Van Turkey Eq-report

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EERI Special Earthquake Report April 2012

Learning from Earthquakes

The Mw 7.1 Erci-Van, Turkey Earthquake of October 23, 2011

The following EERI reconnais-

sance report on the 23 October

2011 Erci, Van, Turkey earth-quake has been prepared byRafael Alaluf of EQRM Interna-tional Inc., Ricardo Hernandez ofDegenkolb Engineers, CemalettinDnmez of zmir Institute ofTechnology, and Ayhan rfanoluof Purdue University. Funding fortravel for these team memberswas provided by the individualauthors, EERI, the zmir Instituteof Technology, and the George

E. Brown, Jr. Network for Earth-quake Engineering SimulationOperations Center, NEEScomm.In preparing this report, as ref-erenced in the text, the writersbeneted from the work of severalof their colleagues who visitedthe disaster area and generouslyshared information. In conductingthe eld work, the authors alsocollaborated with the EarthquakeEngineering Research Centerof the Department of Civil Engi-

neering at Middle East TechnicalUniversity, and the Van YzncYl University. See acknowledge-ments for a complete listing.

Introduction

At 1:41 pm local time on Sunday,October 23rd, 2011, a Mw 7.1earthquake struck Van Province ineastern Turkey (USGS, 2011). Theearthquake claimed 604 lives. Thetown of Erci, with a population of77,000 (GOVP, 2011), was hit hard-est. Located about 40 km NNW of theestimated epicenter, it had 191 build-ings collapse totally or partially, killingmore than 600 people. Van, the largerprovincial capital located about 15 kmSSW of the estimated epicenter, was

mostly spared, with only six build-ings collapsed. On November 9th at9:23 pm local time, a Mw 5.6 earth-quake struck about 10 km SW of Van(AFAD, 2011). This event claimed 40lives and caused further damage inthe city of 332,000, including collapseof 25 buildings, most of which hadbeen condemned following the earlierearthquake.

Seismotectonics

The region around Van has a complexseismic setting due to the interactionbetween the Arabian and the Eur-asian tectonic plates. The area haseast-west thrust fault zones, as well

as northwest-southeast right-lateraland northeast-southwest left-lateraltranslational fault zones (METU,2011a) (see Figure 1).

The main shock is believed to havebeen on a WSW-ENE reversefault with north-dipping fault plane(METU, 2011a) (Figures 2 and 3);the fault was not identied on theactive fault map of Turkey (MTA,1992). The November quake isbelieved to have occurred on astrike-slip fault also previouslyunidentied.

The largest earthquake recordedin the region during the last cen-tury was the 1976 M7.2 aldranearthquake (Gulkan et al., 1978),although the 1945 M5.8 atak,1972 M5.2 Van, and the 1977 M5.1Erci were signicant as well.

The strong ground motion station inVan did not record the ground shak-ing from the October main shockdue to a malfunction. The closest

station that recorded motion wasthe Muradiye station (38.99011N,43.76302E), approximately 40 kmNNE of the epicenter. Unprocessedrecords (Figure 4) indicate peak

Figure 1. Above: Van and Erci are located in eastern Turkey byLake Van (source: BBC, 2011). Right: fault zones around LakeVan (source: METU, 2011a).


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ground accelerations were 178 gal(N-S), 170 gal (E-W), and 80 gal(U-D). Acceleration response spec-

tra are shown inFigure 5. It is believed that Ercihad ground shaking stronger thanthat in Muradiye. The station in Vanrecorded the November groundmotion with peak accelerations(unprocessed) were 148 gal (N-W),246 gal (E-W), and 151 gal (U-D).The original and processed recordsfrom the October main shock canbe found on http://eerc.metu.edu.tr/, and in METU, (2011b).

Performance of Structures

The seismic hazard map of theprovince (Figure 6) comprises

the top two highest seismic hazardzones in Turkish earthquake-resistant

design. The northern and southernthirds of the province are consideredas seismic Zone 1, with effectivePGA for design calculations equal toor higher than 0.4 g. Erci is in thenorthern third of the province. Themiddle third of the prov-ince, which includes Van,is considered as a seis-mic Zone 2, with effectivePGA in the range of 0.3gto 0.4g.In 2000, following the

devastating 1999 Mar-mara earthquakes,Turkish state authoritiesissued an ordinance oncontrol of private build-

ing construction.However, theordinance wasstricken down bythe ConstitutionalCourt withinten months, asetback thathindered estab-lishment ofindependent andeffective controlmechanisms. In2001, the Turk-ish Governmentpassed a Build-ing Control Lawfor privately built

buildings; 19 of the 81provinces were chosenas pilot districts toimplement the 2001 law,but Van was not one ofthem. Only on January1, 2011, did the Build-ing Control Law go into

effect in Van province,along with the rest of thecountry. It is believedthat the 2001 BuildingControl Law will helpimprove the quality ofconstruction as it estab-lishes control authoritiesand prohibits uncheckedconstruction. There arereports that 89 of the

buildings in Van province that werebuilt under the Building Control Law

performed very well (Eyidogan,2011).

