ASSESSMENT OF DAMAGE AND ASSESSMENT OF DAMAGE AND USABILITY OF EARTHQUAKE-USABILITY OF EARTHQUAKE-

DAMAGED BUILDINGS: DAMAGED BUILDINGS: EXPERIENCE OF SLOVENIAEXPERIENCE OF SLOVENIA

Miha TomaževičMiha Tomaževič

Slovenian National Building and Civil Engineering InstituteSlovenian National Building and Civil Engineering Institute

MiMilica Slokarlica SlokarAdministration of Civil Protection and Disaster Relief of the Republic of Administration of Civil Protection and Disaster Relief of the Republic of

SloveniaSlovenia

SSeismic riskeismic risk in in SSlovenialovenia

• 1/3 of the population of Slovenia is concentrated in regions where earthquakes with PGA = 0,2 g and more are expected with return period of 475 years.• In Ljubljana region, the most densely populated area of the country, where the basic functions of the country are concentrated, seismic hazard is even more severe.• Most of the damage and casualties are due to inadequate seismic behaviour of existing buildings. The existing building stock (mainly unreinforced masonry buildings) is estimated to be almost 50% of the total.

Rural Rural architecturearchitecture

CastlesCastlesUrban Urban

architecturearchitecture

Typical heritage masonry buildings in SloveniaTypical heritage masonry buildings in Slovenia

Pre-World War II Pre-World War II buildingsbuildings

Pre-1963 unreinforced Pre-1963 unreinforced masonry tower houesmasonry tower houes

Typical pre-seismic codes masonry residential Typical pre-seismic codes masonry residential buildings in Ljubljanabuildings in Ljubljana

History of seismic codesHistory of seismic codes1895: the earthquake of Ljubljana1931-33: the skyscraper of Ljubljana - base isolation1963: seismic design recommendations1964: first Yugoslav seismic code1981: revised Yugoslav seismic code1995: Eurocode 8, ENV version translated as alternative2008: Eurocode 8 mandatory

Existing buildingsExisting buildings1978: law on seismological service1985: Yugoslav code for repair and strengthening of earthquake-damaged buildings2008: Eurocode 8-3 Assessment and strengthening of buildings mandatory

Experience in earthquake-damage Experience in earthquake-damage assessmentassessment

• 1974: Kozjansko Region Governmental committee for damage evaluation. 4 categories of damage

• 1976: Friuli earthquakes. Posočje Region Governmental committee for damage evaluation. 3 categories of damage, 3 categories of usability

• 1998: Upper Posočje Region ACPDR. 5 categories of damage, 3 categories of usability. Categories of damage compatible with definitions given in EMS scale

• 2004: Upper Posočje Region

Assessment of usability and damageAssessment of usability and damage

• Rapid evaluation: To assess usability of buildings and provide information regarding the safety of occupancy and assess the number of inhabitants needing temporary shelters

• Detailed evaluation: To provide detailed information regarding the damage to buildings, which can be used as a basis for the assessment of damage costs

Pages 2 and 3 of questionnaire for usability and damage assessment

GIS-UJME Applications GIS-UJME Applications AAddress search, number of inhabitants ddress search, number of inhabitants

calculationcalculation

Classification of damage Classification of damage to masonry buildings as to masonry buildings as

defined by EMS scaledefined by EMS scale

• DDamage category 1: negligible to amage category 1: negligible to slight damageslight damage• DDamage amage category 2: moderate category 2: moderate damagedamage• DDamage category 3: substantialamage category 3: substantial to heavy to heavy damagedamage• DDamage category 4: very heavyamage category 4: very heavy damage damage• DDamage category 5: partial or amage category 5: partial or totaltotal collapse collapse

Classification of usabilityClassification of usability

• Usable buildingsUsable buildings• Temporarily not usable buildingsTemporarily not usable buildings• Unusable buildingsUnusable buildings

Classification of usabilityClassification of usability

Usable buildingsUsable buildings markedmarked greengreen

Restriction: Restriction: BBuilding occupancy may continue uilding occupancy may continue

without limitationwithout limitation

DDamage category 1 and 2 amage category 1 and 2 ::Undamaged buildings Undamaged buildings

Slight structural damageSlight structural damageModerate non-structural damageModerate non-structural damage

Classification of usabilityClassification of usability

Temporarily not uTemporarily not usable buildingssable buildings markedmarked yellowyellow

Restriction: Restriction: OOccupancy may continue if the safety can ccupancy may continue if the safety can

be ensured by emergency safety be ensured by emergency safety measures. In most cases, the occupancy measures. In most cases, the occupancy

is not possible until the building is is not possible until the building is completely repaired and strengthenedcompletely repaired and strengthened

