promoting the adoption and enforcement of seismic building ... · * code is titled the "boca...
TRANSCRIPT
SampleWorkshop Presentations
HANDOUTS:
a. U.S. Seismic Hazard -Map (same as Overhead 3)
b. Historic Earthquakes in 36 States
c. M Scale (explanation, descriptions of effects of various MMvffs)
d. Group Exercise #1- Community Earthquake Risk
e. Purpose and History -of Building Codes
f. Model Building Codes
g. Purpose of Seismic Code Provisions
h. Seismic Codes are Effective
i. Seismic Codes are Inexpensive
j. Group Exercise #2 - Responding to Arguments Against Seismic Codes
k. Arguments in Favor of Seismic Codes
1. Enforcing the Seismic Code: A Critical Link
m. Five Elements of Effective Code Enforcement
n. Group Exercise #3a - Action Plan for Adoption
o. Group Exercise #3b - Action Plan for Enforcement
p. Adopting Seismic Codes
q. Steps for Enforcement of Seismic Codes
Suggested handouts or overheads not included in this appendix:
1. Maps and images of historic local earthquakes, and, if maps are available, anticipated earthquakes. A goodsource of information is USCS Professional Paper 1527.
2. Consider handing out photocopies of Appendix D.
3. Develop a short questionnaire to solicit participant feedback.
137
T hree Aoin Areas Covered
1. Community risk for damage from earthquakeactivity
Purpose of building codes, and how they helpto protect the community from seismic risk
3. Importance of following through by enforcingthe building code, and how this too canbenefit the community
0o
Overhead 3
Known Historic (15 68-1989) Earthquakes in 47 StatesNumber of Quakes With Reported Maximum MMI of:
State VI VI] VilI+
Alabama 7 7-A laska .2..........13. .
Arizona 11 3.~~~~~~~~~~~~~~~~~~~~~~. 0.1t.. , ..... ... =....= . ..... U ,-Ark~ansa 83
California 329 131 66
Connecticut 2 IDelawr Florida 2 -
Hawaii 30 13 10
Illinois 18 12M -- S f-E In ,Z a0ind-iana 4
Kansas 4 2.., .0,,: = t t t f _ t; =~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ . .......
Louisiana IM aine 7 2 Massachusetts 8 7 3ic I -I - -
Minnesota 3Mississpp 2--
Missouri 14 2 3iMontana 35 4 dNebraska 4 2Nevada 28. .... S .
New Hampshire 7 2 1New jer 5 I 3New Mexico 29 7
New" ork 16'~~'' ^_~~^^"' 6 2... ...North Carolina , 2Nrth Da 3 IOhio 9 5
Okhoma ~ 9 2-Oregon 10 I,ennsvai 71-
Rhode Island I.--S r 3 = i,,l Z'= fi = T r-- -33- -3 South Ca__roliAna 17
South Dakota 6
Ua-h 31 8 -r -Vermont I
Washington 37 6 3West Viirg i ..ia .r - .- r ̂ .r r r Wyoming 8 1
Source: U.S. GeologicalSurvey, ProfessionalPaper 1527, 1993.
Note:This list includesonly earthquakes thataffected humansettlements.
0 0
Seismic Design Concepts
- IK I
I
Lateral forcesEarthquakes exert sideways forces onbuildings. Seismic design strengthensbuildings to withstand lateral forces.
Meul /
PUCTLrr
DuctilityThis property allows structures to bendbefore they break. Seismic design makesbuildings ductile to avoid catastrophiccollapse.
DriftStructures can withstand sidewaysmovement (drift), but their contents orneighboring buildings can be damaged.Seismic design limits drift.
0
Cl1-
4'-M --0 -wNP mwsd b.
--- I*; rift (Ab)
F;~~~ Iq
M~odified Mercalli Intensity ScaleThe Modified Mercalli Intensity Scale is a qualitative scale that describes the effectsof earthquake shaking. Because shaking decreases with distance from the center ofan earthquake, the intensity also decreases with distance. Larger earthquakes havehigher shaking intensity near the source, and shake a larger area.
124Q 1220 129-o 50 UV,00 BY75 70' 5 5°
48-v 4 Jrmml4A 4 -y-
460/ J. -any C\.=n-.s--= == = t*-----
.L_ -_ ..___ i .. ! ._.. _ = ogettn 2 _0 - - --\-
SPOR"~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~C
Northwest Washington earthquakeI Nov. 13, 1939. INMrth U.st hingonicrl thurveva Professional Paier 1527. 1993) Charlestone South Carolina earthquake Sept 1, 1886,,IA~~~mhve 11-41Z. Gt-oloarient Survey- Professional Puber 152 7. 1993) Charleston, South Carolina earthquake, Sept. 1, 1886 0~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .
1. . -.-. - - - .- Z� 'r, -- -K ---- - --, -- - - - , I
iModified Mercalli Intensity ScaleThe Modified Mercalli Intensity Scale is a qualitative scale that describes
the effects of earthquake shaking.
Size of Earthquake
(Magnitude)
E' x p ec;"''?'"j "!"uX'': t ed::!'"''!::'!!'!!':M M t!; ;!S;!<;S:i; : I;.';! !!!<! !! !!-:gS'!k
% Seismically Designed Buildings Damaged,
According to Standardized Damage States
B C D E;4 '4 '# :'S '# #": "g 'k'L' " "" "; '# # Le ' i;" A
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i' tiE'tia ' i,' ;'t 't' ,';; ':fiti.<;;;';E'ttE;'; tSEL;ikE;0i;k;' ' iL; ., ';;S i;';i' Sk'iSHv f 1''tESAS'S;AQ'Si";X;"'S4Ft'ti;t''t;i;.E'S;t'''f'W'tA''''ti.t';.;g;.;4ti;'tE;.i;,.' ,, ,*
cau-o.o /.J-o.UE:tittFitl;0;EEStdiS#ti;;ifX#4SSi44$fE;;EiStE;j404Ski;SEA;i4$XifEA None silnt M oderote Extensive (;omolete1 ,!S!1!W!!1'!;" f!ist!0,"0d.e !!W:;d,:!E' ','!!!t1'!4:'!;!!; 0!!!!;g;'!!! !!!.!;!';;!4;; t!!t;.'!s f - S
Distance
30 mi.
5 mi.
I mi.
to Fault
50 Mi.
40 mi.
30 mi.
3 mi.