Building stock and construction

type. The dominant types in theregion are one- to nine-story rein-

Figure 3. Distribution of slip over the estimatedfault plane. The arrows indicate the directionof motion of the hanging wall relative to thefootwall (source: Hayes, 2011).

Figure 4. Main shock uncorrected ground accel-eration records from the Muradiye station (source:METU, 2011b).

Figure 2. Fault model for the Mw 7.1 earthquakeshowing the hypocenters of the main shock andaftershocks (source: Hayes, 2011).


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forced concrete (RC) buildings withinll walls and moment-frame ormoment-frame and structural walls,and one- to two-story bearing-wallbuildings. Buildings constructedbefore 2000 tend to be one tofour-stories high. The majority ofthe buildings have full or half-base-

ments. With the population growthin the provincial capital (Figure7) and the economic boom in theregion over the last decade, manytaller buildings of eight to 12 storieshave been put up in Erci and Vanin recent years. In Erci, wherenearly 200 buildings collapsedtotally or partially, most of thecasualties occurred in the newerand taller buildings. We learnedfrom local engineers that ready-mix concrete became available inthe last 3-4 years, and that therehas been widespread use of poorlywashed sand and gravel from localcreeks. Inspecting the debris of col-lapsed structures showed a numberof deciencies: insufcient conne-ment reinforcement and 90-degreehooks in transverse rebars, use ofsmooth rebars, improper splicingof column longitudinal reinforcingbars, poorly graded concrete mixdesign, and substandard concrete

casting (Figure 8). Apparently, thenew RC structures were designedby engineers, but they had no qual-ity control during the actual con-struction of the building. Our localcontacts noted that the constructionprocess had become so informalthat land owners would hire sepa-rate local specialty workers (forformwork, rebar placement, con-crete casting) and not even hire acontractor to organize the process.Few, if any, inspections or quality

control checks were done.

The widespread poor material useand construction quality do notexplain the variation in damage inthe building stock. We observedthat a majority of the damagedbuildings suffered from obviousfundamental design errors such asinadequate lateral-load resistingsystems, soft-story at ground level

Figure 5. Response spectra for the N-S and E-W records for the Muradiyestation motion (unprocessed) recorded during the main shock (source:METU, 2011b).

Figure 6. Seismic hazard map for Van Province (MPWS, 1996) withepicenters of the October and November earthquakes.

October 23r

Event

November 9th

Event

Zone 1

Zone 2

Zone 3

Zone 4

Zone 5


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opment Administration of Turkey,sustained no damage.

Even though there are no groundmotion records from Erci or Van

for the October event, it is believedthat the levels of ground shak-ing in these towns were such thatarchitectural inll walls, in general,assisted the actual lateral load-resisting structural systems inthe buildings. However, in certaincases, these supposedly nonstruc-tural walls interacted with the struc-tural systems to the detriment ofthe latter by forming captive columnconditions either from the beginningof (Figure 12) or during the dynamicresponse of the building (Figure13). In adjacent buildings withinsufcient separation, poundingdamage was observed (Figure 14).

The typical oor structural systemsin the RC structures are two-wayslab systems and inll joist oorsystems (Figure 15), the latterbeing found mainly in buildings builtin the last ve years.

There is a tendency to have struc-tural walls in ve-story or tallerbuildings constructed recently.However, we observed new orunder-construction buildings withimproperly positioned structuralwalls that resulted in oor torsion.One nearly completed building(Figure 16) had a single largestructural wall on the back that cre-ated oor torsion, and block-inll

Figure 10. Heavily damaged RCstructure with tall ground story(photos: Dnmez, rfanolu).

Figure 11. Six-story + basement RC moment-frame and structural wall build-ing in Erci. The relatively taller ground story has a mezzanine level wrappedaround the elevator core structural walls. The core structural walls parallel tothe building front sustained heavy damage, but there was no damage in thecolumns (photo: rfanolu).

Figure 12. Erci inter-city bus terminal. Partialheight inll walls alongthe side of the building atthe ground story causeda captive column condi-tion. The captive columnsfailed and the buildingwas put out of operation(photo: rfanolu).


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joist oors which were too exiblecompared to the columns. Therewas concrete crushing and/or shearfailure at lower ends of almost

every column at the ground story,and exural failure at the endsof the perimeter beam installedalong one edge of the building.Furthermore, cracks developedat column-joist oor interfaces atevery oor level, and a web ofcracks spanning between columnlines was observed in the joist oorslabs at every oor level (Figures16 and 17). The concrete strength

of the structure was determined tobe around 30MPa with a SchmittHammer. Even though deformedbars were found in the columns,almost no connement reinforce-ment was observed at the plastichinge regions.

