Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling...
Transcript of Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling...
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Use of Numerical Modelling to Mitigate Ground Risk
Gavin & Doherty Geosolutions Ltd.
CECA MEETING – SEPT 2017
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Overview
o Introduction to GDG
o Finite Element Modelling & Calibration
o Case Studies
o Flood Defences
o Retaining Walls
o High rise foundations
o Risk Analysis
o Conclusions
Todays Presentation….
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GDG Introduction
o Gavin & Doherty Geosolutions (GDG) is a specialist geotechnical & civil engineering consultancy
o Offices in London, Edinburgh, Dublin, and Belfast,
o GDG was formed in 2011 in a challenging market
o Grown throughout the last five years
o Team of 40 highly talented engineers
o Majority of our staff are PhD qualified
o We provide innovative geotechnical solutions & efficient civil engineering designs for challenging projects
About us ….
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Engineering Design Services
Structures Infrastructure
Offshore Renewables
R&D
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Engineering Design Services
o Concept Design
o Site Investigation Scoping
o Site Investigation Interpretation
o Civil Engineering Design
o Temporary Works Design
o Numerical Modelling (FEA)
o Performance monitoring / instrumentation analysis
o Expert Witness Services
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INFRASTRUCTURE
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INFRASTRUCTURE
o Geotechnical Interpretation & Ground Modelling for Road, Railway and Flood Defence Schemes
o Geological Assessments & Mapping
o Earthworks Design
o Material Suitability
o Hydrogeological review
o Civil Engineering Design
o Numerical Modelling
o Soil-Structure-Water Interaction Analysis
o Back-analysis of failures & Root Cause Analysis
SERVICES & EXPERTISE
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URBAN STRUCTURES
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URBAN STRUCTURES
SERVICES & EXPERTISE
o Basement & Foundation Engineering
o Soil-Structure Interaction
o Ground Movement Assessments
o Retaining Wall Analysis
o Excavation Support and Propping Design
o Construction Sequencing & Temporary Works
o Pile Design & Piled Raft Analysis
o Tunnel and basement impact assessments
o Ground Improvement Engineering
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OFFSHORE & MARINE
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OFFSHORE & MARINE
SERVICES & EXPERTISE
o Analysis and Design of Ports & Harbours
o Quay Wall Numerical Modelling
o Offshore Substructure Analysis
o Offshore wind foundation engineering
o Gravity structures, monopiles, jacket piles, etc…
o Pile Installation analysis & Interpretation of offshore driving data
o Site suitability assessments
o Jack-up vessel studies
o Back-analysis of failures & Root Cause Analysis
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• NNG Wind Farm
• Rampion Wind Farm
• Zawtika Gas Jacket Pile Analysis
• Hornsea Met Mast
• Firth of Forth Wind Farm Forensics
• Dogger Bank Jackup Analysis
• Shell Conductor Installation Studies North Sea
• Horizont Jacket Pile FEED
RELEVANT PROJECTS RENEWABLES
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RENEWABLES
SERVICES & EXPERTISE
o Site suitability and feasibility studies for onshore wind and onshore solar farms
o Geotechnical risk studies
o Peat stability assessments
o Earthworks engineering for roads, crane bases, hardstands, etc.
o Foundation design for gravity and piled bases
o Interaction analysis for soil-structure-turbine behaviour.
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Technical Presentation Sept 2017
www.gdgeo.com
• What is Ground Risk ?
