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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Investigation
“You pay for site investigation whether you have one or not.”
Waltham, A.C. in “Foundations of Engineering Geology”, 1994
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
STEP BY STEP: Data Collection
• Office Data Collection
• Subsurface Exploration
• Field Survey / Mapping
• In Situ Testing
• Laboratory Testing
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
STEP BY STEP: Data Analysis
• Statistical Evaluation
• Geological Modeling
• Assessment of Probabilistic Confidence
• Kinematical Modeling
• Mechanical Modeling
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Pre-FeasibilityFeasibility
CorridorAssessment
Comparisonof Routes
First CostEstimate
Conceptual Design
Route Selection
Basic Assessment of
Rock Mass Behaviour,
Support Systems and Construction
Methods
Assessment of Routes
Cost Estimate
Detail DesignTender
Detail Construction
Design
Bill of Quantities
ContractualSet-Up
Final Cost Estimate
Final DesignConstruction
Final Determination
of Supportand
Construction Methods
Update of Construction Schedule and
Costs
PreliminaryDesign
Assessment of Rock Mass Behaviour,
Support Systems and Construction
Methods
Environmental Impact
Assessment
Cost Estimate
STEP BY STEP: Project phases and objectives of
project phases
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Cost - Benefit Relation of Investigation
Office Data CollectionField Survey / MappingSubsurface ExplorationIn-situ TestingLaboratory Testing
Feasibility StudyRoute SelectionPreliminary DesignDetail Design
Costs
Information
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Level of quality of investigation
• Any of the steps of investigation can be done at individual levels of quality
• Level of quality applied may depend on:
• Project requirements
• Project phase
• Available time
• Available resources
• Climate conditions
• Accessibility of project area
• Complexity of geology
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Methods of engineering geological investigation
Desk Studies, Remote sensing, aerial photo interpretation
Engineering geological field mapping
Core-drilling
Geophysical survey
In-situ and laboratory testing
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
DRILL CORE LOGGING Subsurface Investigations
• Exploratory drilling
• Geophysical surveys
• Borehole in situ testing
• Pilot tunnel
Laboratory testing
• Mechanical analyses
• Mineralogical analyses
Site Investigation
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
• Dumbleton, M. J. & G. West 1976. A guide to site investigation procedure for tunnels.Transport and Road Research Laboratory Report LR 740: 24 pp.
• Clayton, C.R.I., N.E. Simons & M.C. Matthews 1982. Site investigation - a handbook for engineers: 423 pp. Granada Publishing.
• Head, J. M. 1986. Planning and design of site investigations:1-5. In Hawkins, A. B.: Site investigation practice: assessing BS 5930: 423 pp. Geological Society of London.
• Anon 1987. Guide to site investigation, Geoguide 2: 365 pp. Geotechnical Control Office, Civil Engineering services Department. Hong Kong.
• BS 5930:1999. Code of practice for site investigation.
• A.F.T.E.S 2003. Guidline for characterization of rock mass useful for the design and theconstruction of underground structures. Association Française des Tunnels et de l'Espace Souterrain. Paris, France.
• Austrian Society for Geomechanics 2008. Guideline for the Geomechanical Design of Underground Structures with Conventional Excavation (2. edition)
Concepts and Guidelines
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Desk studies
Objectives of Desk Studies:
• Collecting of any available information on the project area
• Establishing a tentative geological model as a basis for further steps of investigation
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Assessment of Geological Models
• Conceptual Geological Models include three-dimensional interpretations of the distribution of - Geological structures - Rock types- Rock mass conditions
• The models are presented as - geological maps, - vertical and horizontal sections and, most
recently, - as 3D-models.