There are few buildings withstructural walls. Except in some ofthe school buildings, which will bediscussed below, structural wallswere usually not adequately propor-tioned. Still, walls around elevatorshafts did tend to reduce damage tothe rest of the structure though theysustained considerable damagethemselves.

In Gedikbulak, a large village with250 buildings located about 15km NW of the October earthquakeepicenter, a three-story primaryschool building with structural wallscollapsed during the earthquake(Figure 18). The building, con-structed in 1988, had an approxi-mately 14.4m x 21.4m footprint.It had two 7.2m x 0.3m structuralwalls along its plan long directionbuilt on one end of the building andonly columns, some of which werecaptive, at the other end. Two 4.6m

x 0.3 m structural walls borderingthe stairwell, which was near thecenterline, acted as the main lateralload-resisting elements in the planshort direction. The seven 0.5m x0.3m columns around the buildingperimeter were the sole verticalstructural elements along one halfof the building front, although four0.3m x 0.3m interior columns werealso present. The collapse congu-ration evidenced oor torsion as itappeared that the building twisted

in plan as it slumped.

Buildings in low-income districts inthe region are typically constructedeither with concrete masonry unitsas bearing walls for single-storybuildings, or with reinforced con-crete frames with masonry inll forup to two-story buildings. Thesestructures commonly have lighttimber roofs with light gage metal

Figure 13. Hollow concrete masonry units failed during the earthquake andcaused a captive column condition. The column experienced brittle failure inshear (photos: rfanolu and Erdil).

Figure 14. Pounding damage inVan (photo: rfanolu).

Figure 15. Joist-oor systemin buildings under constructionin Erci. The inll used in theoor system in the top photo isconcrete masonry block, on thebottom polystyrene foam (photo:rfanolu).


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but it was due to discontinuity in theexural reinforcement. The exist-ing (original) structural walls of thestructure in the N-S direction had adiagonal web of hairline cracks up

to the third story. There was sepa-ration at the interface between theadded structural walls and the perim-eter framing, particularly the beam towhich the added structural reinforce-

ment wasanchored. Thedamage pat-tern indicatesthat the addedshear walls didnot engagewith the exist-

ing structuralframe rightaway.

The VanMerkez skele

District Boarding School classroombuilding is similar to the school inFigure 22. The two-story RC build-ing had diagonal nets of hairlinecracks in some of its original struc-tural walls. There were also signsof separation between the added

structural walls and the perimeterframing, particularly at the wall-upper beam interface.

Reportedly, the Van branch build-ing of the Turkish Central Bank hadbeen reviewed for possible seismicstrengthening, but that had beendeemed unnecessary (Figure 23).This very irregular ve-story build-ing has a three-story atrium andwing walls at the perimeter as the

primary structural elements of thesystem. No structural failure wasseen in the system except for acrack on one of the beams; how-ever, extensive partition wall failurein the building disrupted services.

Government buildings. Structuralsystems in government buildingsvaried depending on the age of thestructure. The spectrum stretchesfrom stone bearing-wall systemsin old structures to RC frames in

relatively new structures, but RCframes predominate. They are sub-ject to special regulations depend-ing on the ministry with which theyare associated. The Erci Palaceof Justice is an example of the oldbearing-wall systems. As shownin Figure 24, cracks formed in thewalls and went through concretelintels within the walls.

Figure 21. Local branch of Ziraat Bank which was seismically strength-ened before the recent earthquakes (photo: Alaluf).

Figure 19. Typical out-of-plane failure of concrete masonry unit bearingwalls (photos: Alaluf and Bedirhanolu).

Figure 20. Failure of mud brick bearing walls in Gedikbulak village(photo: rfanolu).


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The Erci District Governors Ofce,a campus of two- to ve-story plusbasement modern RC buildings withframe and structural wall systems,sustained no structural damage andonly minor damage in nonstructuralwalls. The main problems werefailed water tanks in the basement,

collapsed archive support systems(Figure 25), and ceiling tile failure inthe conference hall on the top oor.

Primary/secondary educa-

tion buildings. Primary schoolsinspected in both Van and Erci hadin-plane and out-of-plane damageto the hollow clay tile inll walls andminor structural damage in some ofthem. Many schools had crackingat the frame/wall interface, diagonalcracks, through-cracks, and crush-

ing of the inll walls. Out-of-planegable wall failure was typical in allof the schools that were observedthroughout the area.

At the Cumhuriyet Primary School(Figure 26), a conglomerationof four-story buildings locatedapproximately 0.5 km southeastof the collapsed building (Sevgi

Apartman) that claimed 50 lives inthe city center of Erci, there was

only minor damage to the structuralsystem. Except for a corridor inwhich the inll walls were crushed,minor to moderate damage to theinll walls with cracking at the wall/frame interface.

At the Atatrk Primary School,approximately 0.5 km northwest ofthe Sevgi Apartman building, athree-story plus basement schoolbuilding had out-of-plane gablewall failure, but the building was

in a good enough condition for themilitary to use it for response opera-tions.

