Seismic Issues and Building Codes for Kentucky · PDF file2011 Japan Earthquake (M9.0) Earthquake (ground shaking) damages are not severe in Sendai. Nuclear Disaster . Observed PGA

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Seismic Issues and Building Codes

for Kentucky

Zhenming Wang, PhD, PE

Kentucky Geological Survey

University of Kentucky

http://www.uky.edu/KGS/geologichazards/

2011 KSPE Annual Convention

April 28, 2011

Outline

• Introduction

• Design Ground Motion Maps for Building Codes

• The USGS Seismic Hazard Maps

• The KGS Seismic Hazard Maps

• Summary

2010 Haiti Earthquake (M7.1)

(Modern building)

(Reinforced Concrete)

2010 Chile Earthquake (M8.8)

(Adobe)

(Reinforced Concrete)

2011 Japan Earthquake (M9.0)

(Reinforced Concrete)

2011 Japan Earthquake (M9.0)

Earthquake (ground shaking) damages are not severe in Sendai.

Nuclear Disaster

Observed PGA at the base-mat:

No. 3: 0.51g

No. 4: 0.32g

No. 6: 0.43g

Design PGA on base-rock: 0.6g ( for all)

Design PGA at No.5 base-mat: 0.45g

(Irikura, 2011)

(Masaki and Koike, 2011)

It was tsunami caused the backup generator failure – lost cooling

• The best way to prevent earthquake disaster

is to build better seismic resistant

infrastructure, buildings, and others

• The seismic provisions in building codes

are important

Standard

Building Code

Uniform

Building Code

BOCA National

Building Code

International Building Code

Seismic Codes and Source Documents - Past

SEAOC Blue Book

ASCE 7

(Seismic)

NEHRP Provisions

Standard

Building Code

Uniform

Building Code

BOCA National

Building Code

(Kircher, 2010)

Seismic Codes and Source Documents – Current

ASCE 7

(Seismic)

NEHRP Provisions

International

Building Code

California

Building Code

NFPA 5000

Building Code

(Kircher, 2010)

Development of NEHRP Design Ground Motion

Seismic Hazard Map

(USGS)

Seismic Design Ground Motions

(FEMA)

BSSC – Seismic Design Procedures

Reassessment Group (SDPRG)

State Agencies Other organizations Federal agencies

Policy

Science

Members

Dr. Charles A. Kircher, PE (SDPRG Chair)

Dr. C. B. Crouse, PE (PUC TS-3 Chair)

Prof. Bruce R. Ellingwood, PE, Georgia Tech

Mr. Ronald O. Hamburger, SE (PUC Chair)

Prof. Robert D. Hanson, FEMA (tech. advisor)

Dr. James R. Harris, SE (ASCE 7 past Chair)

Dr. John “Jack” R. Hayes, PE, NIST (NEHRP)

Mr. William T. Holmes, SE (PUC past Chair)

Mr. John D. Hooper, SE (ASCE 7 SSC Chair)

Dr. Jeffrey K. Kimball, DOE NNSA

Dr. Nicolas Luco, USGS

Prof. Andrew Whittaker, SE, SUNY Buffalo

Mr. Michael Mahoney, FEMA

Scope/Objectives

• Revisit products of Project

97 in light of new seismic

hazard information

(developed by the USGS)

• Develop revised seismic

design maps and

procedures reflecting these

new data for inclusion in

the 2009 NEHRP

Procedures (and ASCE/SEI

7-10 and model building

codes)

Seismic Design Procedures Reassessment Group

Project 07 – Joint effort of the BSSC, FEMA and USGS

(Kircher, 2010)

(2009 NEHRP Provisions)

NEHRP Design Map 0.2 sec Spectral Response Acceleration for the U.S. (2% PE in 50 yrs., NEHRP)

4 g

2 g

California Central U.S.

Memphis

San Francisco

NEHRP Four times gravity

Two times gravity

0.2 sec Spectral Response Acceleration

Paducah

(2009 NEHRP Provisions)

NEHRP Design Map 1.0 sec Spectral Response Acceleration for the U.S. (2% PE in 50 yrs., NEHRP)

1 g

2 g

Two times gravity

One times gravity

California Central U.S.

1.0 sec Spectral Response Acceleration

Paducah

San Francisco

Memphis

1) In 2001, Mr. David Master (a staff member from KY

congressman Ed Whitfield office): Why can I not build a

regular two-story house in Paducah?

2) SEAOK found that: impossible to construct residential

structures in westernmost Kentucky without enlisting a design

professional (IRC-2000).

3) DOE will not get permit from Ky-EPA to build a landfill at

PGDP for clear-up.

4) In 2002, One of the main reasons that Kentucky lost the

centrifuge facility ($2B) to Ohio.

Problems in western Kentucky

Closing Comments (Code Perspective)

• Code Ground Motions

– New “risk-targeted” ground motions of ASCE 7-10 (and the

2009 NEHRP Provisions) are now approved for use in model

building codes (e.g., 2012 IBC) almost, but not yet law

• Code Development Process (NEHRP)

– BSSC NIBS (FEMA) – Developed “collapse risk” concepts

for new ground motions

– ATC-63 (FEMA P-695) – Provided methods and established

the basis for generic building collapse risk safety goals

– USGS – Developed risk-targeted ground motions based on the

above and best available (current) science

(Kircher, 2010)

USGS 7-Day Seismicity in the U.S.

http://earthquake.usgs.gov/earthquakes/recenteqsus/

U.S. G.S. (Leith and others, 2009)

USGS Twenty-Year Did You feel It

GPS results California

Central U.S.

