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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!