Improving Damage Models for Critical...

Improving Damage Models for Critical Infrastructure

Jamie E. Padgett, Ph.D.

Associate Professor

Department of Civil and Environmental Engineering Rice University, Houston, TX

April 26, 2016

Sabarethinam Kameshwar Graduate Research Assistant

Carl Bernier Graduate Research Assistant

MOTIVATION Evolution of risk to infrastructure

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Evolving infrastructure risk

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Critical infrastructure systems

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BRIDGE INFRASTRUCTURE

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Failure modes

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Deck unseating

SH87 Rollover Pass Bridge Hurricane Ike

Scouring

Hurricane Ike Scenario Storm surge data courtesy of Dawson and Proft, UT Austin

Rollover Pass Bridge

Scour failure assessment framework

• Collect information on bridge and foundation – Bridge length – Size of columns

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– Foundation type – Soil type

Pile length

Column height

Column diameter

# of piles

Pile length

Scour failure assessment framework

• Gather flow data – ADCIRC simulations • Determine scour depth – SRICOS method for

time evolution of scour

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Scour depth

Scour failure assessment framework

• Place vehicles on bridge – Perform probabilistic analysis to assess failure

probability

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Is it safe?

Scour case study

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• Located in Freeport near Dow Chemical office

Scour case study

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• Located in Freeport near Dow Chemical office

Scour

TANK INFRASTRUCTURE

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Failure modes

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SH87 Rollover Pass Bridge Hurricane Ike

Buckling Floatation

Failure modes

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Buckling Floatation

PORTFOLIO OF TANKS IN THE HOUSTON SHIP CHANNEL

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Inventory of storage tanks

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• Inventory analysis through ArcGIS: o Tank dimensions and properties: aerial imagery o Tank height and bare earth elevation: LiDAR o Tank content: TCEQ database and HCAD parcel database

Evolution of inventory

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• Evolution from 1966 to 2014:

EVOLUTION OF RISK IN THE HOUSTON SHIP CHANNEL

Vulnerability assessment

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Vulnerability of tanks in the HSC

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• FEMA Base Flood Elevation for 0.2% chance of occurrence (≈21 ft)

Vulnerability of tanks in the HSC

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• Evolution of the number of tanks with high risk of failure (Pf ≥ 75%)

Potential hazardous spills due to storage tanks failure

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Location of major potential spills

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Summary

• New scour risk assessment framework for bridge infrastructures

• Scour fragility assessment of a case study bridge • Efficient fragility model for different AST failure

modes • Portfolio of ASTs from 1966 to 2014 • Time evolution of risk related to ASTs in HSC • Identification of critical areas in the HSC

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Future work • Extension of scour risk assessment framework for

portfolio of bridges to evaluate connectivity to critical energy infrastructures

• Integrated model of natural, physical, and social risks associated with oil infrastructure performance1.

• Quantification of the impact of risk mitigation strategies.

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1Co-PIs: P. Bedient, J. Elliot, R. Buono

THANK YOU