Near the Van pier, a three-storybuilding used as a teachers resi-dence had out-of-plane wall failure.

Figure 22. Kazim Karabekir Primary School in Erci. Interface crackbetween the added RC structural wall and the original beam (photo:rfanolu).

Figure 23. The Van branch buildingof the Turkish Central Bank (photos:Dnmez).

Figure 24. Severe damage towalls of Erci Palace of Justice(photos: METU group).


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Above the third-oor ceiling slab,the structure consisted of woodpost/beam framing supporting theroof with a story height equivalent to

the oors below. The wood-framedportion had wood diagonals placedsystematically to provide stability.On two sides of the structure at theuppermost story, out-of-plane wallfailure was observed (Figure 27).

Universities. Van Yznc YlUniversity, established in 1982with a population of approximately18,500 students, is located approxi-mately 20 km from the epicenter ofthe October earthquake. Overall,

campus buildings performed wellfrom a structural point of view, withmost buildings having only minorto moderate damage to the hollowclay tile inll walls. The library, ave-story building with an irregu-lar footprint and obvious inferiorconcrete quality and reinforcement

detailing, sustained the most damageand is currently out of commission.The damage appeared to consistprimarily of an out-of-plane collapseat a gable wall and the exterior wall

at the exit stair well, heavy structural

damage at the stairs and somebeams in the structure (Figure 28).

A few buildings were deemed torequire further investigation, whileothers had only a little nonstruc-tural damage with some crackingat the wall/frame interface.

The Medical School of the univer-sity is not on campus but in Van,with seven main blocks intercon-nected to each other. Four of theseblocks were built 60 years ago.The other blocks were built in thelast 15 years. All of the blocks areRC structures with two-way slabsystems. Even though the over-all construction quality was notgood, no structural damage wasobserved in the buildings after the

October earthquake. However,

Figure 27. Teachers housing in Van near the pier (photo: Hernandez).

Figure 28. Library building at VanYznc Yl University (photos:Dnmez).

Figure 25. Archives in Erci DistrictGovernors Ofce (photos: rfanolu).

Figure 26. Cushed inll walls inCumhuriyet Primary School in Erci(photo: rfanolu).


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due to medium to heavynonstructural damage,the university hospitalwas out of service. Thenonstructural elementsand contents thatrendered the hospitalinoperable were partitionwalls, molded gypsumornaments at the ceil-ings, wall panels on topof partition walls, andlaboratory glasswareand hardware. The uni-versity was closed untilFebruary 2012.

Mosques. Construc-tion of the mosques weobserved generally con-

sisted of concrete framewith hollow clay tile inllin the prayer hall andstone cladding in theminarets (see Figures 29and 30).

The prayer halls of mostmosques in Erci andVan had little damage,largely minor diagonalcracks and/or cracksat the interface of the

inll/frame, althoughthe Kara Yusuf Paamosque in Erci sus-tained heavy damage in

its main structure (Figure31). Minarets had dam-ages that ranged from

minor cracks in the shaft, toppled

end ornaments, and toppling of theminaret just above the transitionsegment. Figure 32 shows that thetoppled minaret punched throughthe elevated concrete slab abovethe ablution room.

At the Salihiye Mosque on the north

side of Erci, one of the minaretsfailed just above the transition zoneand toppled southward, damag-ing the dome of the prayer hall.The other minaret showed signs ofincipient failure well above the tran-sition zone. In Gedikbulak, the localBlbl Mosque collapsed totally(Figure 33).

Hospitals and health-care

facilities. There is a wide range

of hospital buildings in both Erciand Van. The Erci State Hospi-tal, constructed in 1962 with vebuildings, has a current capacityof approximately 134 beds. It islocated approximately 100 m fromthe Sevgi Apartman. Most buildingson the campus are two- to three-story reinforced concrete build-ings. Discussions with the securitypersonnel at the site revealed thatthe building was red-tagged despiteonly minor damage. The hospital

could have played a signicant partin the emergency response had itbeen open. It received a green tagapproximately one week after theearthquake, and was scheduled toresume normal operations shortlythereafter.The Van State Childrens Hospi-

tal, located in the heart ofVan and 22 km southwestof the epicenter of the Octo-ber earthquake, consisted ofseveral three-story buildings

constructed in the 1960s. Mostof the buildings had minorto moderate cracking at theframe/wall interface, with somelocal damage due to pound-ing and inll damage. Likeits counterpart in Erci, theentire campus was closed topatients.

Figure 29. Mosque under construction in Erci(photo: rfanolu)

Figure 30. Typical Turkish minaret (source:Doangn et al., 2006).

Figure 31. Kara Yusuf Paa Mosque in Erci, built in 1974 (photos: METU group)


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The Van State Hospital is a state-of-the-art facility with several build-ings that opened approximatelyone year ago. Located 30 kmsouthwest of the epicenter of theOctober quake, it has deep foun-dations supporting the reinforcedconcrete frame building. Based on

our discussion with hospitalpersonnel, there was onlyminor nonstructural damage,such as some interior wallcracks and a partial collapseof a small portion of theexterior faade. There wasno interruption in serviceand the hospital cared forinjured immediately after theearthquake.