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Remote sensingLow level of quality: Interpretation of structures from image from Google-EarthExample: Patnitop tunnel (9 km long freeway tunnel) Kashmir, India
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Lineament analysis
Lineaments from 10m DEM
mapping scale: 1:50.000
max = 13.46%
0
90
180
270
lin_r10_clip.pln Datasets: 884
Interval: 10°
High level of quality:
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Aerial photo interpretation
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Examplegeomorphological mapfrom aerial photographSW –England)
Visual variables:
• Size
• Brightness
• Shape
• Pattern
• Orientation
• (Color)
Photo-geological investigations and mapping
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Geological maps
Carta Geoloica de Bolivia (GEOBOL & Swedish Geological AB)
Scale 1 : 100.000
Prepared from aerial photos, only a few field checks
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Geological mapsCarta Geoloica de Bolivia (GEOBOL & Swedish Geological AB) Scale 1 : 100.000 Prepared from aerial photos, only a few field checks
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Terrain Survey Intensity Level
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Nehemia Solomon
…. data InputETM+ - 2001ETM - 1986TM - 1972
Aerial Photo (37) –1994 (1:50000)
Topo Map (7) – 1997 (1:50000)
Tendaho Dam; Geological Modeling
Digital terrain analysis (DTA) procedure using aerial photographs and DEM´s
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Nehemia Solomon
DEM for 3D visualization …
Tendaho Dam; Geological Modeling
Digital terrain analysis (DTA) procedure using aerial photographs and DEM´s
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Engineering geological field mapping
• Field checks
• Mapping of rock exposures
• Field mapping
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Objectives of engineering geological field mapping
• Project-related assessment of underground condition
• Field-characterization of rocks with respect to their geotechnical properties
• Acquisition of statistically representative data (rocks, discontinuities…….)
• Identification of singularities (Karst, faults…)
• Basis for or updating of geological model
• Evaluation of uncertainty of the geological model
• Basis for further underground investigation (drilling, geophysical investigation
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Field checksLocation of field checks as fixed by usingGPS (Patnitop tunnel, Kashmir, India)
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Field checksFaults recognized by Google Earth image interpretation verified by field checking (Patnitop tunnel, Kashmir, India)
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Foliation
Cataclasticshear zone
Mapping of rock exposures: Data from outcrop of mylonitic gneiss in the Eastern Alps
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Xiaolangdi Multipurpose Dam Project –PR Chinamapping of rock exposuresscale 1:100
Mapping of rock exposures
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Engineering geological field mapping
Manuscript map, Carinthia, Austria scale 1:10.000
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Karte Andenbasistunnel oder Zentralraum Kärnten oder Ostbahn
Engineering geological field mapping
Final map, Carinthia, Austria scale 1:10.000
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Gefügeauswertung Zentralraum Kärnten
0
2
4
6
8
10
12
14
16
18
20
0.0 -0.05
0.10-0.15
0.20-0.25
0.30-0.35
0.40-0.45
0.50-0.55
0.60-0.65
0.70-0.75
0.80-0.85
0.90-0.95
1.00-1.05
1.10-1.15
1.20-1.25
1.30-1.35
1.40-1.45
1.50-1.55
1.60-1.65
1.70-1.75
1.80-1.85
1.90-1.95Spacing (m)
Frequency (%)
Horizontal discontinuity set Vertical discontinuity set
Discontinuity spacingData basis:Scan line mapping1.152 data points
joint set 1joint set 2
HPP Birecik
ZRK - HB2shistosity
ZRK - HB2slickensides
linears
Carinthia, Austria scale 1:10.000
Engineering geological field mapping
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Birecik Dam & HPP, TürkeiPaleostress analysis
Engineering geological field mapping
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Core Drilling
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Objectives of core-drilling
• Verification or falsification or upgrading of the geological model
• Characterization of rocks with respect to their geotechnical properties
• Characterization of discontinuities with respect to their geotechnical properties
• Localization of faults and changes in lithology
• Characterization and quantification of rocks mass properties
• Sampling of specimens for laboratory testing
• Evaluation of underground water conditions
• Execution of geophysical borehole tests or of geotechnical in-situ tests
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
• Investigation to great depth
• Continuous rock sampling and logging
• Direct access to the rock mass
• The rock mass can be investigated in different directions, a 3d insight into the rock mass is possible
• Groundwater does not interfere with investigation
• Calibration of geophysical sounding outputs
• Drill-hole can be used for in-situ testing and geophysical surveying
Advantages of core drilling
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Pin hole information only
Risks of misinterpretation
Cost – benefit relation frequently inadequate (especially in deep bore-holes)
Optimal interpretation requires experience and continuous supervision of drilling works
Layout of drilling pattern is decisive for the quality, amount and value of information obtained
Precautions in core drilling
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
• A layout design of drilling pattern according to geological requirements in order to establish a reliable conceptual geological model in accordance with other investigation
• Clearly formulated tasks of the borings with respect to weak and decisive points in information quality / quantity or to strengthen geologic assumptions
• The evaluation of all logable (and continuously logged) parameters of geotechnical concern (key parameters) so as to refine the geological model
• Inclusion, consideration and explanation of all findings, wetherthey assert previous assumption or contradict them
Optimization of core drilling investigation results requires:
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
• Suitable equipment
• Experienced foreman
• Optimal core recovery
• Flexible adoption of equipment due to changes in rock conditions
• Continuous monitoring of performance
Requests to the contractor
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
• Sufficient preparatory time
• Appropriate season for performance
• Contractual rights of the experts to have a suitable working place for the investigation of
• Flexible contract to modify the drilling program according to preliminary investigation
Requests to the client
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
• Diamond bits are the best and hardest, producing high quality core. Fastest cutting rates. Expensive
• Synthetic bits. Less expensive. Generally good quality cores.
