The February 27, 2010 Chile Earthquake

Roberto Leon School of Civil and Environmental Engineering Georgia Tech Atlanta, GA 30332-0355 Importance of this Event • 3rd largest earthquake in modern times – best proof of where our infrastructure is at. • Building codes in Chile are very similar to the USA (ACI, AISC, etc.) – what works and what does not? • Well-developed economy – direct and indirect losses can be translated to USA. • Design earthquake or above? • Human losses (about 450 deaths) and direct economic losses (up to $30B) – can this be translated to Seattle? A Brief Description of Chile

Area = 292,183 square miles Population = 17.0 million GDP (PPP) = $14,529 (43rd) Capital: Santiago (about 5.5 million) Main cities: Valparaiso (0.8 million) Concepcion ( 0.66 million)

• Strong economic2000 growth x 150 miles over the past 15 years – best in Latin America • Most important exports are minerals and agricultural products • Strong democracy following long military dictatorship • Excellent health and education infrastructure

Long, narrow territory = lack of alternate paths for all communications and services

ww.mapsofworld.com Pacific Rim of Fire

Vancouver Seattle Portland

4 SUBDUCTION PLATE INTERACTION

Marine Andes mountain West trench Coastline East range Pacific Ocean

Nazca Plate South American Plate

Intraplate (medium depth)

Intraplate (low depth - volcanic)

Interplate (Benioff Zone ) 1994 Bolivia Earthquake (Ms = 8.2; depth = 600 km

Redrawn after R. Saragoni ( U. of Chile) 5 SUBDUCTION ZONE 2.5 cm./year South American Name Ms 15.6 cm./year plate 1985 Santiago 8.0 Nazca plate 1995 Antofagasta 8.0 1906 Valparaíso 8.2 1943 Coquimbo 8.2 1922 Vallenar 8.5 5.9 cm./year 2010 Maule 8.8 1960 Valdivia 9.5

One major earthquake about every 15 years!

Redrawn after R. Saragoni ( U. of Chile) 6 Chile Coastal mountain range: • rugged deep valleys, • Concepcion is only large flat 2010 Maule

area near the coast, heavy (Ms = 8.8) industry concentrated there • no coastal highway, • forestry industry in the South, • important ports

Andes mountain range: 1960 Valdivia

• High , very cold (Ms = 9.5) • Mostly uninhabited • Skiing

Central valley: • Heavy agriculture (fruits and wine) • Main communication routes • Numerous small cities with older building stock (Rancagua, Talca, Chillon, Temuco)

http://www.mapsorama.com/maps/south-america/chile/Chile_topo.jpg February 27, 2010 Earthquake – Ms = 8.8 – Off Maule Coast

R. Saragoni ( U. of Chile)

Length of rupture = 400 to 450 km Accelerograms – Santiago

Epicenter: 335 km (210 miles) SW of SANTIAGO, Chile

Soto &Boroscheck – U. of Chile - wwww.terremotosuchile.cl Spectrum from Santiago

Soto &Boroscheck – U. of Chile - wwww.terremotosuchile.cl A trip though Chile

• Viña del Mar/ Valparaiso • Constitucion • Santiago • Talcahuano • Concepcion • Coronel

Lots of damage pictures to come but performance of most structures was excellent Viña del Mar Older RC Buildings

USA buildings = 1.0% to 1.5% walls

Chilean buildings = 5 to 6% walls

Wallace, J. & Moehle, J., ASCE JSE 118(4), 1992

Festival building had survived the 1985 earthquake with some damage Older RC Buildings

Wallace, J. & Moehle, J., ASCE JSE 118(4), 1992

Stairs linking both buildings heavily damaged Wallace, J. & Moehle, J., ASCE JSE 118(4), 1992 Damage to modern RC buildings Crushed shear walls at transition zones Poorly detailed boundary elements for shear walls Poorly detailed boundary elements for shear walls

USA wall with boundary elements

Is this repairable? Chilean wall without boundary elements Other examples of modern damaged RC buildings Non-Structural Damage to Walls Non-Structural Damage to Equipment How many and how badly damaged? Santiago