DDamage category amage category 33::Substantial damage to structural systemSubstantial damage to structural system

Heavy non-structural damageHeavy non-structural damage

Classification of usabilityClassification of usability

UnuUnusable buildingssable buildings markedmarked redred

Restriction: Restriction: Unusable, unsafe buildings are Unusable, unsafe buildings are

demolished and the debris removeddemolished and the debris removed

DDamage category amage category 4 and 54 and 5::Heavy structural damage, very heavy non-Heavy structural damage, very heavy non-

structural damagestructural damageTotal or near total collapseTotal or near total collapse

Assessment procedureAssessment procedure

UsabilityUsability AAssessment Commission is ssessment Commission is usually usually composedcomposed of of 2 2 expertsexperts and local guide, and local guide, who who

assess 20 –30 buildings per dayassess 20 –30 buildings per day (rapid (rapid assessment)assessment)..

For easier identification of buildings, special For easier identification of buildings, special municipality mmunicipality maps aps inin seismic seismic-prone -prone areas areas ofof

Slovenia Slovenia have been prepared by ACPDR. have been prepared by ACPDR. MMunicipalitunicipalities are ies are divided into several zonesdivided into several zones, ,

each including each including appapproximatelyroximately 100 100buildings. Each zone buildings. Each zone isis limited by natural limited by naturalor physical objects (streets, rivers, etc.)or physical objects (streets, rivers, etc.)..

Civil Protection Headquarter of RS

Regional Civil Protection Headquarter

Local Civil Protection Headquarter

Damage assessment Commission

The case of the earthquake of The case of the earthquake of Bovec of April 12, 1998Bovec of April 12, 1998

• BBased on ased on the the information received from local staff of Civil information received from local staff of Civil Defence, ACPDR immediately mobilised 25 professionals,Defence, ACPDR immediately mobilised 25 professionals, who inspected the damaged buildings and assessed their who inspected the damaged buildings and assessed their usability according to the proposed methodologyusability according to the proposed methodology• OOnly buildings with permanent residents and some culturalnly buildings with permanent residents and some cultural monuments have been included in the rapid evaluation of monuments have been included in the rapid evaluation of damage and usabilitydamage and usability. . Four days have been needed to Four days have been needed to complete rapid evaluation. complete rapid evaluation. 952 buildings have been952 buildings have been inspected. inspected.• 311 311 buildings buildings have been found as temporarily not usable. have been found as temporarily not usable. Among them, 1/3 have been Among them, 1/3 have been seriously seriously damageddamaged,, in some in some cases even beyond repair, and 2/3 have suffered repairablecases even beyond repair, and 2/3 have suffered repairable damagedamage. . More than 710 people have been temporarilyMore than 710 people have been temporarily movedmoved to mobile homes, located close to their homesto mobile homes, located close to their homes.

Experience after the Experience after the earthquake of 1998earthquake of 1998

• TTimely and constant training of professionals, who will beimely and constant training of professionals, who will be mobilised in the case of an earthquake disaster, for both mobilised in the case of an earthquake disaster, for both usability assessment and damage evaluation, is needed usability assessment and damage evaluation, is needed. . Otherwise, significant delays inOtherwise, significant delays in earthquake disasterearthquake disaster mitigation activities can be expected mitigation activities can be expected• Therefore, Therefore, within the earthquake preparedness program of within the earthquake preparedness program of Slovenia, prepared by ACPDR, a continSlovenia, prepared by ACPDR, a continuuoouus training of s training of experts, members of committees for the assessment ofexperts, members of committees for the assessment of damage and usability of earthquake damage buildings has damage and usability of earthquake damage buildings has been set forth been set forth

Experience after the Experience after the earthquake of 1998earthquake of 1998

• FFirst exercise has been irst exercise has been organized organized during a during a simulationsimulation of an earthquake disaster, carried out in Ljubljana of an earthquake disaster, carried out in Ljubljana in 1999 in 1999• In 2001, the In 2001, the members of committees for the members of committees for the assessment of damage and usability of earthquakeassessment of damage and usability of earthquake damage buildings damage buildings have been have been educated educated duringduring courses organized in the ACPDR’s the training courses organized in the ACPDR’s the training centre. In the years to follow, the knowledge has centre. In the years to follow, the knowledge has been improved by practical exercises on been improved by practical exercises on earthquake-earthquake- damaged buildings damaged buildings on the site on the site• About 200 professionals have been trained so farAbout 200 professionals have been trained so far

THANK YOU!THANK YOU!