010�1-M2�Source: EERI Ad Hoc Committee
A
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S j ,';' 5!!,!,fi 0,'!!2tti""j-;s}!ijj;, j, j!'j jjj. .'l jijtjj'\ jjjstl6aj.l
', ;!'iS !li j'.j! ati;'di gi" itiIi\§Jexii''ftti i;', l0Bti lilE iiti'i ! '; ikiS'l
!!!.!!!!i!!!!'i!!iSi!!!!.!!!!!;!!!idi!.5ifgggUS;!!!!:As;!!!;i!!!S!;!!ii!Nf!!ii!;!;ii 'I3 ,ti; teg fR t,.Ij,. i.B .E.,l ........ jj jj j.>ig ji,,.j.lj .... jjjjjtjjji,,, jjSj, ... jjjjN',';:;.,, ., !!;.i'S. ,, 'ij,:., .;,: '!.".:i';".3".."':. ':i":01l'S"""'t.":.!":E"is,
60-90%
35-60%
25-40%
5-25%
I 0-40%
35-45%
25-40%
5-25%
1-5%
I0-30%
20-40%
40-70%
<1%
<5%
3-10%
I 0-30%
0
<1%
<2%
<5%
MMI - VIEffectsFelt by all people, indoorsand out
People move aboutunsteadily
Some plaster cracks; finecracks appear in chimneys
Dishes, glassware, andwindows break
Books and pictures fall
Some furniture overturns
Objects fall from shelves
a
0.'-4
MMI - VIIEffectsMost people are frightened,general alarm
Many people find it difficultto stand
Water is disturbed andmuddied
Some sand and gravelstreambanks cave in
Chimneys crack to greatextent; walls crack somewhat
Plaster and stucco fall in largeamounts
Loosened bricks and tiles fall
Sidewalks cracka
C-00
MM - ViIlEffectsAlarm approaches panic
People driving vehiclesnotice the disturbance
Trees shake strongly, andbranches break off
Sand and mud are ejected fromthe ground in small amounts
Temporary and permanentchanges occur in springs andwells
Chimneys, columns,monuments fall
Major structural damage canoccur
a
'lO
I -
MMI- IXEffectsPeople generally panic
Ground cracks conspicuously
Masonry structures knockedout of plumb
Large parts of masonrybuildings collapse
Some buildings shift off offoundations and frames crack
Reservoirs are seriouslydamaged
Some underground pipesbreak
Substantial buildings (andelevated freeways such as this)can collapse
L - -71i. d =
S-,' %, ' to
tI ,.-~, '- +
0
(A-
Characteristics of Dangerous Buildings
* Brick or stone buildings
* Older buildings (especially large, multistoryolder buildings)
* Buildings with irregular shapes
* Buildings that appear to be top-heavy or withopen first floors (carports, all windows)
* {"Tilt-up" low-rise light industrial buildings (one-story warehouse-like buildings common inindustrial or office parks since the 1 960s)4
0 S S
Identifying Critical Structures
Critical structures are ones that would ser ouslyaffect the community if they collapsed or wereseverely damaged. Structures are deemed criticalif they :
* are needed immediately after an earthquake(fire and police stations)
* house needy populations (schools, hospitals,nursing homes)
* can have off-site effects (structures withflammable or toxic materials)
Purpose and History of Building Codes
Building Codes Protect Public Safety* Regulate building construction and use* Address structural integrity, fire resistance, safe exits, lighting,
and ventilation.@ Regulate construction materials* Classify structures by use
Building Codes Have a Long History in the U.S.* Have existed in North America since the seventeenth century* Comprehensive building regulations were introduced in the
mid- I 800si The three model building codes used today were initiated between
1927 and 1950* By 1960 more than 60% of American municipalities had adopted
building codes* By 1989 95% ofAmerican municipalities had adopted building codes
* 0 0
Model Building CodesBuilding Officials and Code Administrators International, Inc. (BOCA)* Headquarters in Country Club Hills, Illinois* Formed in 19 15* Code is titled the "BOCA National Building Code" (BNBC)* Code is revised every three years
International Conference of Building Officials (ICBO)* Headquarters in Whittier, California• Formed in 1922• Code is titled the "Uniform Building Code" (UBC)* Code is updated every three years
Southern Building Code Congress International, Inc (SB CCI)o Headquarters in Birmingham, Alabama* Founded in 1940* Publishes the "Standard Building Code" (SBC)* Code is updated every three years
Council of American Building Officials (CABO)* Founded in 1972 by BOCA, ICBO, and SBCCI* Publishes the One- and Two-Family Dwelling Code
Purpose of Seismic Code Provisions
Structures built according to a seismic code should:
* Resist minor earthquakes undamaged
a Resist moderate earthquakes without significantstructural damage even though incurringnonstructural damage
* Resist severe earthquakes without collapse,allowing safe evacuation of occupants
0o
Overheod 2 1
Seismic Building Code Timeline
1905 Model building law publishedby NBFU
1906 San Francisco earthquake kills3,000
1927 Uniform Building Code (UBC),with seismic provisions, firstpublished by ICBO
1933 Long Beach earthquake kills115
1935 Charles Richter devisesmagnitude scale forearthquakes
1940 Standard Building Code (SBS)published by SBCCI
1949 UBC contains first nationalseismic hazard map
1950 Basic Building Code (now theBOCA National Building Code)published by BOCA
1960 Sixty-percent of Americanmunicipalities had adopted oneof the model codes
Early'70s Study of earthquake-resistant
design provisions funlded byNSF
1971 San Fernando earthquakekills 65
1972 CABO formed
1973 UBC revised because of SanFernando quake
1976 UBC includes new seismicprovisions
1978 ATC releases AT'C3-06 report
1979 BSSC formed
1985 FEMA releases NEHIRPprovisions for new buildings
1989 Ninety-five percent ofAmerican municipalitiescovered by state-wide codes
1989 Loma Prieta, California,earthquake kills 63
1990 EO 12699 requires that allfederal agencies incorporateseismic resistant design innew buildings
1992 All t hree model codes requireseismic designs consistentwith NEHRP provisions
1992 Northridge, California,earthquake kills 57
1993 E012699 provisions tookeffect
1994 ICC formed
1994 EQ 12941 establishes seismicstandards for federally ownedor leased buildings
2000 ICC codes to be finished
Seismic Codes Are Effective
Ohbayashi Corporation's Study of Buildings Damaged inthe January 17, 199S, Earthquake in Kobe, Japan*
Green Tags Yellow Tags Red Tags(little or no damage) (some damage) (extensive damage)
Pre-1971 Buildings 42% 22% 36%(old seismic code)
1972-1980 72% 17% 11%(transitional period)
Post-1981 Buildings 84% 10% 6%(new seismic code)
*in this study, Ohbayashi Corporation reviewed buildings it had constructed tothe specifications of various seismic codes and assessed the extent of damageresulting from the 1995 earthquake.
Overhead 23
Seismic Codes Are Inexpensive
Increase in cost resultingfrom seismic design.
Source: Building Seismic Safety Council, 1985
0 0 0
Studies Indicate That the Benefits ofSeismic Codes Outweigh the Costs
Estimated costs and benefits of seismic 95D MP 55 5z, 755
building codes for Memphis, Tennessee,assuming damage from magnitude 6 and8 earthquakes in the southern New OttMadrid fault zone: benefits exceed costsby a factor of 1.8 for the magnitude 6 4-'v I -I% tevent and 10.3 for the magnitude 8 event. -------- -------
The expected damage over forty years ismore than three times greater than the ->
costs of building to code.
Benefits are underestimated because they Xi Jdo not account for the benefits of 3r - C7W o
reducing fatalities, injuries, fire potential, ..........or economic losses.
30' - \ XLNTO
v~~~~0U1 F F M \XI InRnS{
New Madrid earthquake, Dec. 16, 181 1. This was a U
magnitude 8 event. (Map: U.S. Geological Survey, -
Professional Paper 1527, 1993) 25- - - LET[
Arguments In Favor of selsmic Codes
* For elected officials: A damaging earthquake canoccur during your term of office.
* xFor elected officials: Citizens support seismic codes.
* Codes will not hurt business.
* A seismic code will improve successful survival ofthe next earthquake.
* Everyone else is doing it.
aIt's easy.
* It's good for the community.
* All communities need a seismic code regardlessof risk.
NJ
Poor Code Enforcement Results inDeficient Buildings
A substantialportion of the Idamage from XE a A I
Hurricane Andrewin 1992 was fromlack of enforcementof the South FloridaBuilding Code.(Source: FEMA 1993)
In a 1993 study,USC researchersfound that keyitems to resistseismic load arefrequently (13 to 72percent of surveyedunits) missing orflawed.
0
rb00.
- I -.,-3.1.7 � 4�*Nis"
Five Elements of Effective CodeEnforcement:
1. Code provisions must be up to date
2. Builders must apply for permits
3. A qualified reviewer must review building plans
4. Construction should proceed according toapproved plans
S. A qualified inspector must inspect theconstruction 0
h.i;.i
Adopting Seismic Code Provisions
Step I:
Step 2:
Step 3:
Step 4:
Determine the current building coderequirement (if any) and develop a strategyfor incorporating or initiating current seismicprovisions,
Gather support for the proposed changes.
Lobby the decision-making body withinformation explaining why the changes areneeded and describing the kind of supportyou have gathered.
Continue your involvement through theadministrative implementation andenforcement stages once the seismicprovisions are approved.