Industrial facilities. Indus-trial facilities in Van andErci had little to no damage

to the primary

structures. Theindustrial areaof Van is locatedapproximately20 km SW ofthe epicenterof the Octoberearthquake. Thebuilding inventoryincludes precastconcrete buildings,concrete frame

with hollow clay

tile inll walls, andsteel-framed build-

ings. Damage appeared to be limitedto a few non-building structures suchas storage bins.

At a our manufacturing plant, twoout of six small grain bins constructedof light steel framing collapsed. Dis-cussion with the owner revealed that

those bins were lled to capacity,while the others were not. The col-lapsed bins also appeared to havea cross-bracing design that did notcontinue to the base of the verti-cal legs, possibly causing them tobuckle under the seismic movement(Figure 34).

A concrete ready-mix plant, locatedjust down the street from the ourmanufacturing plant, also had astorage bin collapse. The bin wassituated atop a small concretestructure, and the vertical legs, andpossibly the cross-bracing, buckled.The only two large industrial facili-ties in Van Province are the VanCement Plant in Edremit and ErciSugar Plant. The cement plant had

no damage. The Sugar Plant--acomplex of buildings consisting ofconcrete frames with hollow claytile inll walls, steel braced frames,and prefabricated concrete framebuildings--sustained damage onlyto its administration building. Athree-story concrete frame structurewith a daylighting basement hadsome unreinforced hollow clay tilefacades fall off at several locationsand moderate inll wall damage.Neither of the plants had direct

business interruption. The cementplant was going through its regularannual maintenance, and was not inoperation. The sugar plant stoppedproduction, though it was operable,because it was selected as thewarehouse/center for aid distribu-tion to earthquake victims.

Lifelines

Highway roads and bridges.

Except for the road surface defor-mation near the epicentral regionon the main Van-Erci highway, noimpact on the roads was observed.

According to reports from theMETU-EERC and civil engineeringteams (METU, 2011a), damage inthe 14 reinforced concrete highwaybridges inspected by the teams wasminimal. Most of the bridges weremade of reinforced concrete piers

Figure 33. The Blbl Mosque in Gedikbulakvillage (photo: Alaruf).

Figure 34. Collapsed bin at our plant in provincial

capital Van (photo: Hernandez).

Figure 32. Toppled minaret at Vanyolu Mosque (photo: Hernandez).


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supporting prestressed reinforcedconcrete I-beams, multi-spanwith 17.5m typical span length,supporting the deck. Permanenttransverse offsets on the order of1-2 cm were observed at expan-sion joints, as were spalling andcracking in concrete transverseshear keys. Flexural cracks wereobserved in the piers of the Ben-dimahi bridge near Erci.

Railroad system. No damage wasreported in the railroad system,including in the railroad tunnelin the epicenter region (METU,2011a).

Airport. In the wake of the Octo-ber quake, Van airport was putback into full service after a quickinspection of the runway and thenavigation equipment. There was

Figure 35. The old and the new terminal buildings at Vanairport (photo: rfanolu).

Figure 36. Pier at Van (photo: Hernandez).

Figure 37. Transverse crack atthe Van pier (photo: Hernandez).

some glazing failurein the tower, so theoperation was movedto the re brigadebuilding and func-tioned without disrup-tion. At the time of theearthquake, the mainterminal building wasbeing dismantled tomove the airport oper-ations to the adjacentnew terminal building(Figure 35). Serviceswere provided from

the old building until the Novemberearthquake, which caused struc-tural damage to it (Cebeci, 2011).

Lake Van port. The port is con-

structed of deep foundations sup-porting a 84-m long by 14-m wideconcrete pier (Figure 36) structurewith a capacity to dock one largecargo ship on one side of the pierand several small to medium-sizedboats on the other side of the pier.From our preliminary observations,there were two transverse cracksin the pier, the rst near the begin-ning and the other approximately20 m from the end. The crack nearthe beginning of the pier did not

continue through the width of thepier, but the crack near the endwas a through-width crack. At thetime of our observation, the pierwas in use and the damage did notappear to affect its operation.

A prefabricated one-story structureused to house passengers hadminor cracking due to the spread-ing of soil in the vicinity. Smallsand boils and spreading cracksapproximately 2.5 to 3 cm wide

were visible.

Electrical transmission sta-

tions. Observations were madeat two local electrical substationsin the affected area near the cityVan. The 154-kilovolt transformercenter approximately 22 km south-west of the October earthquakeepicenter, which receives powerfrom the local Keban dam, had no


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damage although service to Vanwas interrupted for approximately3 hours due to downed powerlines in the city. A new 380/154/33kilovolt capacity electrical substa-tion located approximately 20 kmsouthwest of the October epicenterwas under construction and sched-

uled to open in November 2011.The substation reportedly had nodamage except some transformersthat shifted during the earthquake.The opening of the substation wasdelayed until the transformers wererepositioned.