Ground Risk
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Technical Presentation Sept 2017
www.gdgeo.com
• Analytical – Traditional Theoretical Hand (spreadsheet) Calculations
• Empirical – Traditional Approaches based on experience of empirical evidence
• Numerical – Finite Element (or Finite Difference)
• Observational Design Approaches
Pick the most appropriate tool for your project
(consider the limitations of the tool, the complexity of the project and the accuracy required)
Design Tools Available
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Technical Presentation Sept 2017
www.gdgeo.com
• Numerical Modelling Procedure to Determine Soil-Structure Response
• Modern Software Capable of Considering Complex Geometries
• The geometry is discretised into a mesh and the stresses and strains are resolved as loads/actions are applied
• Can accurately determine ground movements and structural stresses, provided the model is well calibrated
• Calibration requires (a) DATA and (b) EXPERTISE
Finite Element Method
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Technical Presentation Sept 2017
www.gdgeo.com
• Soil is highly non-linear
– Pick an appropriate constitutive model
Basics of Geotechnics
Stre
ss
Strain
Real Soil
Elastic-Plastic
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Technical Presentation Sept 2017
www.gdgeo.com
• FEM CALIBRATION
– Simulation of Lab Testing
– Look for repeatability
– Use range of test types
Finite Element Method
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Technical Presentation Sept 2017
www.gdgeo.com
• FEM CALIBRATION
– Simulation of Field Testing
Finite Element Method
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Technical Presentation Sept 2017
www.gdgeo.com
• TORONTO SEWER NETWORK TUNNEL ACCESS SHAFTS
• Access Shaft for TBM
• Complex Ground Conditions
• Underlying Aquifer
• Base Heave a Serious Concern !
• Design Solution Needed
CASE STUDY 1
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Technical Presentation Sept 2017
www.gdgeo.com
• Model Calibration
CASE STUDY 1
Non-Plastic Till Fine Sand to Silt Plastic Till Sand to Sand and Gravel
𝑫𝒓𝒂𝒊𝒏𝒂𝒈𝒆 𝑻𝒚𝒑𝒆 - Drained Drained Undrained Drained
𝑷𝒆𝒓𝒎𝒆𝒂𝒃𝒊𝒍𝒊𝒕𝒚 𝑚 𝑠 1 × 10−6 4 × 10−5 8 × 10−8 3 × 10−4
𝜸𝒖𝒏𝒔𝒂𝒕 𝑘𝑁 𝑚3 18 18 24 18
𝜸𝒔𝒂𝒕 𝑘𝑁 𝑚3 20 20 24.3 20
𝒆𝟎 - 0.5 0.5 0.301 0.5
𝑬𝟓𝟎𝒓𝒆𝒇
𝑀𝑃𝑎 30 30 20 30
𝑬𝒐𝒆𝒅𝒓𝒆𝒇
𝑀𝑃𝑎 30 30 20 30
𝑬𝒖𝒓𝒓𝒆𝒇
𝑀𝑃𝑎 90 90 80 90
𝑷𝒐𝒘𝒆𝒓 (𝒎) - 0.5 0.5 0.5 0.5
𝒄𝒓𝒆𝒇 𝑘𝑃𝑎 0 0 0 0
𝝋 ° 35 35 35.9 35
𝝍 ° 5 5 9 5
𝒑𝒓𝒆𝒇 𝑘𝑃𝑎 100 100 100 100
𝑹𝒇 - 0.9 0.9 0.9 0.9
𝒌𝟎,𝒙 - 1 0.8 1.2 0.8
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Technical Presentation Sept 2017
www.gdgeo.com
• TORONTO SEWER NETWORK TUNNEL ACCESS SHAFTS
• Undrained versus Drained
CASE STUDY 1
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Technical Presentation Sept 2017
www.gdgeo.com
• TORONTO SEWER NETWORK TUNNEL ACCESS SHAFTS
CASE STUDY 1
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Technical Presentation Sept 2017
www.gdgeo.com
• TORONTO SEWER NETWORK TUNNEL ACCESS SHAFTS
CASE STUDY 1
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Technical Presentation Sept 2017
www.gdgeo.com
• TORONTO SEWER NETWORK TUNNEL ACCESS SHAFTS
CASE STUDY 1
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Technical Presentation Sept 2017
www.gdgeo.com
• TORONTO SEWER NETWORK TUNNEL ACCESS SHAFTS
• Pore Pressures
(a) End of Excavation
(b) 10 weeks
(c) 20 weeks
(d) 50 weeks
CASE STUDY 1
(a) (b)
(c) (d)
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Technical Presentation Sept 2017
www.gdgeo.com
• TORONTO SEWER NETWORK TUNNEL ACCESS SHAFTS
• Failure Avoided
• Facilitated Economic Construction Sequence
• Observational Method Used to Minimise Risk
CASE STUDY 1
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Technical Presentation Sept 2017
www.gdgeo.com
• NATIONAL GALLERY UNDERPINNING ANALYSIS
CASE STUDY 2
Facilitate basement extension Geotechnical interpretation Geophysical profiling 3D Settlement Analysis of
Construction Stages Recommendation about
underpinning construction Final settlement design for
temporary and permanent works.