0
(D
(aALi
0a
Establishing an Effective Building CodeEnforcement Program
Step Ia
Step 2:
Step
Step
Step
Step
3 .4:
5:
6:
Adopt a model code.
Establish fee structures for permits and planreview.
Institute a systematic plan review system.
Adopt an inspection schedule.
Maintain a trained, qualified staff.
Be persistent but patient.
0(b
MT
Seismic Code Workshop
Some Selected Notable Earthquakes from 36 States
This table lists selected notable historical earthquakes from across the United States. Only states with at least oneevent of Modified Mercalli Intensity V[Il or greater are listed, and at least one such ev ent is described for each state.Only a few illustrative events are listed for highly seismic states, such as California and Alaska. Note that this list isbased on the location of the earthquake epicenter; many additional states have been affected by strong earthqu akesin neighboring states.
This information is summarized from U.S. Geological Survey Professional Paper 1527, Seismnicity of the UnitedStates, 1568-1989 (rev.), 1993. This publication is a particularly good source of information for historic seismicity in allthe states. It contains numerous maps of Modified Mercalli Intensities for historic earthquakes, including ones inyour state. This publication can be purchased from the USGS at (800) 435-7627, or it can be obtained from mostuniversity or state geological survey libraries.
Maximum
State Date MMI Magnitude Effects
AL Oct. 18, 1916
AK July 10,1958
March 28, 1964
AZ May 3, 1887
AR Dec. 16, 1811
Jan. 1, 1969
CA April 18, 1906
Mlarch 11, 1933
Feb. 9, 1971
M ay 2, 1983
Oct. 17, 1989
VTIT
XI
? lDestroyed numerous chimneys near Birmingham.
8.3 5 deaths, massive rockslide and ensuing wrare, extensive damage toport facilities at Yakutat.
9.2 125 deaths (110 from tsunamni), $311 million in property loss. Heavydamage from building collapses and landslides in Anchorage; tsunamidevastated many coastal areas.
X
X1.I
VI
7.4 Centered in Northern Sonora, caused 51 deaths in, Mexico, andwidespread damage in southeast Arizona from intensities of VIIS, VII[,and IX.
7.7 Part of New-v Madrid earthquake sequence, centered in northeastArkansas. Extensive ground deformation and landsliding throughoutsparsely-populated region. Chimneys toppled as far away as Cincin-nati. Sequence includes the largest earthquakes knoivn in 48 states.
4.3 Walls and floors cracked and dishes broken in Little Rock.
XI 7.7 Earthquake and fires killed 3,000 people and caused $524 million inproperty damage in and near San Francisco. Buildings and chimneyscollapsed, pipelines broke, soft ground severely deformed. Firesdestroyed a large part of San Francisco.
VEll 6.2 115 people killed, $40 million in property damage. Severe propertydamage in Long Beach and Compton, particularly to masonry struc-tures, especially those on soft ground.
XI 6.6 65 deaths, 2,000 injuries, and property damage of $505 million, mostlyin San Fernando Valley. Damage to hospitals, freeways, utilities, dams.Older buildings and thousands of chimneys damaged. Fault rupture,ground fracturing, and landsliding -caused extensive damage.
N/El 6.2 Coalinga earthquake caused $10 million in property damage andinjured 94 people. 8-block downtown area almost completely de-stroyed, primarily unreinforced brick buildi gs. Newver buildingssustained only superficial damage. Also destroyed hundreds of single-family homes and apartments.
DC 7.1 63 deaths, 3,757 injuries, and $6 billion in property damage. Damageto freeways and to older buildings on soft soils in San Francisco andOakland. Severe damage in and near Santa Cruz, primarily tounreinforced brick buildings. Engineered buildings, including thosenear the epicenter, performed well.
Handout B (/ of 4)
FEMA
.
Seismic Code Workshop
Some Selected Notable Earthquakes from 36 States Continued
CO Aug. 9,1967
Nov. 8, 1882
CT May 16, 1791
DE Oct. 9, 1871
HI Nov. 29, 1975
ID March 28,1975
Oct. 28, 1983
IL No'5 9, 1968
IN Sept. 27, 1909
KS Jan. 8, 1906
KY July 27, 1980
ME March 21, 1904
MVLA Nov. 18, 1755
MI July 27, 1905
MO Feb. 7,1812
Oct. 31, 1895
MT June 28,1925
Oct. 18, 1935
VII 5.3 Foundations, floors, and walls cracked, wiAndow s broke in northernsuburbs of Denver.
VAI 6.2 Minor damage in Colorado and southern Wyoming. Electricity cut offin Denver; plaster fell from the ceiling of a building at the University ofColorado in Boulder.
V1I ? Stone walls shaken dow n, tops of chimneys fallen in Middlesex County,northeast of New Haven. Felt in Boston and New r York.
V11
VHI
? Chimneys toppled and windows broken in -Wilmington area.
7.4 Two deaths, property damage of $4.1 million on island of Hawaii.Slight to moderate structural damage to 100 buildings from ground-shaking. Widespread ground deformation, subsidence, and faulting.Tsunami caused considerable damage to coastal areas.
VIIT 6.1 Shifted houses from, foundations and toppled chimneys in sparsely-populated Pocatello Valley Caused $1 million in damage.
IX 7.C Two deaths and $12.5 million in damage in Challis-MacKay area.Numerous commercial buildings damaged, primarily those built ofmasonryr 90 percent of chimneys in Mackay; were damaged. Extensivedamage to high school in Challis.
VII 5.3 Cracked foundations, dosvned chimneys, broken windom 's in southernIllinois. Most buildings with chimney damage w ere 30 to 50 years old.Felt in parts of 23 states.
Vii
VII
V1IVII
MAIR
E10
VII
VIEI
5.1 Downed chimneys and cracked plaster in Terre Haute, Covington, andPrinceton.
4.9 Fallen chimneys and cracked plaster in and near Manhattan.
5.0 Caused $1 million damage in Maysville to 37 commercial and 269residential structures. Old multistory brick structures in the do wntownwere affected the most. Fallen chimneys and cracked ground occurred.Felt in parts of 15 states.
5.1 Overthrew chimneys in Washington County Felt throughout NewEngland.
? Up to 1,500 chimneys damaged in Boston, stone fences thrown down,ground cracking. Much of the damage in Boston wotas on filled land nearwharfs. Generated a tsunami that affected the Wttest Indies. Earthquakewas centered off Cape Ann.
4.5 Downed many chimneys and broke plate glass windows at Calumet,Houghton County.
7.9 Part of New Madrid earthquake sequence. Destroyed town of NewMadrid. Many houses damaged in St. Louis. Ground wvarping, fissur-ing, landslides. Sequence includes the largest earthquakes lanolin in48 states.
6.7 Extensive damage to schools churches, private houses, and almost allthe buildings in the commercial section of Charleston. Extensiv edamage also to public buildings and brick walls in Cairo, Illinois.Felt in parts of 23 states.
6.6 Severe damage to chimneys and schools in Gallatin County. Almostall masonry buildings showed damage.
6.2 This was the main shock in a series of at least three large earthquakesduring October. These caused an estimated total of $4 million in prop-erty damage in Helena. Two people were killed and 300 buildingsdamaged. Damage was most severe to old brick houses. Downedchimneys and cracked plaster common. Severe damage to HelenaHigh School (completed 2 months earlier) and other public buildings.
Handout 8 (2 of 4)
FEMA
Seismic Code Workshop FEAIA
Some Selected Notable Earthquakes from 36 States Continued
Aug. 18,1959
NE Nov. 15, 1877
NV Dec. 21,1932
NH Dec. 20-24,1940
NJ June 1, 1927
NM Jan. 23,1966
NY Aug. 10,1884
Sept. 5, 1944
NC Feb. 21,1916
OH March 9,1937
OK April 9,1952
OR March 25, 19993
July 16, 1936
SC Aug. 31,1886
Jan. 1, 1913
TIN Aug. 17,1865
TX Aug. 16,1931
x
vII
7.3 28 deaths, and $11 million in damage to highways and timber. Mostdisastrous effect was from a huge landslide in the Madison RiverCanyon.