Emergency Response

In the October quake, 604 peoplewere killed, about 2,600 were

injured, and 222 were rescued fromcollapsed structures during emer-gency response operations. Duringthe November quake, 40 peoplelost their lives and 30 were rescuedfrom collapsed structures near Van.

According to the Turkish Disas-ter and Emergency ManagementDirectorate (AFAD), within hoursof the October earthquake, nearly500 search and rescue, emer-gency medical and Red Crescent

personnel arrived at the disasterregion. They were mobilized from48 provinces and 39 agencies. Asof mid-December, 5,267 search andrescue and 2,976 medical person-nel from state, provincial, non-governmental, and Turkish ArmedForces had been to the disasterarea. Nearly 200 ambulances,including 18 medevac helicopter,supported the emergency medicalteams. Six eld hospitals were con-structed. Nearly 200 social work-

ers, sociologists, psychiatrists andconsultants participated in providingpsycho-social support.

As of mid-December, 73,679 tents(29,222 from abroad), 260 pre-fabricated housing units, 10,155inhabitable containers, and 3,794specially designed prefabricatedhouses were sent to the region. As

winters are harsh in the disasterregion, over 336,000 blankets,7,192 sleeping bags, and 27,500heaters were distributed. Approxi-mately 20,000 people were livingin 14 tent cities built in Van andErci. Nearly 3,500 tents weredistributed in the countryside to

shelter animals. Over 132,000meals were being distributed dailyin three central cafeterias and 35schools in the region. At the endof January, 19,500 inhabitablecontainers were providing shelterto around 100,000 people (Uras,2012). In Erci, eight soup kitch-ens served 81,000 meals a day; inVan, three soup kitchens served60,000 meals each day. Addition-ally, 72,000 meals were purchaseddaily by the state from privateproviders.

The domestic and internationalmonetary aid is estimated to beTL 411 million (approximately US$220 million). Aid was received from

Algeria, Armenia, Australia, Azer-baijan, Bahrain, Belgium, Bulgaria,Canada, Egypt, Finland, France,Germany, Iran, Ireland, Israel, Italy,Japan, Jordan, Kazakhstan, Kyr-gyzstan, Malaysia, Netherlands,

Norway, Pakistan, Qatar, Roma-nia, Russia, South Korea, Spain,Sweden, Switzerland, Syria,Tunisia, Turkish Republic ofNorthern Cyprus, Ukraine, UnitedKingdom, the USA, and the UNHCR and OCHA.

Economic Impact and

Long-term Recovery

Final damage surveys werecarried out by 1,136 technicalpersonnel between November15th and December 22nd in Van,Erci, and several other districtsand villages in the province. Asnoted in Table 1, of the 103,478buildings inspected, 33,016buildings (31.9%) were either

heavily damaged or collapsed,4,755 buildings (4.6%) sustainedmedium-level damage, 35,545buildings (34.4%) sustained lightdamage, and 30,162 building(29.1%) had no damage.

Of the 14,904 commercial unitsinspected, 2,440 (16.4%) wereeither heavily damaged or col-lapsed, 2,748 (18.4%) sustainedmedium damage, 6,307 (42.3%)sustained light damage, and 3,409

Table1.Damagedistributionininspectedbuildings(VSG,2011)

DamageLevel NumberofBuildings FractionofTotal

Heavy/Collapse 33,016 31.90%

Medium 4,755 4.60%

Light 35,545 34.40%

None 30,162 29.10%

TOTAL 103,478

Table2.Damagedistributionininspectedcommercialunits(VSG,2011)

DamageLevel NumberofBuildings FractionofTotal

Heavy/Collapse 2,440 16.40%

Medium 2,748 18.40%

Light 6,307 42.30%

None 3,409 22.90%

TOTAL 14,904


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(22.9%) were not damaged (Table2).

The total cost of this earthquake,including nancial losses andreconstruction efforts, is expectedto be US$ 500 million to 1 bil-lion. To help with the recovery,

over 2,250 permanent housesare expected to be completed by

August 2012. Additionally, founda-tions of 3,000 new housing unitswere laid with initial work startedon additional 12,000 housing units,all supported by the government.Distribution of these residences isexpected to start in August 2012.

Recommendations

Without doubt, Turkey has thestructural engineers, seismicdesign code, and constructionknow-how to avoid earthquakedisasters of this scale, but thedamage clearly demonstrated thatimprovement is needed in pre-earthquake mitigation. Almost allof the damage and deaths werecaused by the collapse of inad-equately designed and constructedbuildings, particularly buildings builtduring the last decade. Modern

buildings should have had lightdamage, given that the shakingintensities were moderate, butthey were not properly designedand/or not properly constructed.Obviously, an advanced buildingseismic design code does not guar-antee good performance of build-ings and their contents.