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Technical Presentation Sept 2017
www.gdgeo.com
• NATIONAL GALLERY UNDERPINNING ANALYSIS
CASE STUDY 2
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Technical Presentation Sept 2017
www.gdgeo.com
• NATIONAL GALLERY UNDERPINNING ANALYSIS
CASE STUDY 2
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Technical Presentation Sept 2017
www.gdgeo.com
• NATIONAL GALLERY UNDERPINNING ANALYSIS
CASE STUDY 2
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Technical Presentation Sept 2017
www.gdgeo.com
• NATIONAL GALLERY UNDERPINNING ANALYSIS
CASE STUDY 2
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Technical Presentation Sept 2017
www.gdgeo.com
• NATIONAL GALLERY UNDERPINNING
• Settlements predicted to be less than 10mm in worst case
• Generally less than 5 mm
• Concrete underpinning shown to be appropriate, however construction quality control critical
• Monitoring system tailored to target critical area of the building and critical point in the construction timeline
• Constant monitoring compared to design predictions with target levels set to stop construction if required.
CASE STUDY 2
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Technical Presentation Sept 2017
www.gdgeo.com
• Flood Defences
CASE STUDY 3
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Technical Presentation Sept 2017
www.gdgeo.com
• Flood Wall Analysis
CASE STUDY 3
• Stability Modelling
• Seepage Analysis Deemed Critical
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Technical Presentation Sept 2017
www.gdgeo.com
• Flood Defence Design
CASE STUDY 3
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Technical Presentation Sept 2017
www.gdgeo.com
• Flood Risk Analysis
CASE STUDY 3
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Technical Presentation Sept 2017
www.gdgeo.com
• Flood Risk Analysis
CASE STUDY 3
0.2
0.4
0.6 0.8 1
1
.2
1
.4
1.6 1.8 2 2.2 2.4 2.6
Design Flood Level
Gravel
Gravel
Silt
Peat
0.6
8202
m³/d
ays
2
.85
37 m
³/days
0
.12
612
m³/
days
Distance (m)
0 5 10 15 20 25 30 35
Ele
vatio
n (
m)
-13.5
-12.5
-11.5
-10.5
-9.5
-8.5
-7.5
-6.5
-5.5
-4.5
-3.5
-2.5
-1.5
-0.5
0.5
1.5
2.5
3.5
4.5
5.5
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Technical Presentation Sept 2017
www.gdgeo.com
• Flood Risk Analysis
CASE STUDY 3
0.2
0.4
0.6 0.8 1
1
.2
1
.4
1.6 1.8 2 2.2 2.4 2.6
Design Flood Level
Gravel
Gravel
Silt
Peat
0.6
8202
m³/d
ays
2
.85
37 m
³/days
0
.12
612
m³/
days
Distance (m)
0 5 10 15 20 25 30 35
Ele
vatio
n (
m)
-13.5
-12.5
-11.5
-10.5
-9.5
-8.5
-7.5
-6.5
-5.5
-4.5
-3.5
-2.5
-1.5
-0.5
0.5
1.5
2.5
3.5
4.5
5.5
0.4
0.6
0
.8
1
1.2
1
.4
1
.6
1.8 2 2.2 2.4 2.6 2.8
Gravel
Gravel
Silt
Peat
Distance (m)
0 5 10 15 20 25 30 35
Ele
va
tio
n (
m)
-13.5
-12.5
-11.5
-10.5
-9.5
-8.5
-7.5
-6.5
-5.5
-4.5
-3.5
-2.5
-1.5
-0.5
0.5
1.5
2.5
3.5
4.5
5.5
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Technical Presentation Sept 2017
www.gdgeo.com
• Flood Risk Analysis
CASE STUDY 3
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Technical Presentation Sept 2017
www.gdgeo.com
• Flood Wall Analysis
CASE STUDY 3
• Conceptual hyrogeological model developed
• Model Developed for Current Condition
• Model Calibrated Against Dynamic Borehole Records
Current Ground Level
Current Low River Level 0.75 mOD
Max Expected Tide appox. 1.60 mOD
Distance (m)
0 5 10 15 20 25 30 35 40 45 50 55
Ele
va
tion
(m
)
-9.55
-8.55
-7.55
-6.55
-5.55
-4.55
-3.55
-2.55
-1.55
-0.55
0.45
1.45
2.45
3.45
4.45
5.45
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Technical Presentation Sept 2017
www.gdgeo.com
• Flood Wall Analysis
CASE STUDY 3
• Calibration Process • Consider River Levels
• Tidal Variations
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Technical Presentation Sept 2017
www.gdgeo.com
• Flood Wall Analysis
CASE STUDY 3
• Model Storm Events • Consider River Levels
• Tidal Variations
• Design Options
-1
0
1
2
3
4
5
0 6 12 18 24 30 36
He
ad (
m)
Time (hours)