5.1 Damaged courthouse and school at Columbus, cracked w alls. Felt inseven states.
X 7.2 Major earthquake in an uninhabited region, as is true of most ofNevada's major historical earthquakes. Chimaneys -and walls fell inMineral County. Large landslides occurred and boulders were shakenfrom cliffs.
VII 5.5 Two similarly-sized earthquakes damaged old houses and chimneys inCarroll County. Also cracked walls, broken pipes, and broken furniture.Minor damage in Maine, Massachusetts, New York, Vermont.
VII 7 Damage to chimneys and fallen plaster in Monmouth County.
VII 5.0 Damage to chimneys, brick walls, and plaster, especially at schools inDulce. Rock falls at Dulce Point.
VII 5.5 Severe property damage at Jamaica and Amityrille. Fallen chimneysand cracked walls throughout area.
VIIII 5.5 Caused $2 million in property damage at lM'assena, NY, and Cornwall,Ontario. At Massena, 90% of chimnreys were damaged, as were manyhouse foundations, plumbing, and masonry. Chimneys were downed inseveral NY towns.
V1I 5.2 Tops of chimneys and wvindows broken in Waynesville. Minor damagein wider area of NC and TN.
VIII 5.4 Damaged almost every chimney in Anna (Shelby 'Coun ty), severelycracked the schoolhouse, and damaged to ichurches. Felt in tallbuildings in Chicago, MilWwaukee, and Toronto.
VT- 5.5 Toppled chimneys and smokestacks, loosened bricks, and brokenwindows at El Reno, Oklahoma City, and Ponca City. Caused 15-meter-long crack in State Capitol building.
VII 5.6 Caused significant structural damage to many unreinforced brickbuildings at Scotts hMils and Mollala. Estimated $2 million in uninsuredlosses, and S12 million damage to public facilities. Cracked StateCapitol rotunda. (Source: EERI Newsletter, vol. 27, no. 5, 1993)
VII 5.8 Chimneys broken, houses shifted from foundations in Umatilla County.Several houses severely damaged, school damaged. Caused $100,000damage. Many ground cracks formed.
X 7.O. 60 deaths, $5-6 million in damage. Most structures in Charleston wereseriously damaged. Every brick and stone building was cracked. Largepublic buildings required extensive repair. 65% of brick buildings weredamaged, compared to 7% of wooden buildings. Structural damagealso in AL, OH, KY, VA, and WV Extensive cratering and fissuring,severely damaged railroad tracks. (Source: OWA LNuttli, G.A. Bollinger,R.B. Herrmann, The 1886 Charleston, South Carolina, Earthquake-A 1986Perspective, U.S. Geological Survey Circular 985, 1986)
VII 4.8 Overthrew chimneys, damaged plaster and stone wTalls in UnionCounty. Cracked walls of jail and courthouse in, Union.
VII 5.O Chimneys thrown down at Memphis, and chimneys damaged at NewMadrid, MO. Felt from St. Louis to Jackson, MS.
VIE 5.8 All buildings except wvood-frame houses were damaged in Valeentine,and all chimneys were toppled or damaged. Schoolhouse had to berebuilt. Landslides occurred in a wvidespread area.
Handout 8 (3 of 41
FEMSeismic Code Workshop
FEMASeismic 'Code Workshop
Some Selected Notable Earthquakes from 36 States Continued
March 12, 1934 VIlI
Aug. 30, 1962
VA Mhay 31, 1897
WA April 13,1949
April 29, 1965
WY June 30, 1975
VII
VITI
VI11
Guam August 8,1993 ?
6.5 hin a sparsely-settled area in Box Elder County but two people werekilled. Downed chimneys and cracked wTalls in brick buildings. Large
rockslides and fissures.
5.8 Severely damaged many unreinforced brick buildings in CacheValley. 75% of chimneys collapsed in Richmond, walls of many
houses were badly damaged, and several houses were unsafe for
occupancy. Property damage of $1 million. Landslides also occurred.
5.6 Damaged chimneys and brick houses in Giles County especially at
Pearisburg. Large area felt Intensity VII1, including Lynchburg, VTA,Bluefield, AWV, and Bristol, TN. Felt from Georgia to Pennsylvania.
6.7 8 people killed, $25 million in property damage in Puget Sound area.Almost all large buildings wvere damaged in Olympia, including eight
on the Capitol grounds. Several structures condemned, including
three schoolis, a church, and a library. At Seattle, houses on filledground were demolished, many old brick buildings were damaged
and chimneys toppled.
6.7 7 people killed, $12.5 million in property damage. In West Seattle,two schools wvere severely damaged and chimneys were damaged
extensively. Unreinforced brick buildings were damaged mostseverely, and wood-frame buildings performed very well.
6.4 Caused rockfallis, landslides, and cracks in a parking lot at
YellowAstone Park. Many park roads were closed. Ti o new geysersformed.
8.1 This very powerful earthquake was centered about 40 miles south of
Agana. Generated no tsunamis, no deaths, and comparatively little
damage to Guam's code-designed structures. The most significantdamage occurred to some of the tall hotels, possibly due to construc-tion quality problems. Significant ground failure problems occurred
in waterfront areas. (Source: EERI Newsletter, vol. 27, No. 10, October
1993)
Handout B (4 f 4)
S UT
Seismic Code Workshop
Effects of the most common damaging MMl intensity values
AM~lLevel Effects
V Felt by most people, indoors and out
Buildings tremble
Dishes and glassware break
Small or unstable objects overturn and may fall
Doors and shutters open or close abruptly
Small objects and furnishings move slightly
Liquids in open containers may spill slightly
VI Felt by all people, indoors and out
People move about unsteadily
Some plaster cracks; fine cracks appear inchimneys
Dishes, glassware, and windows break
Books and picture fall
Some furniture overturns
VII Most people are frightened
Many people find it difficult to stand
VWater is disturbed and muddied
Some sand and gravel streambanks cave in
Chimneys crack to great extent; vwalls cradksomewhat
Plaster and stucco fall in large amounts
Loosened bricks and tiles fall
Damage negligible in buildings of seismicdesign .and construction
Damage considerable in poorly built buildings
MMILevel Effects
VIII Ground becomes wAet to some extent, even onsteep slopes
Chimneys, columns, monuments fall
Damage slight in structures built to with-stand earthquakes
Damage considerable in ordinary substantialbuildings
IX People generally panicGround cracks conspicuously
Masonry structures knocked out of plumb
Large parts of masonry buildings collapse
Some buildings shift off of foundations
Reservoirs are seriously damaged
Some underground pipes break
Damage considerable in structures built towithstand earthquakes
Damage great in substantial buildings
X Ground cracks as large as several inches
Numerous landslides on riverbanks andsteep slopes
Most masonry and frame structures aredestroyed
Buried pipelines are torn apart or crushed
Wavy folds open in concrete pavements andasphalt surfaces
VIII People are alarmed
People driving vehicles notice the disturbance
Trees shake strongly, and branches break off
Sand and mud are ejected from the around insmall amounts
Temporary and permanent changes occur insprings and wells
Handout C
FEW
Seismic Code Workshop
* Group Exercise #1: Community Risk at MMI
SAFETY RATING SCALEDon't Know Unsafe Very Safe
? 1 2 3 4 5Safety Rating Built to Current
Building Code Specs?
Yiln?
Built to Current
Seismic Code Specs?
y/n'?
City Hall Building:
Fire Station(s):
School(s):
Hospital(s):
Recent large building(s):
Other major cormunity building(s):
W-here would you like most to be during an earthquake?
Where would you like least to be during an earthquake?
Handout D
FEMN
Seismic Code Workshop
* Purpose and History of Building Codes
Building codes regulate buildingconstruction and use in order toprotect the safety of occupants.Codes address structural integrityfire resistance, safe exits, lighting,and ventilation. Codes also regulateconstruction materials.
