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

Hazard Examples Fire Earthquake krudesign (2007) © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

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

Life Safety Through the Eyes of an SE GET PEOPLE OUT THE DOOR ALIVE © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Life Safety Through the Eyes of an SE Structural Code generally does not consider: Building economics Business interruption losses Sustainability © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Building State After a Major Earthquake Northridge Earthquake Magnitude 6.7 Estimated Economic Loss $49.3 billion PEER (2000) © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Building State After a Major Earthquake: Northridge SDEDC (1994) © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Building State After a Major Earthquake: Northridge FEMA (2000) © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Life Safety Through the Eyes of an SE The purpose of this code is to establish the minimum requirements to safeguard the public health, safety and general welfare… (IBC 2006, 101.3) © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Life Safety Through the Eyes of an SE Misconception: A structure built to Code is earthquake proof. American (2004) © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Life Safety Through the Eyes of an SE KSL (2007) © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

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

Architectural Effect on Structure: Plan & Vertical Irregularities © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Architectural Effect on Structure: Plan Irregularity © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Architectural Effect on Structure: Vertical Irregularity © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Architectural Effect on Structure: Plan & Vertical Irregularities Code requires increased force for irregular framing Force increases 25-300% with a material increase of 12-300% © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Architectural Effect on Structure: 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 © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Architectural Effect on Structure: Redundancy Deficient Net result of non-redundant structure: non-redundant 1/3 increase in seismic force = net material increase (16-33%) (16-33%) © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Improved Seismic Design Options Performance Based Design Base Isolation Allows owner to pair Protects both structure ground shaking with post- and contents earthquake condition © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

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

Performance Based Seismic Design: 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 © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Performance Based Seismic Design: 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 © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Performance Based Seismic Design: 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 © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Performance Based Seismic Design: Cost Example Murphy (2005) © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Performance Based Seismic Design: Cost Example 0.45% of 1 year’s year’s Gross Revenue (1.6 days) © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Summary Recycled steel and fly ash should not be where our thinking or creativity stops. © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

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

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

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 accessed April 29, 2008. 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 accessed April 28, 2008. © Dunn Associates Inc, 2008 Earthquakes, Codes, & Sustainability

Earthquakes Sustainability, & Codes

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