• Tungsten carbide. Least expensive. Slower coring rates.
Drilling and Coring Bits
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Diamond, Carbide Tungsten, Sawtooth Carbide Type Bits
Types of Coring Bits
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
• Core Size: Larger better but more $
• Diamond setting: hardest vector set against the work
• Bit Profiles: Full-round, semi-round, flat crown, semi-flat
• Diamond size: relates to hardness and fineness of rock minerals
• Waterways: flushing cuttings & rock flour; Number of ports, slots, discharge direction.
• Matrix: secure diamonds & dissipate heat
Diamond Core Bits
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Single tube core barrel• Simple, rugged & cheap;
• Disadvantage: High mechanical stresses on core, washout due to full contact with high pressure flushing medium
Core barrels
• Double tube core barrel is the standard.
• Outer barrel rotates with cutting bit
• Inner barrel is either fixed or swivel type (with bearings) thatretains core sample.
• Core diameters generally range from 42 to 123 mm
• NX core: U.S. standard diameter = 54 mm (2.15 inches)
Double tube core barrel
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Single tube core barrel Double tube core barrels
Core BarrelsCore barrel mounting with swivel-type ball bearing assembly
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Core drilling: quality
Insufficient equipment
Unskilled personnel
Low quality of cores
Low core recovery
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Core drilling: quality
Worn out core barrel and drilling bits
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Diamond Drill Bits
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Core drilling: quality
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Core drilling: qualityHigh quality drilling rigUsing wireline core barrel drilling to depth of several 100 of meters
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Core drilling: quality
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Core drilling: quality
Core sampling according to quality of equipment ??
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Core drilling: quality
Core diameter 10 cm100% core recovery, even in faulted rock!
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
• Cores are valuable specimens
• Cores should be stored in either wooden boxes or corrugated cardboard boxes or sheet steel boxes.
• Box marked with boring number, depth of core run, type core, bit type, core recovery (core loss marked by replacement material, e. g. wooden log pieces), rock type, removed samples and other notes.
• Cores should be stored on a save place that guarantees easy access at any time
Storing of cores
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Storing of cores
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Storing of cores
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Storing of coresCore logging at the storage
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
• Dilatometer (pressuremeter) tests• Water pressure tests (Pumping t.)• Geophysical measurements:
- Caliper-log- Gamma (-Gamma)-log- Neutron - log- Resistivity-log- Acoustic bore hole televiewer (BHTV)- Formation micro scanning (FMS)
Drill-hole in-situ testing Standard In-hole Tests and
Measurements
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Dilatometer
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Bore-hole video camera
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Acustic bore-hole televiewer
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Acustic bore-hole televiewer
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Orientierung der Paläo - Hauptspannungen
See
höhe
(m
)T
eufe
(m)
Trennflächen-abwicklung
NW SE
Schematisches Profil
(Harnischflächen mitermitteltem Schersinn)
Geological drill core logging and kinematic discontinuity analysis
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Detachm
ent along foliation,developm
ent of clayey gouge
Kinematic Discontinuity Analyses on Drill Cores
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
fracture investigation result (traces highlighted), Koralm example, ISMES photo
Impression-Packer
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Geophysical (seismic cross-hole and others) investigation example including electric resistivity, density, magnetic susceptibility bore-hole logging
Geophysical bore-hole logging
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Example geophysical log in geotechnical soil sequence:
GRL Gamma Ray Log (Clay contents)
NL Neutron log, (Saturation, Permeability)
GGL Gamma-Gamma-Log (Density)
MAL Magnetic log (Silt, Fine Sand)
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Inclinometer
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert Inklinometer
Inclinometer
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Large scale in-situ testing: plateload test
HPP Feldsee, Austria
Pressuretunnel
2007
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Large scale in-situ testing: plate load test
HPP Feldsee, Austria, Pressure tunnel 2007: Test geometry and sensor setup
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INSTITUTE FOR ROCK MECHANICS AND TUNNELING
69
Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Large scale in-situ testing: plate loadtest
HPP Feldsee, Austria
Pressuretunnel
2007
INSTITUTE FOR ROCK MECHANICS AND TUNNELING
70
Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Large scale in-situ testing: plate load test
Hydraulic pressure vs time
Horizontal displacement vsnormal stress
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Geophysical survey
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Geophysical survey methods• Mechanical Wave Measurements
- Crosshole Tests (CHT)- Downhole Tests (DHT)- Spectral Analysis of Surface Waves- Seismic Refraction/Reflexion- Suspension Logging- Echo sounding (bathymetry)
• Electromagnetic Wave Techniques
- Ground Penetrating Radar (GPR)- Electromagnetic Conductivity (EM)/Resistivity (SR)- Magnetometer Surveys (MT)- Others- Gravymetry
- . . .