Building codes d.assify structuresby use and apply different standardsto each classification. For -example,office buildings and residentialmulti-unit buildings are in separatecategories with different perfor-mance (such as strength and stabil-ity) requirements.
The validity of building codes isbased on state police powers, whichallow regulation of activities andproperty to preserve or promote thepublic health, safety, and generalwelfare. Zoning ordinances andenvironmental protection regula-tions are also founded in policepowers.
Building Codes Have a LongHistory in the U.S.
Building codes to reduce the loss oflife, limb, and property have existedin North America since the seven-teenth century The -earliest buildingregulations addressed problemsresulting from dense urban con-struction, such as rapid spread offire. New York City, then called NewAmsterdam, first regulated chim-neys and roofing material in 1648.These regulations were aimed atcontrolling the destructive force offire in urban areas, as evidenced byLondon's 1666 fire, New York's 1835and 1845 fires, and the great Chicagofire of 1871.
Comprehensive building regula-tions were introduced in the mid-1800s. Building regulations were oftwo types: housing codes andbuilding codes. Housing codes wereintended to reduce the ill effects ofresidential overcrowding, and theirintroduction paralleled Europe'shousing and sanitation reform. NewYork City in the late 1850s adopted acitywide housing code in order toprovide air and light into dwellingsand reduce the risk of fatal hazards.Chicago followed by passing itsinitial tenement housing ordinancein 1874. Building codes were laterenacted to comprehensively specifyconstruction methods and materials.
In 1905 the National Board of FireUnderwriters published a modelbuilding law aimed at reducing firerisks. The three model buildingcodes used today were initiatedbetween 1927 and 1940. The use ofcodes spread with the growth ofnew building across the countryparticularly after World Wadr II. By1960 more than 60 percent of Ameri-can municipalities had adoptedbuilding codes.
Handout E
FEM1A
Seismic Code Workshop
Model Building Codes
A model building code is a documentcontaining standardized buildingrequirements applicable throughoutthe United States. Model buildingcodes are performance standardsspecifying the required performanceof all structures. They are publishedby private organizations, whosevoting members are governmentjurisdictions. The United States hasthree prominent model building codeorganizations: the InternationalConference of Building Officials(ICBO), Which publishes the UniformBuilding Code (LIC); the BuildingOfficials and Code AdministratorsInternational, Inc. (BOCA), whichpublishes the BOCA NVatlsoal BuildingCode (BN\TBC); and the SouthernBuilding Code Congress Interna-tional, Inc. (SBCCI7, which publishesthe Standard Building Code (SBC).Each organization also publishescompanion documents coveringmechanical work, plumbing, fireprotection, electrical w rork, energv,accessibility, and life safety codes.
In addition to writing and up dat-ing the codes, the organizations offera variety of support services, includ-ing such technical services as trainingseminars, code interpretation,technical and administrative publica-tions, customized consulting, videos,and softwiare. Each organizationoffers certification programs to allowskilled inspectors and plan review ersto be recognized for their levels ofknowledge and experience. Forexample, BOCA offers certificationby examination in tw-enty-twTocategories and ICBO in nineteencategories. SBCCI offers four levels ofcertification in various categories toencourage professional growththrough progressive levels of certifi-cation.
The model building codes arerevised periodically by a democraticprocess. Each organization allowLNs the
public to propose code amendmentsand hear testimony in meetingsorganized by the organization, somembers and nonmembers are equalparticipants. Active members of eachorganization vote on revisions afterfinal testimony is heard during theirannual meeting. The content of thecodes has become more similar overtime, although they still addressregional conditions and practices.The newest versions reflect a com-mon code format so that similartopics can be found in consistentlynumbered chapters among the codes.
Although the code organizationshave widespread membership, eachorganization's model building codeis predominantly adopted in oneportion of the United States. TheBINBC is predominantly adopted inthe northeast and north centralstates, the SBC predominates in thesouthern states east of the M/4issis-sippi, and the UJBC is predominant inthe western states, including Guam.
In addition, BOCA, ICBO, andSBCCI have moved forward on thedevelopment of a single model code,the International Building Code. OnDecember 9, 1994, the InternationalCode Council (ICC) was formed todevelop a single set of comprehen-sive and coordinated national codes.The advantages of a single code arenumerous. Code enforcementofficials, architects, engineers,designers, and contractors can haveconsistent requirements that can beused across the country and aroundthe world. Manufacturers can puttheir efforts into innovative products,instead of designing for all threeregional codes. To date, the ICC hasproduced codes that address plumb-ing and private sewage disposal. Thegoal is for the complete family ofinternational codes to be developedby the year 2000.
Building Officials and CodeAdministrators International,Inc. (BOCA). BOCA, headquar-tered in Country Club Hills,Illinois, was formed in 1915. Itsfirst code, the Basic Building Codenowv titled the BOCA ationalBuildbig Code (BNBC), waspublished in 1950 in an attempt tostandardize existing codes. TheBNBC is revised every threeyears, most recently in 1996, witha new edition due out in 1999.
International Conference ofBuilding Officials (ICBO). ICBOweas formed in 1922 to integratevarious design requirements intoone code. ICBO published its firstmodel code, the Uiniforn BuildingCode UBC), in 1927 from itsheadquarters in 'Whittier, Califor-nia. ICBO up dates the UBC everythree years. The latest edition waspublished in 1994.
Southern Building Code Con-gress International, Inc. (SBCCI).The third model building codeorganization, the SECCI wasfounded in 1940. Located inBirmingham, Alabama, it pub-lishes the Standard Buildhing Code(SBC). The SBC is updated everythree years, most recently in 1994.
Council of American BuildingOfficials (CABO). CABO wasfounded in 1972 by BOCA, ICBO,and SBCCI. The One- and Tim-Family Dwvellbing Code applies tothe construction, prefabrication,alteration, repair, use, occupancy7and maintenance of detached one-or tw,,o-family dwellings and one-family town houses not more thanthree stories in height
Handout F
FEW
Seismic Code Workshop,
Purpose of Seismic Code Provisions
Seismic Codes Are Designed toHelp Buildings Resist Earth-quakeShaking
It is important to understand thatseismic codes result in earthquake-resistant buildings rather thanearthquake-proof buildings. Theirpurpose is to protect life safety bypreventing building collapse andallowing for safe evacuation. Thecontents and interiors of buildings,even those of well-designed build-ings, may receive extensive damage,and entire functions of a buildingmay cease. And structural damagemay occur from major earthquakeground-shaking. According to theStructural Engineers Association ofCalifornia, structures built accordingto a seismic code should:
* resist minor earthquakesundamaged,
* resist moderate earthquakeswithout significant structuraldamage even though incurringnonstructural damage, and
* resist severe earthquakes withoutcollapse.
Occasionally even a code-designedbuilding may collapse due to uniquesite conditions or other factors. Areport completed by the EarthquakeEngineering Research Institute(EERI) just prior to the Northridge,California, earthquake summarizedexpected earthquake damage tobuildings designed according to the1991 UBC. It stated, for example,that shaking of Intensity NMII couldcause moderate damage (easilyrepairable) to 10 to 30 percent ofcode-designed buildings, andextensive damage Gongg-termnclosure, difficult to repair) to U to 5percent of code-designed buildings.This was the intensity lev, el experi-enced by much of the San Femando
Valley in January 1994, and build-ings performed generally as ex-pected.
Seismic Codes Reflect SocialJudgments RegardingAcceptableRisk and Cost
Seismic design standards reflectsociety's balancing of the risksversus the costs of designing towithstand that risk. They do this intwNTo ways: by designing for (a) anappropriate-sized e-vent and (b) anappropriate performance goal.Society cannot justify the expense ofdesigning for large but highlyimprobable events. So we select aground motion event-called thedesign event-that although largeand rare has a reasonable chance (10percent) of being exceeded during abuilding's lifetime (50 years). Theprobability selected reflects society'sattitude toward risk. This is similarto the philosophy long used forflood protection: Society is willing toabsorb the cost of designing for a100-year flood, but with the excep-tion of critical facilities it would notmake economic sense to design forthe 5OC-year or 1,000-year flood.
