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)
(Adobe)
(Reinforced Concrete)
2010 Chile Earthquake (M8.8)
(Reinforced Concrete)
2011 Japan Earthquake (M9.0)
2011 Japan Earthquake (M9.0)
(Reinforced Concrete)
Earthquake (ground shaking) damages are not severe in Sendai.
Nuclear Disaster
It was tsunami caused the backup generator failure – lost cooling
Design PGA on base-rock: 0.6g ( for all)
Design PGA at No.5 base-mat: 0.45g
Observed PGA at the base-mat:
No. 3: 0.51g
No. 4: 0.32g
No. 6: 0.43g
(Irikura, 2011)
(Masaki and Koike, 2011)
• 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
Seismic Codes and Source Documents - Past
NEHRP
SEAOC
Provisions
Blue Book
ASCE 7
(Seismic)
Standard
Building Code
BOCA National
Building Code
Uniform
Building Code
International Building Code
(Kircher, 2010)
Seismic Codes and Source Documents – Current
NEHRP
Provisions
ASCE 7
(Seismic)
International
Building Code
NFPA 5000
Building Code
(Kircher, 2010)
California
Building Code
Development of NEHRP Design Ground Motion
Seismic Hazard Map
(USGS)
Science
BSSC – Seismic Design Procedures
Reassessment Group (SDPRG)
Policy
Seismic Design Ground Motions
(FEMA)
Federal agencies
State Agencies
Other organizations
Seismic Design Procedures Reassessment Group
Project 07 – Joint effort of the BSSC, FEMA and USGS
Scope/Objectives
• Revisit products of Project
97 in light of new seismic
hazard information
(developed by the USGS)
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)
• Develop revised seismic
Dr. James R. Harris, SE (ASCE 7 past Chair)
design maps and
procedures reflecting these Dr. John “Jack” R. Hayes, PE, NIST (NEHRP)
Mr. William T. Holmes, SE (PUC past Chair)
new data for inclusion in
Mr. John D. Hooper, SE (ASCE 7 SSC Chair)
the 2009 NEHRP
Procedures (and ASCE/SEI Dr. Jeffrey K. Kimball, DOE NNSA
7-10 and model building
Dr. Nicolas Luco, USGS
codes)
Prof. Andrew Whittaker, SE, SUNY Buffalo
Mr. Michael Mahoney, FEMA
(Kircher, 2010)
NEHRP Design Map 0.2 sec Spectral Response
Acceleration for the U.S. (2% PE in 50 yrs., NEHRP)
2g
4g
(2009 NEHRP Provisions)
California
Central U.S.
Two times gravity
San Francisco
Paducah
Memphis
Four times gravity
NEHRP
0.2 sec Spectral Response Acceleration
NEHRP Design Map 1.0 sec Spectral Response
Acceleration for the U.S. (2% PE in 50 yrs., NEHRP)
1g
2g
(2009 NEHRP Provisions)
California
Central U.S.
One times gravity
Paducah
San Francisco
Memphis
Two times gravity
1.0 sec Spectral Response Acceleration
Problems in western Kentucky
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.
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/
USGS Twenty-Year Did You feel It
U.S. G.S. (Leith and others, 2009)
GPS results
California
Deformation rate: > 30 mm/y
Central U.S.
Deformation rate: < 3 mm/y
Active Plate Tectonics
Intra-Plate tectonics
Deformation rate: > 30 mm/y
Deformation rate: < 3 mm/y
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
(Peterson and others, 2008)
(Wang, 2009)
Red area: 0.40 – 0.80g
The National Seismic Hazard Maps
Inputs
Modeling (computer)
Scientific data
PSHA
Outputs
Hazard curves
HAZARD CURVES FOR SELECTED CITIES
1.0
0.0
0.10000
0.01000
2% in 50 Years
5% in 50 Years
CITIES
0.1
10% in 50 Years
0.2 sec Spectral Acceleration, %g
10.0
0.00100
Los Angeles
San Francisco
Seattle
Salt Lake City
New York City
Charleston
Memphis
0.00010
Annual Frequency of Exceedance
(Frankel et al., 1996)
0.00001
PSHA End Results: Seismic Hazard Curves
HAZARD CURVES FOR SELECTED CITIES
1.0
(Frankel et al., 1996)
Hazard
Hazard curves
curves
0.0
0.10000
0.01000
2% in 50 Years
0.1
5% in 50 Years
CITIES
10% in 50 Years
0.2 sec Spectral Acceleration, %g
10.0
0.00100
Los Angeles
San Francisco
Seattle
Salt Lake City
New York City
Charleston
Memphis
0.00010
Annual Frequency of Exceedance
0.00001
Hazard maps
Probabilistic Seismic Hazard Analysis – PSHA
Sensitivity Test
PSHA
Input
Output
A single EQ
“Computer
model”
Infinite GM
PGA hazard curve
Dis. =30km
TRP=?
Ann. frequency of exc.(1/year)
Site
(GM occurrence)
TRI =500 years
102
1.E-02
1.E-03
104
1.E-04
1.E-05
106
1.E-06
1.E-07
108
1.E-08
1.E-09
0.01
0.1
1
10
PGA (g)
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
Return period (years)
Source
(M7.7 occurrence)
Probabilistic Seismic Hazard Analysis – PSHA
VSAP
New Madrid Seismic Zone
TRI =500 -1,000 years
TRP=500 – 1,000 years
PSHA is a mathematical formulation derived from a
rigorous probability analysis on distributions of earthquake
magnitudes, locations, and ground motion attenuation
(McGuire, 2008).
t=1 year was omitted!!!
(v is the average event [earthquake] occurrence rate [per year])
PSHA calculates:
The annual probability of exceedance – probability of
exceedance in ONE year – a dimensionless quantity
Probabilistic Seismic Hazard Analysis – PSHA
(Cornell, 1968)
(Cornell, 1968)
Return period (years)
Yucca Mountain, NV
(Stepp and others, 2001)‫‏‬
10,000 years
1,000,000 years
11g
100,000,000 years
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)
Science
??????
BSSC – engineers,
seismologists, and others
Seismic Design Ground Motions
(FEMA)
Policy
??????
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
Horizontal-1
0
KTC-07-06/SPR246-02-6F (Wang and others, 2007)
Acceleration (cm/s/s)
-200
200
Horizontal-2
0
-200
200
Vertical
0
-200
0
10
20
30
40
Time (sec)
50
60
70
80
The KGS Scenario/Deterministic Ground Motion Hazard Maps
200
Horizontal-1
0
KTC-07-06/SPR246-02-6F (Wang and others, 2007)
Acceleration (cm/s/s)
-200
200
Horizontal-2
0
-200
200
Vertical
0
-200
0
10
20
30
40
Time (sec)
50
60
70
80
Problems in western Kentucky
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.
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!