Design and construction. Thebuilding designs in seismic regionssuch as Van region should incor-

porate more and better distributedstructural walls. Building lateralload resisting structural systemsand the inll walls should bedesigned considering their possibleinteraction during earthquakes. Inthe current construction style theunreinforced inll walls are wedgedbetween and ush with the struc-tural elements. As a result, the inll

walls are engaged in the structuralresponse even though, at leaston paper, they are supposed tobe nonstructural elements. Whilethese inll walls may sustain littledamage at low-intensity shaking,during stronger shaking they aredamaged, typically in the form of

widespread cracking and evencrushing. Crushing of the inll wallscan cause development of cap-tive column condition which oftenresults in premature and brittlefailure of the affected columns.

Given the observed high frequencyof destructive earthquakes inTurkey, it would be worthwhile torevisit the code-specied drift ratiolimit considered for the design levelearthquake. It is possible that low-ering this drift limit would providelong-term benets that outweighthe short-term costs.

Several buildings inspected by theEERI team had improper designs.It could be that the code-enforce-ment bodies, which are the localmunicipalities in the case of privatebuildings, are unable to providecompetent reviews and/or enforcethe seismic design code. If it is the

latter, the state has to provide thenecessary checks and balances ofenforcement. However, if it is theformer, the technical skills of theengineers reviewing the designneed to be improved and a mini-mum level needs to be established.

A licensure process in engineeringshould be introduced to providea formal and objective means toassess the competency of designengineers. This would result inestablishment of engineering

cadres that could protect the safety,well-being and other interests of thegeneral public. Professional engi-neering certication ensures thatpracticing engineers meet require-ments for competency in theirspecic disciplines, and that engi-neering designs are reviewed andaccepted by qualied practicingengineers. Such a licensure pro-cess is being developed, but there

should be a higher level of licens-ing required for essential facilitiessuch as hospitals and schools.Those facilities should be designedonly by experienced professionalengineers specialized in structuraland earthquake engineering.Industrial losses also were avoid-

able. Many of the losses werecaused by equipment (tanks, ves-sels, etc.) not properly anchoredor braced to resist seismic loads.Such damage is well understoodby professionals and can be miti-gated at a modest cost.

Post-earthquake damage

assessment. Given the frequencyof large earthquakes affectingurban areas in Turkey, it behoovesthe Turkish government to orga-nize teams of experts that couldbe called to duty on short noticeto assist with the rapid inspectionof the buildings. Such teams couldbe supported by professional civilengineering associations. It is notreasonable to expect that localengineers, who are very likely tobe in crisis themselves, could bearthe burden of inspecting buildingsin their hometowns. Hospitals,emergency operations, and water

and power distribution networksneed continuity of operations afteran earthquake, so these facilitiesshould be surveyed and taggedright away. Instead, the inspec-tion process was quite slow andapparently resulted in much confu-sion. We visited several structureswhere the residents claimed thatsome people without ofcial ortechnical credentials inspectedtheir buildings, made statements,and gave ratings regarding the

damage state and soundness ofthe structure. No documentationwas left about those statementsand ratings.

A post-earthquake building tag-ging system should be developed,and engineers trained in rapidvisual screening methods shouldbe dispatched to the eld immedi-ately after the earthquake to inform


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building occupants whether it isnecessary to evacuate their build-ing or it is safe to go back inside.If the occupants of a damagedbuilding are evacuated, it is alsonecessary to decide if and whenemergency workers can enter thebuilding for search-and-rescue ortemporary shoring missions. Sucha system is already in place in theUSA, and has been used aftermany earthquakes with great suc-cess. Usually, the local governmentbody responsible for enforcing thebuilding safety code examinesthe affected structures and tagsthem as appropriate, but often theyreceive volunteer support from pro-fessional structural and earthquakeengineering associations.

Hazard mitigation. To develop aprogram for seismic risk mitiga-tion, the potential risks need to bequantied as accurately as pos-sible. Compared to other earth-quake vulnerabilities, buildingspose the largest risk to life, limb,property, and economic welfare.To determine vulnerable buildings,a countrywide building inventoryneeds to be prepared, starting fromthe heavily populated earthquake-

prone city centers. This inventoryshould be prepared based on rapidengineering assessments for everybuilding, so mitigation priorities canbe set. Afterwards, an earthquakemitigation plan for the entire coun-try should be prepared.

