains
21.32 Dynamic magnification of loads on piled rafts for highways and high speed trains
21.33 Allowable lateral pile loads
21.34 Load deflection relationship for concrete piles in sands
21.35 Load deflection relationship for concrete piles in clays
21.36 Bending moments for PSC piles in stiff clays


22 Rock foundations
22.1 Rock bearing capacity based on RQD
22.2 Rock parameters from SPT data
22.3 Bearing capacity modes of failure
22.4 Compression capacity of rock for uniaxial failure mode
22.5 Ultimate compression capacity of rock for shallow foundations
22.6 Compression capacity of rock for a shear zone failure mode
22.7 Rock bearing capacity factors
22.8 Compression capacity of rock for splitting failure
22.9 Rock bearing capacity factor for discontinuity spacing
22.10 Compression capacity of rock for flexure and punching failure modes
22.11 Factors of safety for design of deep foundations
22.12 Control factors
22.13 Ultimate compression capacity of rock for driven piles
22.14 Shaft capacity for bored piles
22.15 Shaft resistance roughness
22.16 Shaft resistance based on roughness class
22.17 Design shaft resistance in rock
22.18 End bearing capacity of rock socketed piles
22.19 Load settlement of piles
22.20 Pile refusal
22.21 Limiting penetration rates
22.22 Pile installation


23 Movements
23.1 Types of movements
23.2 Foundation movements
23.3 Immediate to total settlements
23.4 Consolidation settlements
23.5 Typical self-weight settlements
23.6 Limiting movements for structures
23.7 Limiting angular distortion
23.8 Relationship of damage to angular distortion and horizontal strain
23.9 Movements at soil nail walls
23.10 Tolerable strains for reinforced slopes and embankments
23.11 Movements in inclinometers
23.12 Acceptable movement in highway bridges
23.13 Acceptable angular distortion for highway bridges
23.14 Serviceability and ultimate piles design
23.15 Tolerable displacement for slopes and walls
23.16 Observed settlements behind excavations
23.17 Settlements adjacent to open cuts for various support systems
23.18 Tolerable displacement in seismic slope stability analysis
23.19 Seismic performance criteria
23.20 Rock displacement
23.21 Allowable rut depths
23.22 Levels of rutting for various road functions
23.23 Free surface movements for light buildings
23.24 Free surface movements for road pavements
23.25 Allowable strains for roadways
23.26 Limiting strains for mine haul roads
23.27 Tolerable deflection for roads
23.28 Tolerable deflection for roads based on CBR
23.29 Tolerable deflection for proof rolling
23.30 Peak particle velocity
23.31 Vibration from typical construction operations
23.32 Perception levels of vibration


24 Appendix – loading
24.1 Characteristic values of bulk solids
24.2 Surcharge pressures
24.3 Live load on sloping backfill
24.4 Construction loads
24.5 Ground bearing pressure of construction equipment
24.6 Vertical stress changes


25 Appendix – conversions
25.1 Length, area and volume
25.2 Mass, density, force and pressure
25.3 Permeability and consolidation


26 References
26.1 General – most used
26.2 Geotechnical investigations and assessment
26.3 Geotechnical analysis and design


Index