Deformation rate: > 30 mm/y Deformation rate: < 3 mm/y

Deformation rate: > 30 mm/y

Deformation rate: < 3 mm/y

Active Plate Tectonics Intra-Plate tectonics

Red area: 0.40 – 0.80g

National Seismic Hazard map for Central U.S. - PGA with 2% PE in 50 years

China - Wenchuan earthquake Actual (M7.9) PGA map

<0.10g (Wang, 2009)

(Peterson and others, 2008)

The National Seismic Hazard Maps

Outputs Inputs Modeling (computer)

Scientific data PSHA Hazard curves

10%

in

50

Ye

ars

5%

in

50

Ye

ars

2%

in

50

Ye

ars

HAZARD CURVES FOR SELECTED CITIES

0.10000 0.01000 0.00100 0.00010 0.00001

Annual Frequency of Exceedance

0.0

0.1

1.0

10.0

0.2

se

c S

pe

ctr

al

Ac

ce

lera

tio

n,

%g

CITIESLos Angeles

San Francisco

Seattle

Salt Lake City

New York City

Charleston

Memphis

(Frankel et al., 1996)

PSHA End Results: Seismic Hazard Curves

10%

in

50

Ye

ars

5%

in

50

Ye

ars

2%

in

50

Ye

ars

HAZARD CURVES FOR SELECTED CITIES

0.10000 0.01000 0.00100 0.00010 0.00001

Annual Frequency of Exceedance

0.0

0.1

1.0

10.0

0.2

se

c S

pe

ctr

al

Ac

ce

lera

tio

n,

%g

CITIESLos Angeles

San Francisco

Seattle

Salt Lake City

New York City

Charleston

Memphis

(Frankel et al., 1996)

Hazard curves

Hazard maps

Hazard curves

Infinite GM A single EQ

Output Input PSHA

“Computer

model”

Sensitivity Test

Probabilistic Seismic Hazard Analysis – PSHA

Site

(GM occurrence)

TRP=?

Source

(M7.7 occurrence)

TRI =500 years

Dis. =30km

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

1.E-02

0.01 0.1 1 10

An

n.

fre

qu

en

cy o

f e

xc

.(1

/ye

ar)

PGA (g)

PGA hazard curve

104

106

108

102

Re

turn

perio

d (years)

Annual Frequency of Exceedance (fy): The frequency (the number of events per year)

that a ground motion is equal to or greater than a specific value

Probabilistic Seismic Hazard Analysis – PSHA

VSAP

New Madrid Seismic Zone

TRI =500 -1,000 years

TRP=500 – 1,000 years

The annual probability of exceedance – probability of

exceedance in ONE year – a dimensionless quantity

(v is the average event [earthquake] occurrence rate [per year])

PSHA is a mathematical formulation derived from a

rigorous probability analysis on distributions of earthquake

magnitudes, locations, and ground motion attenuation

(McGuire, 2008).

PSHA calculates:

t=1 year was omitted!!!

Probabilistic Seismic Hazard Analysis – PSHA

(Cornell, 1968) (Cornell, 1968)

Yucca Mountain, NV

(Stepp and others, 2001)‏

Ret

urn

per

iod

(y

ears

)

1,000,000 years

10,000 years

100,000,000 years

11g

Hanks (2011) concluded that it (11g PGA) is overstated and had no answer “what is wrong”

Development of NEHRP Design Ground Motion

Seismic Hazard Map

(USGS)

Seismic Design Ground Motions

(FEMA)

BSSC – engineers,

seismologists, and others

Policy ??????

Science ??????

The KGS Scenario/Deterministic Ground Motion Hazard Maps

(Wang, 2010)

The KGS Scenario/Deterministic Ground Motion Hazard Maps

(Wang, 2010)

The KGS Scenario/Deterministic Ground Motion Hazard Maps

(Wang, 2010)

The KGS Scenario/Deterministic Ground Motion Hazard Maps

(Wang, 2010)

The KGS Scenario/Deterministic Ground Motion Hazard Maps

-200

0

200

-200

0

200

Acce

lera

tio

n (

cm

/s/s

)

0 10 20 30 40 50 60 70 80

-200

0

200

Time (sec)

Horizontal-1

Horizontal-2

Vertical

KTC-07-06/SPR246-02-6F (Wang and others, 2007)

The KGS Scenario/Deterministic Ground Motion Hazard Maps

-200

0

200

-200

0

200

Acce

lera

tio

n (

cm

/s/s

)

0 10 20 30 40 50 60 70 80

-200

0

200

Time (sec)

Horizontal-1

Horizontal-2

Vertical

KTC-07-06/SPR246-02-6F (Wang and others, 2007)

1) In 2001, Mr. David Master (a staff member from KY congressman Ed

Whitfield office): Why can I not build a regular two-story house in

Paducah?

2) SEAOK found that: impossible to construct residential structures in

westernmost Kentucky without enlisting a design professional (IRC-2000).

- Revised (similar to the KGS maps)

3) DOE will not get permit from Ky-EPA to build a landfill at PGDP for

clear-up.

- DOE has submitted a report on scenario/deterministic assessment

4) In 2002, One of the main reasons that Kentucky lost the centrifuge facility

($2B) to Ohio.

Problems in western Kentucky

Summary

• There is no question that Kentucky does have seismic hazards, but the hazards are not as high as those in California

• The best way to prevent earthquake disaster is to build better seismic resistant infrastructure, buildings, and others. Thus, the seismic provisions in the building codes are important.

Summary

• The issues and problems related to seismic provisions in the building codes are caused by the national seismic hazard maps

• The methodology used to produce the maps is not science

• The scenario/deterministic seismic hazard maps provide good alternatives for engineering design and other considerations

Thank You!

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