The change in Head (m) over time (hours)
-0.2 0
0.2
0.4
0.6 1
Low River Level -0.20 mOD
Gravel
Design Flood Level 3.80 mOD
Gravel
Silt
Swale
River Wall
Flood Defence Wall
Golf Course Road Hight Tide 1.54 mOD
0
.32
51
2 m
³/d
ays
0.2
852
9 m
³/days
Distance (m)
0 5 10 15 20 25 30 35 40 45 50 55
Ele
vation (
m)
-9.55
-8.55
-7.55
-6.55
-5.55
-4.55
-3.55
-2.55
-1.55
-0.55
0.45
1.45
2.45
3.45
4.45
5.45
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Technical Presentation Sept 2017
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• Piled-Raft for High Rise Development
CASE STUDY 4
• 32 Storey High Rise Development
• Several Concentrated Column Loads with very high forces
• High wind moment on tower
• Piled-Raft deemed most appropriate solution
• Stratigraphy consisted of London Clay
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Technical Presentation Sept 2017
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• Piled-Raft for High Rise Development
CASE STUDY 4
![Page 46: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/46.jpg)
Technical Presentation Sept 2017
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• Piled-Raft for High Rise Development
CASE STUDY 4
• Non-linear soil model used
• Moment applied as an eccentric force on a lever arm above the raft
• Pile Design optimised iteratively
![Page 47: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/47.jpg)
Technical Presentation Sept 2017
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• Piled-Raft for High Rise Development
CASE STUDY 4
• Designed to a settlement criteria rather than to a capacity value
• S<35mm
![Page 48: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/48.jpg)
Technical Presentation Sept 2017
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• Piled-Raft for High Rise Development
CASE STUDY 4
• Examine pile utilisation & optimise design
• Piles shortened by 7m
![Page 49: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/49.jpg)
Technical Presentation Sept 2017
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• Piled-Raft for High Rise Development
CASE STUDY 4
• Analyse the impact of the new raft on existing contiguous wall along site boundary
• Contig wall predicted to displace by approximately 9 mm
• Existing inclinometer casings used as a cheap/efficient monitoring solution
![Page 50: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/50.jpg)
Technical Presentation Sept 2017
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• MARINA PILE SETTLEMENT ANALYSIS • Redevelopment of Harbour, involving residential & office buildings on
piled pier
• Focus on estimating settlement of pipe piles
CASE STUDY 5
![Page 51: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/51.jpg)
Technical Presentation Sept 2017
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• MARINA PILE SETTLEMENT ANALYSIS
CASE STUDY 5
![Page 52: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/52.jpg)
Technical Presentation Sept 2017
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• MARINA PILE SETTLEMENT ANALYSIS
CASE STUDY 5
• Using state of the art settlement models to assess foundation performance (in-house design tools)
• Excellent prediction
• Confirmed pile acceptability
![Page 53: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/53.jpg)
Technical Presentation Sept 2017
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• Risk Modelling on a Large Scale (Rail Network)
CASE STUDY 6
2,800Km Track
4,900 Earthworks
5,100 Bridges
900 Level Crossings
![Page 54: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/54.jpg)
Technical Presentation Sept 2017
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Portarlington Derailment Aug 2008
Manulla Junction Landslide Aug 2007
Wicklow Derailment Nov 2009
Rushbrooke Rock Falls March 2014
• Recent Failures
CASE STUDY 6
![Page 55: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/55.jpg)
Technical Presentation Sept 2017
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Waterford Rockfall Dec 2013
