STATE OF NUMERICAL MODELLING IN PRACTICE:ONE PRACTITIONERS VIEW
Workshop on Nonlinear Modeling of Geotechnical Problems: From Theory to Practice
Presented by:Conrad W. Felice, Ph.D., P.E., P.Eng.PresidentLACHEL FELICE & Associates, Inc.Tel: 425-820-0800Email: [email protected]
Johns Hopkins UniversityNovember 3 & 4, 2005
Background
Maumee River Crossing• Single pylon cable stayed bridge• Tower height ≈ 380 ft• Foundations: Drilled shafts
– 256 – Diameter 7-8 ft.
• Construction ≈ $220 mil
At 15%, foundation costs are ≈ $33 million
Presentation Outline
• Where we are as a geotechnical profession
• Example project
• Opportunities to considerfor broader implementation
Presentation Outline
• Where we are as a geotechnical profession
• Example project
• Opportunities to considerfor broader implementation
Where we are as a geotechnical profession
• Perception of need
• Reluctant owners
• Availability/cost of tools & technology
• Bright spots
Where we are as a geotechnical profession
• Reluctant owners
• Availability/expense of tools & technology
• Bright spots
Issues• Competition• Liability• Cash flow• Trained staff• Unfamiliar with technology
Issues• Competition• Liability• Cash flow• Trained staff• Unfamiliar with technology
Where we are as a geotechnical profession
• Reluctant owners
• Availability/expense of tools & technology
• Bright spots
2000 2001 2002 2003 2004 2005Years
0
100
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400
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Num
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of P
LA
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Where we are as a geotechnical profession
• Reluctant owners
• Availability/expense of tools & technology
• Bright spots
Benicia
Where we are as a geotechnical profession
Sound transit
Tacoma narrows
Tren Urbano
Presentation Outline
• Where we are as a geotechnical profession
• Example project
• Opportunities to considerfor broader implementation
• Existing Casino 48,000 sq. ft.• Expansion includes:
– 23,360 sq. ft. of New Construction – 6-Story Cast-in-Place Concrete Hotel– 60,000 Gallon Water Tank– Related Grading/Landscaping/Parking
• Additional Future Expansion Possible• Complex Previous Grading and Settlement
Example project
• At least three episodes of previous grading • Fill Thickness varies from 0 to 10 feet
Example project
Example project
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7/6/20
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7/16/2
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7/26/2
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8/5/20
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8/15/2
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Tota
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imat
ed S
ettle
men
t (in
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SP#1 SP#2 SP#3 SP#4 SP#5SP#6 SP#7 SP#8 SP#9 SP#10REBAR#1 REBAR#2 REBAR#3 REBAR#4 REBAR#5REBAR#6 MP#1 MP#2 MIN Predicted MAX Predicted
Presentation Outline
• Where we are as a geotechnical profession
• Example project
• Opportunities to considerfor broader implementation
Opportunities to consider for broader implementation
Project delivery systems• Traditional – Design/Bid/Build • Performance/financial
– Design build– BOOT– DBOM– PPP
“Construction deserves more attention in design.” (Peck, 1973)
Opportunities to consider for broader implementation
The Direction of Our Profession
Opportunities to consider for broader implementation
• Implement “hands-on” construction• Greater emphasis on structural foundation
engineering• Introduce uncertainty and variability into widely
used simple models• Earlier introduction of simple models and
numerical analysis to reinforce theory and construction
• Material property estimation • Regional model needs• Practitioner training
Workshop on Nonlinear Modeling of Geotechnical Problems: From Theory to Practice