The goal of seismic codes is toensure that buildings will notcollapse, thereby killing thoseinside, if shaken by the design event.Seismic codes are for "life safety"and are not aimed at completelypreventing damage to existingbuildings. Additionally, it is impor-tant to realize that there is a 10percent chance of an earthquakeoccurring that exceeds the designevent.
Hando ut G
FEMA
Seismic Code Workshop FEMA
* Seismic Codes Are Effective
Seismic CodesAre Effective
Experience with recent earthquakesin the United States and throughoutthe world shows that seismic codeswork. Cities with seismic codessuffer much less damage than thosewithout such codes.
The Loma Prieta earthquakeclearly illustrates the effectiveness ofseismic codes. Occurring on October17,1989, this earthquake measured7.1 on the Richter scale and was thestrongest in the United States sincethe 1964 Alaskan earthquake. Itshook the San Francisco Bay Areaand killed sixty-three people.Although the ground-shaking wasintense vithin the metropolitanarea, few buildings collapsed. Mostof the damage occurred tounreinforced masonry buildingsbuilt before the adoption of seismiccodes. Nearly all major reinforcedconcrete structures built after WorldWar 11 survived without collapse.Even at the quake's epicenter newbuildings and buildings located onfirm ground suffered little damage.Informed observers attribute thesuccess to the required UBC seismiccodes. This example illustrates thatcode requirements reduced thedamage and loss of life during thismoderate earthquake.
A Kyoto University study of the1995 earthquake in Kobe, Japan,Richter magnitude 6.9, found thatdamage to reinforced concretebuildinrgs closely paralleled im-provements to seismic provisions inthe Japanese building code. Morethan 55 percent of pre-1970 build-ings (old version of code) wereseverely damaged, compared withno post-1980 buildings (newestversion of code). Results for steelbuildings were comparable.
Even smaller earthquakes cancause extensive damage where
buildings are not designed forseismic shaking. A Magnitude 5.6earthquake in 1993 at Scotts hMills,Oregon, caused significant structuraldamage to a number of unreinforcedmasonry (brick) buildings in thearea. A high school building wassignificantly damaged and vacated,16 residences and 54 businessessustained major damage, and theOregon State Capitol, in Salem,suffered cracking in the rotunda. Theestimated damage cost to publicfacilities alone was nearly $13million. This earthquake confirmedthe susceptibility of unreinforcedbuildings to severe damage, even ina minor earthquake.
Seismic Codes Are Inexpensive
Seismic codes add relatively little tothe costs of a structure. To assess thecosts of the INational EarthquakeHazard Reduction Program (OVEHRP)Seismfic Provisions, the BSSC in 1985contracted seventeen design firmsfrom nine U.S. cities to perform twodesigns for each of several typicalbuilding types, first using theexisting local code and then usingthe seismic provisions. They foundthe average increase in total costs tobe 0.7 percent for low-rise residentialbuildings, 3.3 percent for high-riseresidential buildings, 1.3 percent foroffice buildings, 0.5 percent forindustrial buildings, and 1.7 percentfor commercial buildings. Citieswith previous seismic designprovisions in their codes averagedmuch smaller cost increases (0.9percent) than did cities wvith noseismic codes at all.
A 1992 study by the NationalAssociation of Home Builders(NAUB) for the Insurance ResearchCouncil examined the incrementalcosts of building single-familyresidences to 1991 NEHRP Provi-sions. They found that "builders can
construct houses providing for lifesafety in earthquakes at a veryreasonable added cost-less than 1percent of the purchase price of anew home in most instances."
All Three Mode) Codes ContainSeismic RequirementsAppropriate to the Community'sLevel of Risk
Each model code contains a seismichazard map, based on currentscientific knowledge. Its risk phi-losophy is accepted by a broadconsensus of scientists and designand construction professionals. Itsuse in seismic design was deter-mined by a nationwide consensusprocess conducted by the BuildingSeismic Safety Council (BSSC), anorganization of more than fiftyconstruction, professional, and tradeorganizations.
Portions of thirty-nine states areconsidered to have some degree ofearthquake hazard. So-me countiesneed to design for high levels ofearthquake ground-shaking,Whereas others should design forrelatively less. Conversely, someareas, even those with seismic codes,do not need seismic design at allbecause the risks are so low.
Since 1992 all three model codesrequire seismic design standardsconsistent with the IVERP Prov-sions. ICBO has long been a leader inseismic code development BOCAincorporated the 1988 NEHRPPrevisions into the 1992 BOCASupplement; and SBCCI for the firsttime incorporated seismic designprovisions in the 1992 amendmentsto the SBC. Thus, all communitiesthat adopt the most recent editionsof these codes have the mostadvanced seismic codes available.
Handout H
FEMSA,Seismnic Code Workshop
Seismic Code Workshop FEMA
* Seismic Codes Are Inexpensive
Seismic codes add relatively little tothe costs of a structure. To assess thecosts of the Nationial Earthquak-eHazard Reduction Program? (NEHRP)Seismnic Provisions, the BSSC in 1985contracted seventeen design firmnsfrom nine U.S. cities to perform twodesigns for each of several typicalbuilding types, first using theexisting local code and then usingthe seismic provisions. They foundthe average increase in total costs tobe 0.7 percent for low-rise residen-tial buildings, 3.3 percent for high-rise residential buildings, 1.3 percentfor office buildings, 0.5 percent forindustrial buildings, and 1.7 percentfor commercial buildings. Citieswith previous seismic designprovisions in their codes averagedmuch smaller cost increases (0.9percent) than did cities with noseismic codes at all.-
A 1992 study by the NationalAssociation of Home Builders(NAHB) for the Insurance ResearchCouncil examined the incrementalcosts of building single-familyresidences to 1991 N\/EHRP Provi-sions. They found that "builders canconstruct houses providing for lifesafety in earthquakes at a veryreasonable added cost-less than 1percent of the purchase price of anew home in most instances."
Costs of seismic design can vary.It is easier to provide seismic designfor simple-shaped structures, withbasic geometric shapes such as asquare, and cheaper to do it ifseismic considerations are inte-grated into the earliest stages ofbuilding design. In certain situa-tions, the costs for the structure arerelatively small in proportion to thetotal project costs. This occurs if theproject has expensive contents orhigh land values. If this is the case,the cost of seismic-resistant design
Studies Indicate That the BenefitsOutweigh the Costs
A few studies have attempted tolook at the costs and benefits ofseismic design provisions. Thestudies generally indicate that thecosts of seismic-resistant construc-tion are justified.
A 1992 study, Physical Damage andHumian Loss: The Economfic lImpact ofEarthquake Mitigation A'easures,funded by the National Committeeon Property Insurance (nowse IBHS),analyzed the estimated costs andbenefits of seismic building codesfor Memphis, Tennessee, assumingdamage from magnitude 6 and 8earthquakes in the southern NewMadrid fault zone. It found thatbenefits exceed costs by a factor of1.8 for the magnitude 6 event and10.3 for the magnitude 8 event.Moreover, the b enefit-cost ratioavreraged over a forty-year timehorizon, accounting for the expectedprobability of earthquakes in thattime period, was estimated at 3.3.Thus, the expected damage overforty years is more than three timesgreater than the costs of building tocode. Furthermore, the benefits areunderestimated because they do notaccount for the benefits of reducingfatalities, injuries, fire potential, oreconomic losses. This recent studyprovides valuable analytic supportto the claim that seismic buildingcodes are cost-effective, even in thecentral United States.