Kilkenny Waterford Line Landslip Dec 2013
Tullamore Soil Slips and Rock Falls 2011/2012
Cabra Slope Failures 2012
CASE STUDY 6
![Page 56: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/56.jpg)
Technical Presentation Sept 2017
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PROBABILISTIC MODELLING
• High Level of Uncertainty Across the Asset Characteristics
• Consider COV of input parameters depending on data source
• Develop quantifiable risk profiles
• Hasofer Lind method used to calculate the probability of failure associated with each asset and its coupled limit state
• Outputs: reliability index (β), probability of failure
CASE STUDY 6
g(X) = R-SPf
probability
of failure
0
ßs[g(x)]
E[g(x)]
E[g(x)]
s [g(x)]ß[g(x)] =
Outputs: reliability index (β), probability of failure
![Page 57: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/57.jpg)
Technical Presentation Sept 2017
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• Risk Modelling on a Large Scale (Rail Network)
• Possible to quantify ground risk
• 4000 Assets
• No excuses for individual sites!
CASE STUDY 6
![Page 58: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/58.jpg)
Technical Presentation Sept 2017
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• Karst Risk Analysis
• Importance of Desk study research
CASE STUDY 7
![Page 59: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/59.jpg)
Technical Presentation Sept 2017
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CASE STUDY 7
Soil Profile from Intrusive Investigation
Layer
No.
Depth below
ground level (bgl)
Soil Type Description
1 0.6 to 0.9 m Made
Ground
Grey sandy GRAVEL with cobbles
2 0.9 m to 4 m*
Dynamic Probe No.
T2 encountered
soft soil to 11.1 m
bgl.
Glacial Till The till comprises reddish brown
sandy gravelly, low plasticity CLAY.
The fines content of the soil was
between 35 and 50%.
3 Below 4 m Waulsortian
Limestone
Light Grey, massive reef
LIMESTONE. The rock is strong to
very strong, with strong evidence
of karst solution features
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Technical Presentation Sept 2017
www.gdgeo.com
CASE STUDY 7
Soil Profile from Intrusive Investigation
Layer
No.
Depth below
ground level (bgl)
Soil Type Description
1 0.6 to 0.9 m Made
Ground
Grey sandy GRAVEL with cobbles
2 0.9 m to 4 m*
Dynamic Probe No.
T2 encountered
soft soil to 11.1 m
bgl.
Glacial Till The till comprises reddish brown
sandy gravelly, low plasticity CLAY.
The fines content of the soil was
between 35 and 50%.
3 Below 4 m Waulsortian
Limestone
Light Grey, massive reef
LIMESTONE. The rock is strong to
very strong, with strong evidence
of karst solution features
![Page 61: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/61.jpg)
Technical Presentation Sept 2017
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CASE STUDY 7
• Geophysics used to map risk
![Page 62: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/62.jpg)
Technical Presentation Sept 2017
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CASE STUDY 7
• Pragmatic Construction Regime Proposed
![Page 63: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/63.jpg)
Technical Presentation Sept 2017
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SUMMARY
o Advanced design tools have a place in the right projects
o FEM can allow more efficient design, save money and decrease risk
o Calibration is critical
o Recommend numerical modelling coupled with observational approach
o Monitoring provides the confidence to allow construction to proceed on time and in budget
![Page 64: Use of Numerical Modelling to Mitigate Ground Risk · 2017-09-08 · • Numerical Modelling Procedure to Determine Soil-Structure Response • Modern Software Capable of Considering](https://reader033.fdocuments.in/reader033/viewer/2022042023/5e7ae97ca5a4c8410e6fcb31/html5/thumbnails/64.jpg)
Technical Presentation Sept 2017
www.gdgeo.com
• QUESTIONS ???
Contact:
Paul Doherty
Conclusions