Building 1 Plaza Mayor Radisson Ciudad Empresarial Plaza Mayor Ciudad Empresarial Plaza Mayor Ciudad Empresarial Plaza Mayor Ciudad Empresarial Radisson Hotel Ciudad Empresarial Damage to Condominiums Parque Hipico

• Shear failures in walls • Large cracks and crushing in slabs near connections to walls • Failure of very slender columns Plaza Mayor Ciudad Empresarial Santiago

Ciudad Empresarial & Vespucio Norte Vespucio Norte Tollway – Santiago’s Ring Road

Typical interchange Presstresed Girders Bridges

Poor lateral support of girders at skew abutments Vespucio Norte - Collapsed Spans

Insufficoent bearing length to accommodate longitudinal movement Vespucio Norte - Collapsed Spans

Poor detailing of longitudinal and transverse restraints Vespucio Norte - Collapsed Spans

Continuous, heavily reinforced slabs over the interior supports Plaza Norte Shopping Center

Local anchorage failures leading to partial collapse of roof and floor slabs, and large out-of-plane movements in precast wall panels Large Warehouse

Failure of precast exterior panels due to improper anchorage (damaged portions being replaced by light steel cladding). Storage racks performed very well even if they had only minimal anchorage A trip though Chile

• Viña del Mar/ Valparaiso • Constitucion • Santiago • Talcahuano • Concepcion • Coronel Rute 5 – Main North-South Tollway

Evidence of large settlements in backfill areas Damaged bridges – Ruta 5 – Rancagua Area Damaged bridges – Ruta 5 – Granero Area Damaged bridges – Ruta 5 – Granero Area Older bridge between San Antonio and Santo Domingo

Note large horizontal displacements Older bridge between San Antonio and Santo Domingo

Note large horizontal, rigid body displacement Older Adobe Buildings – La Fortuna Winery Caskets on ground – La Fortuna Winery Buckled tanks – La Fortuna Winery Overturned tanks – La Fortuna Winery Bio-Bio Cement Plant

Buckled braces near the top Fine shear cracks in large storage silos of bagging facility Constitucion - Chile

Arauco pulp factory Tsunami Downtown Constitucion – Largest City near Epicenter Constitucion – Largest City near Epicenter Constitucion – Largest City near Epicenter Constitucion – Largest City near Epicenter Constitucion – Tsumani area Constitucion – Tsunami Area Constitucion – Tsunami Area Constitucion – Tsunami Area Arauco Brown Paper Plant A trip though Chile • Viña del Mar/ Valparaiso • Constitucion • Santiago • Talcahuano • Concepcion • Coronel Tahualcano – Tsunami Area Tahualcano – Tsunami Area Tahualcano – Tsunami Area Tahualcano – Tsunami Area Concepcion – Collapsed Buildings Concepcion – Collapsed Buildings Concepcion – Collapsed Buildings Concepcion – Collapsed Buildings Industrial Facilities

Santa Maria Power Plant (Coronel (50% complete) Industrial Facilities

Santa Maria Power Plant

Generator Building

Potential damage to generator as it was in the final stages of being aligned when the earthquake struck Industrial Facilities

Santa Maria Power Plant

Coal Storage Facility Distribution cart damaged Industrial Facilities Santa Maria Power Plant

Coal Storage Facility Distribution cart damaged Port of Coronel

New base-isolated wharf and cranes undamaged

Some evidence of ground movements in storage areas

Damaged steel trusses in warehouses – probably due to collisions and not earthquake Port of San Vicente – Tsunami Damage

Damage to old canning plant from tsunami dragging unloading pipes; towers connected to pipes were tipped over; evidence of large settlements Summary

• Much of the infrastructure did very well but importance of using codes in their entirety was highlighted • Vulnerabilities of some privately-controlled infrastructure (tollways, communications, etc.) was evident • Emergency response could have been better: tsunami evacuation, use of the military,.. • Human losses (about 450 deaths) and direct economic losses (up to $30B) • Recovery efforts: $750M for first phase and $700M in second phase