Combined Hurricane and Earthquake Hazard Component Vulnerability Analysis

1
Combined Hurricane and Earthquake Hazard
Component Vulnerability Analysis

• Terri R. Norton and Makola M. Abdullah, Ph.D.
• Florida AM University - Florida State University
• Wind Hazard and Earthquake Engineering Lab

2
OUTLINE

• Introduction
• Fragility Curves
• Research Objectives
• Research Proposal
• Vulnerability Analysis
• Damage Estimation

(USGS, 2004)
3
INTRODUCTION

• Each year the United States is affected by
  natural hazards.
• Hurricanes plague the east coast, while
  earthquakes affect the west.
• These hazards have the potential to cause
  extensive property damage and create mass
  casualties.
• Hurricane Andrew (1992), Hurricane Floyd (1999)
• Northridge Earthquake (1994)

4
INTRODUCTION cont.

• Understanding system vulnerability is essential
  to damage prediction.
• Vulnerability susceptibility of being damaged
• System vulnerability can be approximated through
  the collection of component vulnerabilities.
• Fragility curves are used to measure
  vulnerability.

5
FRAGILITY CURVES

• Relate the probability of being in or exceeding a
  building damage state to a response parameter.

f is the standard normal probability
integral mr is the median fragility Br is the
logarithmic standard deviation and x is the peak
(ground or spectral) acceleration
(FEMA, 1999)
6
FRAGILITY TYPES
Component vs. System Fragility

• System fragility is needed for input in most loss
  estimation software, like HAZUS.
• Research considers a building as an assembly of
  components.
• Unanwa (2000)
• Shinozuka (2000)

(Kishi, 2003)
7
OBJECTIVES

• Develop generalized component fragilities for
  wood-framed residential structures.
• Use fault tree analysis to identify component
  relationships
• Determine system vulnerability based on weighted
  component fragility.
• Estimate the economic loss of the structure.

8
PROPOSED APPROACH

• USGS peak acceleration map
• ASCE wind speed map
• Demand Conversion

• Component fragility based on converted demand
• Fault tree analysis
• Compilation of component fragility into system
  fragility

• Vulnerability converted into economic loss
• Total loss based on system vulnerability

9
INPUT DEMAND

• Earthquake loads
• USGS peak acceleration map ( g)
• Extreme wind loads
• ASCE 7 wind speed design map (mph)
• Loads converted to a generalized demand parameter

10
COMPONENT VULNERABILITY

• Each component fragility will be a function of a
  specific demand parameter.
• Windows may be a function of pressure
• Wall may be a function of shear force
• Existing research will assist in constructing
  component fragilities functions.
• Maximum likelihood method may also assist in the
  estimation of the two-parameter lognormal
  distribution function.

11
MAXIMUM LIKELIHOOD
where
and
F(x) probability of being damaged 1-F(x)
Probability of not being damaged x input
demand a 0 or 1, does not or does sustain damage
(Shinozuka, 2000)
12
FAULT TREE ANALYSIS

• Explains the logical sequence of damage
  propagation.
• From direct to indirect damage

13
SYSTEM VULNERABILITY

• A function of all the component fragilities
  combined.

14
SYSTEM VULNERABILITY

• A function of all the component fragilities
  combined.

(Shinozuka, 2000)
15
DAMAGE APPROXIMATION

Repair Cost
16
ECONOMIC LOSS

• Repair Cost
• Structural and Nonstructural damage
• Damage of contents
• Loss of Functionality

17
QUESTIONS?
(FEMA, 1994)
18
CONTACT INFO

• Terri R. Norton
• Email norton_at_eng.fsu.edu
• Makola M. Abdullah, Ph.D.
• Email abdullah_at_eng.fsu.edu
• http//www.eng.fsu.edu/departments/civil/index.htm
  l
• http//www.wheel.eng.fsu.edu

FAMU-FSU College of Engineering
19
FRAGILITY DEVELOPMENT

• ATC-13 (1985) heuristic damage functions
• estimates were based on the personal knowledge
  and experience of experts in the field
• HAZUS (1997) a combination of heuristic and
  analytical damage function models
• The focus of this assessment is the buildings
  response to ground motion
• Unanwa (2000) heuristic and analytical damage
  functions
• Consideration was given to damage propagation
  either through the direct impact of the wind or
  as a result of damage of other components

20
BUILDING COMPONENTS

• Roof covering
• Roof structure
• Beams and Columns
• Connections
• Slabs
• Partition walls
• Exterior wall
• Exterior doors windows

• Exterior doors
• Interior
• Mechanical Electrical
• Plumbing
• Foundation