Handout I
FENVIiSeismilc Code Worksh~op
Seismic Code Workshop
Group Exercise #2:Responding to Arguments Against Seismic Codes
1. list the local arguments against seismic codes:
2. How might you respond?
3. Who is likely to oppose having seismic codes?
4. Who is likely to support having seismic codes?
Handoutj
FEMIA
Seismic Code Workshop
* Arguments in Favor of Seismic Codes
For elected officials: A damagingearthquake can occur during yourterm of office. The levels of ground-shaking represented on the code'sseismic hazard map have a 0.8percent chance of occurring in anyfour-year period at each point on themap (such as the community inquestion),-and about a 2 percentchance of occurring in any eight-year period. But these are the designeveents. What about a lesser earth-quake? An earthquake half as big asthe design event could cause severedamage to many structures notmeeting the code and little damageto structures built according toseismic code. Such an event hasabout a 4 percent chance of occur-ring in any four-year period andabout an 8 percent chance in aneight-year period.
For elected officials: Citizenssupport seismic codes. Studies inCalifornia and the central UnitedStates have shown that most citizenssupport seismic building codes, andthat elected officials underestimatethis support. For example, in 1984Arizona State University surveyedresidents and officials in the highseismic risk area surrounding theNew Mfadrid fault zone. The surveyfound that 62 percent of residentsbelieved that seismic building codesfor new structures are "very impor-tant,' and most supported codeseven if substantial costs would beinvolved. In contrast support bycommunity leaders was much lowerat 37 percent. Furthermore, otherstudies have shown that communityleaders greatly underestimate thepublic's concerns about earth-quakes, mistakenly believing publicconcern to be less than their owvn.
In a 1994 telephone survey ofresidents in six hurricane-proneareas, 91 percent of respondentsindicated that builders should berequired to follow new, stricterbuilding codes even though it mightadd 5 percent to the cost of a home.
Codes will not hurt business.Building codes have not hurt theeconomies of the forty-one statesthat have them, nor have they hurtthe 95 percent of all U.S. cities andtowns that have codes. Seismicdesign adds only approximately 1 to1.5 percent to the cost of a building,according to a 1985 Building SeismicSafety Council (BSSC) study.
Is there a chance that localbuildings will be shaken by anearthquake at some point? Anearthquake can devastate the smallbusinesses in a comnuunity. Foliow-ing the 1994 Northridge, Californiaearthquake, thousands of smallbusinesses had to relocate or. tempo-rarily shut dowvn. Such interruptionscan be fatal to small businesses.Simply the loss of business activitycan affect neighboring businessesthat are fortunate to survive theearthquake ground-shaking.
A seismic code will improvesuccessful survival of the nextearthquake. People will live andwork in these buildings. Codeswork. Look at the evidence ofrelatively low loss of life in theearthquakes in California in 1989and 1994. Either a community isdesigned to survive the next earth-quake, or it is not.
Everyone else is doing it. Thefederal government has set anexample with Executive Order12699. Seismic codes are becomingmore prevalent at all levels ofgovernrment, w'hich means two
things: (a) a community -will not beat an economic disadvantage forattracting new business and (b) ifother communities adopt seismicprovisions, those that do not havethis safeguard in place inviteliability
It's easy. It doesn't take much tostart. Call up a code organization,buy the code, develop a fee structure(to pay for administration, andcontract with the county or anothernearby agency for initial staffing.
It's good for the community.AWVith a seismic code, residents willknow that the community is on itsivray to seismic safety. The code willreduce long-tern liability costs. Agood -code may ultimately improvethe community's insurance rating. Aseismic code is not an admission ofcommunity veakness, but rather asign of community strength. It saysthat the community values safetytakes itself seriously, and wants tosurvive natural disaster. All commu-nities need a seismic code regardlessof hazard. Seismic codes supplied bythe building code organizationsaccount for the unique level ofhazard in each community. If acommunity's hazard is low , the codewill reflect that. The seismic hazardzone map is based on the latestnational scientific evaluation ofearthquake risk, representing theconsensus of a number of scientificand professional organizations. Thecode requirements for each commu-nity reflect that estimate of hazard.
Handorat K
FENLA
Seismic Code Workshop
* Enforcing the Seismic Code:A Critical Link
Poor Code Enforcement Resultsin Deficient Buildings
Recent studies following HurricanesHugo and Andrew have shownweaknesses in code enforcement. In1991 State Farm Insurance Companycontracted with SBCCI to evaluatecode compliance in twelve ran-domly selected coastal communities.They found that inspectors andreviewers had little Or no training inwind-resistant construction and thatthere was a general lack of enforce-ment of adequate connections ofwindovs, doors, and mechanicalequipment to the building frame.About half of the communities were
- 4 .3 - - 4 t-.I.34
Insurers and lenders have begun to realize that adoption and enforcementof building codes in general, and seismic codes in particular, are in theirlong-term interest. Accordingly, in 1995 the Insurance Services Office,Commercial Risk Services (ISO/CRS) began to phase in a new BuildingCode-Effectiveness Grading Schedule. By the end of the decade, thisschedule will rate the code-enforcement capabilities of every municipalityin the United States.
The insurance industry is developing this new grading schedule toreward communities for promoting property and life safety protectionthrough the use and enforcement of modem codes. The system will be usedby property insurers to set differential rates among communities based oncode-enforcement practices. Property owners in communities with goodcode enforcement will pay lower insurance premiums-and owners incommunities ivith poor enforcement will pay more.
The grading schedule measures resources and support available tobuilding code enforcement efforts. It assesses each municipality's supportfor code enforcement, plan reviewv, and field inspection. The gradingprocess includes interviews with municipal officials, examination ofdocuments, review of training requirements and work schedules, staffinglevels, and certification of staff members.
The new system is comparable to the fire protection grading system andthe community rating system for flood insurance already used by ISO/'CRS.These two systems use a rating scale of one to ten, with one representing thebest protection and ten indicating no protection.
For more information, contact the coordinating body, the InsuranceInstitute for Property Loss Reduction.
not enforcing their own codestandards for wind resistance.
Following Hurricane Andrew,reports by a Dade County grandjury and by the Federal InsuranceAdministration concluded that asubstantial portion of the storm'sdamage was attributable to lack ofenforcement of the South FloridaBuilding Code. According to theInsurance Services Office, Inc., atleast one-fourth of the record $15.5billion in insured losses caused byAndrew were because of construc-tion that failed to meet DadeCounty's code. Thus, even incommunities with adequate codes,significant damage can be attributedto poor compliance and enforce-ment.
In a 1993 study, G.G. Schierle -ofthe University of Southern Califor-nia found significant problems inquality control of seismic-resistantconstruction in California. By meansof a survey of design professionalsand site inspection of 143 projects,the researchers found that key itemsto resist seismic load are frequently(13 to 72 percent of surveyed units)missing or flawed. Reasons indlude"inadequate communication, little orno construction observation bydesign professionals, ignorance,greed, shortsighted false economy,and lack of scrutiny by buildinginspectors."
Clearly, much effort needs to bespent on improving code enforce-ment. The weaknesses becomeapparent only at the moment whenresistance is most needed-whenthe disaster strikes.
Handout L
FEWL
Seism~ic Code Workshop
Five Elements of Effective Code Enforcement
Code enforcement and administra-tion consist of five sequentialelements.
Element 1: Keep the CodeProvisions UP To Date
Simply adopting a code is notenough. A code is an active docu-ment, evolving to reflect newknowledge and new standards ofpractice. Once a jurisdiction makes acommitmnent to use a building code,it must be prepared to update itslocal code on a regular basis.
Element 2: Ensure That BuildersApply for Permits
Obviously, if builders try to avoidthe code-application process, thenthe code cannot do its job. A juris-diction must have inspectors out inthe field who know the community.The inspector needs to be alert tonew construction in his Or herjurisdiction and must be aware ofcurrent active permits.
In addition, the building depart-ment must cultivate and maintaincordial relations with the buildingand design community. This can bedone by arranging informal meet-ings, sending written materials tolocal organizations, speaking tocommunity groups, and maintainingmemberships in appropriate tradeand professional organizations.
