Earthquakes Sustainability, & Codes

Earthquakes, Codes, &
Sustainability
by
Ronald H. Dunn, SE
Paul W. McMullin, SE, PhD
Salt Lake Sustainable Building Conference
April 29, 2008

Sustainable Design?

State of California (2005)

© Dunn Associates Inc, 2008
Earthquakes, Codes, & Sustainability

Outline

Life Safety to a Structural
Engineer

Effect of Architectural Design
Decisions on Structural
Material Consumption

Seismic Design Options
Performance Based Design
Base Isolation


Hazard Examples

Fire Earthquake

krudesign (2007)

College Academic Building:
3 Story, 26,000 SF
3-story- 26,000 sf.
% of
DIVISION Cost/SF Cost Total
O1 General Requirements 19.01 494,260 5.52%
O3 Concrete 13.55 352,300 3.94%
O4 Masonry 14.81 385,060 4.30%
O5 Metals 20.28 527,280 5.89%
O6 Wood & Plastics 13.54 352,040 3.93%
O7 Moisture Protection 35.91 933,660 10.43%
O8 Openings 48.63 1,264,380 14.12%
O9 Finishes 43.04 1,119,040 12.50%
1O Specialties 4.52 117,520 1.31%
11 Equipment 0.50 13,000 0.15%
12 Furnishings 7.31 190,060 2.12%
14 Conveying Systems 5.09 132,340 1.48%
15 Mechanical 74.00 1,924,000 21.49%
16 Electrical 36.18 940,680 10.51%
21 Fire Suppression /Protect 7.95 206,700 2.31%
Totals $344.32 $8,952,320 100.00%

Structural totals 48.64 $1,264,640 14.13%
Increase structural system cost by 23% $202,303
Increase total cost by only 2.2% $1,466,943 16.39%

Life Safety Through the Eyes of an SE

GET PEOPLE
OUT THE
DOOR ALIVE



Structural Code generally
does not consider:

Building economics

Business interruption losses

Sustainability


Building State After a Major Earthquake

Northridge Earthquake
Magnitude 6.7
Estimated Economic
Loss $49.3 billion

PEER (2000)

Building State After a Major Earthquake:
Northridge

SDEDC (1994)

Building State After a Major Earthquake:
Northridge

FEMA (2000)


The purpose of this code is to establish
the minimum requirements to
safeguard the public health, safety and
general welfare…
(IBC 2006, 101.3)



Misconception:
A structure built to Code is
earthquake proof.

American (2004)



KSL (2007)

The Question Matters

Never ask a Structural Engineer if
something is possible. He will get a
twinkle in his eye and say YES!

ASK HOW MUCH IT WILL COST
(Christensen 2004)


Architectural Effect on Structure:
Plan & Vertical Irregularities


Plan Irregularity


Vertical Irregularity


Plan & Vertical Irregularities

Code requires increased
force for irregular framing

Force increases 25-300%
with a material
increase of 12-300%


Redundancy Deficient

Code penalty for non-
redundant structures

Non redundant structures
have:
Less load sharing ability
Higher forces
Lower toughness

FEMA (2000)
ρ
Increase of 1.3 factor (ρ)
on seismic forces


Redundancy Deficient

Net result of non-redundant structure:
non-redundant

1/3 increase in seismic force =
net material increase (16-33%)
(16-33%)


Improved Seismic
Design Options

Performance Based Design Base Isolation
Allows owner to pair Protects both structure
ground shaking with post- and contents
earthquake condition


Performance Based Seismic Design:
Basics

Next generation seismic
design methodology

Originally developed by
FEMA for existing buildings

Applicable for new design

Considers each element’s
energy dissipation capacity


Pairing
Target Building
Performance Levels

Operational Performance

Performance Level (1-B)

Performance Level (5-E)
Life Safety Performance
Immediate Occupancy

Collapse Prevention
Level (3-C)
Level (1-A)
Once every 100 years a b c d

Once every 250 years e f g h
Hazard Level
Earthquake

Once every 500 years i j k l

Once every 2500 years m n o p


Levels & Acceleration

Performance levels Acceleration Options
Operational Typical
Immediate Occupancy 50%/50 (1/100 year)
Life Safety (IBC) 20%/50 (1/250 year)
Collapse Prevention 10%/50 (1/500 year)
2/3 of 2%/50 (IBC)
2%/50 (1/2500 year)

Any probability between
those listed above


Cost Example

Total1
Option Force Lateral % Lat Cost % Cost
Increase Cost Increase Increase
Typical Office 1.00 $1,378,000 0.00%
PBD IBC

Hospital 1.50 $1,643,325 19.25% 1.08%
10%/50- IO 2.15 $1,916,725 32.78% 2.18%
5%/50- IO 3.40 $2,216,700 43.76% 3.40%
1. Based on $125/SF
2. Gravity Frame $2,239,395

$38.25


Cost Example

Murphy (2005)

Cost Example

0.45% of 1 year’s
year’s
Gross Revenue
(1.6 days)


Base Isolation

Innovative design


Base Isolation


Summary

Recycled steel and fly ash
should not be where our
thinking or creativity stops.


References

American (2004). Earthquake-Proofing project still shaky in Utah, American
Library Association,
http://www.accessmylibrary.com/coms2/summary_0286-21752826_ITM,
last accessed April 28, 2008.
Center (2002). Strategic Insight, Center for Contemporary Conflict, Naval
Postgraduate School, Monterey, CA,
http://www.ccc.nps.navy.mil/contact.asp, last accessed April 28, 2008.
Christensen (2004). Gary Christensen, personal communication.
CNNMoney (2001). NY attack may cost $105B,
http://money.cnn.com/2001/10/04/news/wtc_cost/, last accessed April 28,
2008.
FEMA (2000). Recommended Seismic Design Criteria for New Steel Moment
Frame Buildings, FEMA-350, Federal Emergency Management Agency,
Washington D.C.
krudesign (2007). http://flickr.com/photos/krudesign/1006339582/, last
accessed April 29, 2008.


References

KSL (2007). Capitol Building Renovations are Earthquake Proof,
http://www.ksl.com/?nid=148&sid=1192949, last accessed April 28, 2008.
Murphy (2005). http://www.flickr.com/photos/jamiemurphey/56000489/, last
PEER (2000). Strong Motion Database, Pacific Earthquake Engienering
Research Center, http://peer.berkeley.edu/smcat/, last accessed April 28,
2008.
SCEDC (1994). Southern California Earthquake Data Center,
http://www.data.scec.org/chrono_index/northshow.html, lasted accessed
April 28, 2008.
State of California (2005). Guidelines for Earthquake Bracing of Residential
Water Heaters, State of California,
http://www.documents.dgs.ca.gov/dsa/pubs/waterheaterbracing_11_30_05
.pdf, lasted accessed April 28, 2008.
WTC (2008). World Trace Center Photos,
http://jeffreymunro.com/worldtradecenterphotos/slides/0126.html, last


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