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Investigation Methods
Klima, Schubert
Objective of geophysical survey
• Filling gaps in information after geological field-mapping and core-drilling
• Updating and verifying geological model
• Optimum interpretation of geophysical data needs for a reliable geological model
• Drill-hole results necessary for calibration of geophysical data
• Therefore geophysical survey should be done after field-mapping and core-drilling
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Short Course Singapore 2011
Investigation Methods
Klima, Schubert
Seismical wave propagation investigationmethods
0 1000 2000 3000 4000 5000 6000 7000 8000
Compression Wave Velocity, Vp (m/s)
Fresh Water
Sea Water
Clay
Sand
Till
Ice
Weathered Rocks
Intact Rocks
Steel
P - Wave Velocities
0 1000 2000 3000 4000
Shear Wave Velocity, VS (m/s)
Fresh Water
Sea Water
Clay
Sand
Till
Ice
Weathered Rocks
Intact Rocks
Steel
S - Wave Velocities
} V s = 0
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Investigation Methods
Klima, Schubert
Crosshole seismic tomography: scheme and example analysis output
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Investigation Methods
Klima, Schubert
Crosshole seismic tomography: example analysis outputs
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Investigation Methods
Klima, Schubert
Vertical GeophonesSource(Plate)
Rock: Vp2
ASTM D 5777
Soil: Vp1
oscilloscope
x1x2x3x4
t1t2t3t4
Note: Vp1 < Vp2
zR
Determine depthto rock layer, zR
Seismic refraction
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Investigation Methods
Klima, Schubert
0.000
0.005
0.010
0.015
0.020
Trav
el T
ime
(sec
onds
)
0 10 20 30 40 50 Distance From Source (meters)
Horizontal Soil Layer over Rock
Vp1 = 1350 m/s
1
Vp2 = 4880 m/s
1z
x2
V VV Vc
c p2 p1
p2 p1=
−+
Depth to Rock:zc = 5.65 m
xc = 15.0 m
x valuest va
lues
Seismic refraction
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Klima, Schubert
Level of tunnel
Reflection Seismic
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Investigation Methods
Klima, Schubert
Electromagnetic Wave Geophysics
• Surface Mapping Techniques:
- Ground Penetrating Radar (GPR)- Electrical Resistivity (ER) Surveys- Electromagnetic Conductivity (EM)- Magnetometer Surveys (MS)
• Downhole Techniques
- Resistivity probes,
- 2-d and 3-d Tomography
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Investigation Methods
Klima, Schubert
Electrical Resistivity (ER)
• Resisitivity R (ohm-m) is an electrical property. It is the reciprocal of conductivity
• Arrays of electrodes used to measure changes in potential.
• Evaluate changes in soil types and variations in pore fluids
• Used to map faults, karst features (caves, sinkholes), stratigraphy, contaminant plumes.
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Investigation Methods
Klima, Schubert
Electrical Resisitivity Measurements
1 10 100 1000 10000
Bulk Resistivity, ρ (ohm-meters)
Clay
Loam
Loose Sands
Sands & Gravels
Glacial Till
Weathered Rocks
Resistivity Values (ConeTec & GeoProbe, 1997)
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Klima, Schubert
Example resistivity profiling output
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Investigation Methods
Klima, Schubert
Electric conductivity mapping, example
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Klima, Schubert
GIS based data management
Investigation data management
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Investigation Methods
Klima, Schubert
N S
Longitudinal section
3D - model
3D – modellongitudinal sectionswith fault systems
Eastern Expressway Project, Taiwan
Geological model
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