Element 3: Have a QualifiedReviewer Review Plans
Plan review is one of the two pointsat which the local government canaffect the details of building con-struction. At a minimum, planreview verifies that the designcomplies with the building code.This is the most cost-effectivemoment to catch mistakes, beforeany money is spent on construction.Some jurisdictions may also reviewstructural calculations.
Plan reviewers must be fullyknoxwledgeable about code require-ments. Some jurisdictions uselicensed architects and engineerswho can go beyond code compli-ance reviewvr and verify calculationsand overall building safety. Thebuilding department can approve,require revisions, or reject the plans.Construction cannot begin until thebuilding department confirms thatthe plans conform to the buildingcode.
Construction of buildings largerthan one- or two-family dwellingsusually requires architectural andengineering designs. State statutesrequire that the licensed professionalengineer and/or architect place hisor her seal and signature on thedesigns. The seal and signaturesignify that the design is at theaccepted professional standard,which is typically the most recentversion of a model building code ortechnical document.
Element 4. Ensure ThatConstruction Proceeds Accordingto Approved Plans
An owner receives a building permitto construct according to the ap-proved plans, and it is the legalresponsibility of the owner to do so.The owner may hire inspectors or
the engineers and architects tooversee key aspects of the construc-tion in order to help verify compli-ance with the plans. To some extent,all government inspection systemsdepend on this obligation by theowner, which is inherent in theissuance of a permit.
Element S: Have a QualifiedInspector Inspect theConstruction
Inspection is the second point atwhich the local government canaffect the details of building con-struction. Inspection verifieswhether construction is proceedingaccording to the approved plans andthe conditions of the permit. Irnspec-tion is typically required at severalkey stages in the constructionprocess. The inspector has a power-ful enforcement tool called a stopwork order. A stop work order isissued to the construction firm if theinspector finds a code violation thatmust be corrected before any furtherconstruction is performed. At finalinspection, the building can beapproved for occupancy.
Depending on the jurisdiction,inspectors may be municipalemployees or contracted trades-people. in either case, buildinginspectors must be whell qualified.They must know hol r to readbuilding plans and must be familiarea.th the code. More importantly,they must be familiar with buildingpractices so they can recognizepotential problems. Model codeorganizations offer certificationprograms to recognize the capabili-ties of inspectors.
Handout M
FEMA1
Seismic Code Workshop
Group Exercise #3a:Action Plan to Adopt a Building Code
Develop a ten-point action plan that will result in a building code (with current seismic provisions!).
for this community:
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ifJ.
FEMA
Handout N
Seismic Code Workshop FEW
Group Exercise #3b:Action Plan to Improve Code Enforcement
Develop a ten-point action plan that will result in improved code enforcement for thiS coMmunity:
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Handout 0
Seismic Code Workshop
Steps Toward Adopting Seismic Code Provisions
Step 1: Determine Code Practicesand Options
e To whatever extent the stateregulates construction, satisfyyourself that enforcement isadequate.
• If the state mandates local adop-tion of a specified code, ensurethat the community has com-plied.
• If the state does not currentlyregulate, or if it allowvs for stricterlocal regulations, gather informa-tion on local code practices andexplore options at the local level.
• Options may include developingan original code, modifying anexisting code, or adopting amodel building code.
If a jurisdiction lacks an adequatecode, work to initiate a buildingcode.
* Model codes are usually the bestoption, because of the technicalsupport provided by the codeorganization.
Step 2: Gather Support
W V ork with state officials
*Work with the professionalassociations of engineers andarchitects
* Contact ciric groups and serviceclubs, relevant businesses andconstruction organizations,chambers of commerce, economicdevelopment associations, and soforth
* Cultivate the media to helpeducate the general public
Step 3: Lobby the Decision-Making Body
a Explain why the changes areneeded and describe the kind ofsupport you have gathered.
• Gain the support of thegovemor's office.
* Consider educational programsor incentive programs that willappeal to governmental officials
* Consider ways of subsidizing thecost of joining a model buildingcode organization
• Monitor the process frombeginning to end
Step 4:Assist Throughout theAdoption, Implenmentation, andEnforcement Stages
E Provide information aboutseismic hazards in the area, thefunction and effectiveness ofseismic codes, elements of codeenforcement, and services pro-vided by the model code organi-zations
a Keep informed of implementationmilestones
e Meet periodically with thebuilding official(s)
* Verify that adequate procedureshave been introduced for planreviewxT, inspection, and stafftraining
• Inform the building officials ofany problems
Handout P
FEMA
Seismic Code Workshop FEA'¶A
* Steps for Enforcement of Seismic Codes
This section outlines the six stepstoward establishing an effectivebuilding code program.
Step. I:Adopt a Model Code
The first step in establishing aprogram is to review^% and adopt amodel building code and join theappropriate code Organization.Numerous publications and tele-phone-assistance services will thenbe available to help the new pro-gram get started. The informationprovided includes organizationcharts, descriptions of staff duties,fee structures, suggested proce-dures, and so on. Ne; membersmay wevant to take seminars in planreview and inspection beforeofficially initiating the code.
NewN, members can request themodel code staff to visit and assist inestablishing their program. Ifextensive help is required, the codeorganization may be hired toprovide the needed assistance. It iseasy to get started, because the codeorganizations are set up to effec-tively and efficiently provide all thesupport you need.
Step 2: Establish Fee Structuresfor Permits and Plan Review
Building departments collect fees topay for the costs of review, inspec-tion, and associated administrativeservices. The community sets the feestructure based on its needs. Somecommunities require the buildingdepartment to be completely self-supporting; others use the fees tooffset only a portion of their truecosts. Communities with significantexperience in code administrationcan set fees based on previousbudgets. Communities just starting
out may prefer to use the fee struc-tures suggested by the code organi-zations.
Plan review fees typically arebased on estimated constructionvalue, which depends on buildingfloor area, type of construction, andproposed use. For example, underthe BOCA NBC, the suggestedbuilding plan review fee for $1million construction value is $1,250.Review for mechanical work,plumbing, energy conservation, orelectrical work is an additional 25percent each (i.e., each of theseadditional reviews, if required,costs $312).
Step 3: Institute a SystematicPlan Review System
Plans usuallyamust be circulated toseveral additional departments forrevie'w, such as the planning, publicw orks, and fire departments. It isbest to have one department desig-nated as the lead and to requiremultiple plan copies from theapplicant so as to facilitate multi-department reviews.
Applicants should be kept wellinformed right from the start.Handouts and checklists are veryimportant so that they know whatmaterials to submit and how theplan will be judged.
Step 4:Adopt an InspectionSchedule
Each code has a recommendedinspection schedule based onconstruction milestones. For ex-ample, the BOCA NBC suggests thefollowing inspections for residentialbuildings: footing forms andtrenches, basement and foundationwall forms, footing drains and dampproofing, framing, wallboard, andfinal. Similar schedules exist for
electrical and mechanical w ork andplumbing.
Typically, the builder or ownerwill call for inspection when eachspecified milestone is reached. Inaddition, inspectors occasionally.make unannounced inspections'based on their judgment of the workprogress and the quality of thecontractor.
Step 5: Maintain a Trained,Qualified Staff
Ideally some staff members wouldbe licensed engineers and architects,but most departments are too smallto justify this cost. At a minimum,reviewers and inspectors must haveexperience in construction, be ableto read plans, and be familiar withthe code. Each of the model buildingcode organizations offers certifica-tion in a number of categories forinspectors and plan reviewers. Moreand more building departments arerequiring or rewarding certificationin order to recognize staff qualitylevels.
Step 6.: Be Persistent But Patient
You need to realize that a new codewill not be implemented in one day.Adequate enforcement takes manyyears of -experience and learningfrom mistakes. Procedures evolveover time. Building officials, planreviewers, and inspectors mustreceive technical training andcontinuing education, which cannotbe done overnight. Yet the effort isworth it, as seismic codes affordcomrmunities a high degree ofimproved building safety.
Hondout Q
FEMASeismic Code Workshop