Acknowledgments

The EERI team members arethankful for the support providedby the EERI Learning from Earth-quakes program, zmir Instituteof Technology, and the George E.Brown, Jr. Network for EarthquakeEngineering Simulation OperationsCenter, NEEScomm. They arealso grateful for the logistical andtechnical support they receivedfrom the Earthquake EngineeringResearch Center of the Depart-ment of Civil Engineering at Middle

East Technical University (CenterDirector Prof. Sinan Akkar andDepartment Head Prof. GneyOzcebe), the Van Yznc Yl Uni-versity (Rector Prof. Peyami Battal),and the Turkish Gendarmerie Force(Lt. Gen. Yldrm Gven, Col.Rza Yaar, Cpt. Emre Gneri, Mr.Kemal Balyemez, and Mr. CenkSoysal). The EERI team mem-bers are thankful to Profs. Ayegl

Askan, dris Bedirhanolu, HalisBettemir, Bar Binici, Alp Caner,

Altu Erberik, Nuretdin Kaymak,Arda zaar, Afin Sarta, AhmetYakut, Tolga Ylmaz, Dr. Mehmetelebi (USGS), Dr. Hasan Korucu(Cpt., Turkish Naval Force), andgraduate students Vesile Hatun

Akansel, Alper Aldemir, zer Ay,

Ozan Demirel, Bar Erdil, zkanKale, Sercan Kran, ner Mete,Dilek Okuyucu, Ramazan zelik,and Cihat Yldrm for their help andgenerosity.

This report was edited by SarahNathe, EERI Newsletter InsertEditor.

References

British Broadcasting Corporation,

2011. Turkey earthquake: Survi-vors outdoors on freezing night.http://www.bbc.co.uk/news/world-europe-15437014

Cebeci, Uur, 2011 Hrriyet News-paper: http://www.hurriyet.com.tr/yazarlar/19229796.asp

Disaster and Emergency Man-agement Directorate (AFAD), 9November 2011 Earthquake Bulletin(in Turkish). http://www.deprem.gov.tr/sarbis/Shared/WebBelge.aspx?param=103 . Accessed 29November 2011

Disaster and Emergency Man-agement Directorate (AFAD),2011. Press Bulletin on the 23October and 9 November 2011Van earthquakes (in Turkish), 24November. http://www.deprem.

gov.tr/sarbis/Shared/WebBelge.aspx?param=103Doangn, et al., 2006. Tradi-tional Turkish Minarets on theBasis of Architectural and Engi-neering Concepts, Proceedingsof the 1st Int. Conf. on Restora-tion of Heritage Masonry Struc-tures, Cairo, Egypt, April 24-27

Eyidoan, H., 2011. Interview(in Turkish). http://www.t24.com.tr/vandaki-felaket-herke-sin-gozu-onunde-insa-edildi/haber/184080.aspx. Accessedon November 29

Gedikbulak Primary School,2011. http://okulweb.meb.gov.

tr/65/01/245329/contact.htm .Governors Ofce of Van Prov-ince, 2011. http://www.van.gov.tr/default_B0.aspx?content=1006 .

Glkan, P., Grpinar A., elebi,M., Arpat E., and Genolu S.(1978), Engineering Report onthe Muradiye-Caldiran, Turkey,Earthquake of 24 November1976. Published by the National

Academcy of Sciences, Wash-ington D.C., 59 pp

Hayes G., 2011. Finite FaultModel, updated result of theOct 23, 2011 Mw 7.1 easternTurkey earthquake, http://earth-quake.usgs.gov/earthquakes/eqinthenews/2011/usb0006bqc/nite_fault.php,

Middle East Technical Univer-sity Earthquake EngineeringResearch Center, 2011a. The23 October 2011 Mw 7.2 Van

earthquake seismic and struc-tural damage eld observations(in Turkish), Report # METU/EERC 2011-04, http://www.eerc.metu.edu.tr/sites/default/les/Van_ODTU_DMAM_Rapor.pdf

Middle East Technical Univer-sity Earthquake EngineeringResearch Center, 2011b. Pro-


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cessed Mainshock AccelerometricRecordings of the 23 October 2011Van Earthquake, Report # METU/EERC 2011-02, http://www.eerc.metu.edu.tr/sites/default/les/Report_Van_EQ_2011.pdf

Mineral Research and Explora-tion of Turkey (MTA), 1992. ActiveFault Map of Turkey, prepared byF. Saroglu, O. Emre, and I. Kuscu.http://www.mta.gov.tr/mta_web/dirifay1.asp

Ministry of Public Works and Settle-ment (MPWS), 1996. SeismicHazard Map, http://www.deprem.gov.tr/sarbis/shared/DepremHarital-ari.aspx

United States Geological Survey(USGS), 2011. Bulletin for the23 October 2011 magnitude 7.1eastern Turkey earthquake, http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/usb0006bqc.php

Uras, G., 2012. Article on economicimpacts of Van earthquake, http://ekonomi.milliyet.com.tr/8-290-vanli-cadirda-isi-gunduz-eksi-5-gece-eksi-14-derece/ekonomi/

ekonomiyazardetay/03.02.2012/1497350/default.htm,

Van Provincial Ofce of the StateReligious Affairs, 2011. http://www.vanilmuftulugu.gov.tr/cami_koy.htm

Van Sesi Gazetesi (VSG), 2011.Article on building damage inthe Van earthquake, http://vans-esigazetesi.com/haber_detay.asp?haberID=1193,

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