July 1, 2010
Building Research Institute, Japan

Preliminary Reconnaissance Report of the Chile Earthquake 2010
Hiroto Kato, Seitaro Tajiri**
Department of Structural Engineering, Building Research Institute, Japan
andTomohisa Mukai
International Institute of Seismology and Earthquake Engineering, ditto

Preface
A great earthquake of magnitude 8.8 struck on the Pacific coast of Chile, at 3:34a.m. local time on February
27, 2010, and the earthquake and Tsunami caused widespread damage in Chile.
After the earthquake, Ministry of Housing and Urbanism of Chile appealed Japan to dispatch experts who
have superior technology and experience on inspection of damaged buildings. Japanese government
decided to dispatch experts through JICA #1 on the request of them. Three researchers of Building ResearchInstitute took part in the expert team (JICA expert team) and conducted disaster investigation especially forbuildings from March 13 to 23, 2010.

Table of Contents
1. Earthquake data and summary of damage･･････････････････････････

2

2. Damages in affected areas･･････････････････････････

3

3. Features of damaged buildings･･････････････････････････ 30

Acknowledgement･･････････････････････････ 39

References･･････････････････････････ 39#1Name of investigation team: Expert team for inspection of damaged buildings in Chile
earthquake, 2010
Principal purpose of the investigation team are as follows:
1) Conduct and support on damaged building inspection technically with jointly establishedteam from Universidad Católica de Chile (Católica University) and Universidad de Chile(University of Chile) requested by Servicio de vivienda y urbanismo (Housing Service and
Urbanism of Chile).
2) Confirm assignments of damaged building inspection, decreasing the earthquake damage
and further needs through the investigation.

**

Belong to Government Building Department of Ministry of Land, Infrastructure, Transport andTourism from April, 2010-1-

1. Earthquake data and summary of damage
Earthquake details reported by US Geological Survey (USGS) [1] are as follows:
Date: February 27, 2010 at 06:34:14 UTC, 03:34:14 local time
Earthquake Center: 35.9°S, 72.7°W, 35 km (21.7 miles) depth
95 km (60 miles) NW of Chillan
115 km (70 miles) WSW of Talca
105 km (65 miles) NNE of Concepcion
335 km (210 miles) SW of Santiago
Magnitude: Mw8.8
It was approximate five hundred thousand (500,000) people living within 100-kilometer radius and three
million (3,000,000) people within 200-kilometer radius from the earthquake source and the strong seismic
vibration affected and caused extensive damage to wide area in particular following four states: Libertado,
Maule, Biobio and Metropolitana (Santiago).
Summary of damage caused by the earthquake based on OCHA and USAID report is as follows:
Dead: 432 people (by Chile government as of March 27)
Missing: 98 people (OCHA) [2]
Victims: More than 1.8 million (by OCHA as of March 29) [2]Damaged houses : Approx. 810,000 houses (More than 160,000 houses were seriously damaged orcollapsed, More than 93,000 houses are need damage inspection) [2]
The total amount of damage: Approx. US$30 billion
Abbreviated expressions used in this report:
USGS
U.S. Geological Survey
OCHA
USAID
MINVU
SERVIU #2
IDIEM
DICTUC#2

United Nations Office for the Coordination of Humanitarian Affairs
United States Agency for International Development
Ministerio de Vivienda y Urbanismo (Ministry of Housing and Urbanism)
Servicio de vivienda y urbanismo (Housing Service and Urbanism)
Instituto de Investigación Ensayos de Materiales, Universidad de Chile(Institute of Investigation Specification tests, University of Chile)
Dirección de Investigaciones Científicas y Tecnológicas de la Pontificia Universidad
Católica de Chile (Direction of Scientific and Technological Investigations of the Papal
Catholic University of Chile)

SERVIU constructs large number of apartment houses for low-income group in Chile. JICA expert
team could not obtain the detailed information of the damage, i.e. number of buildings and damage
degree. According to the hearing from Chief of SERVIU Biobio state, initial evaluation of 26,000
buildings under the jurisdiction of SERVIU had completed and of those 7,000 buildings were still
conducted detailed investigation. So far, they estimated approximate 1,800 buildings would be
demolished. After the earthquake, SERVIU and local government officials conducted initial damage
inspection of buildings and ordered inhabitants to vacate from dangerous housings. Detailed
damage inspection has been conducting by DICTUC and IDIEM, around 30-40 experts who were
professors of universities, structural engineers and students were engaged in the inspection works.
They contracted for the inspection from private sectors other than SERVIU. At the stage of hearingon March 19, they completed the inspection of 50 buildings of SERVIU, 50 high-rise buildings and
200 houses.
In Chile, they have not prepared the normalized method for damage inspection of buildings and theblank form. Some institutes used an inspection method that was imported from Colombia andrevised, and others used their own way. JICA expert team advised technically on the damage
inspection of buildings, regarding the apartment houses for low-income group by request of
MINVU.

-2-

2. Damages in affected areas
Investigated locations by JICA expert team are shown in Figure 1 with editing the map created by OCHA.
Investigated locations are eight cities: Santiago, Constitucion, Talca, Cauquenes, Pelluhue, Dichato, Penco,and Concepcion. In addition, Chillan is just for reference.

Santiago

Constitucion

Talca

Pelluhue
DichatoCauquenes
Penco

Concepcion

ChillanFigure 1 Investigated locations by JICA expert team (edit the map created by OCHA)-3-

2.1 Santiago
Damaged building inspections shown in Figure 2 were conducted in Santiago. They are relatively new
private buildings (condominiums) and apartment houses constructed by SERVIU.
No.6 Edificio Raddison
No.7 Edificio Paito

Arturo Merino Benítez International
Airport (Santiago International Airport)

No.11 Japanese school

No.12 Villa Portales
No.8 Edificio Don Tristan housing complex
No. 9 Edificio Don Luis
No.1 Edificio
No. 10 Edificio Los Jazmines
Los Leones

No.2 Edificio Sol
Oriente No.4 Edificio Los
No.3 Edificio
Emerald

Cerezos

No.5 Edificio Parque
Residencial
Figure 2 Investigated buildings in Santiago (tack building number on the google map)

No.1 Edificio Los Leones
A condominium was completed in 2009 and has 12 floors (2 basements) with reinforced concrete (RC) wallconstruction (Photo 1-1). The basements are parking garage and span direction wall of the first basement
was smashed up as Photo 1-2, and axially compressed. Wall thickness was 150mm.

-4-Photo1-1 Appearance

Photo1-2 Smashed RC wall

No.2 Edificio Sol Oriente
A condominium has 18 floors (2 basements) with RC wall construction. A similar building is in front of
Photo 2-1 and the basements for parking garage are between two buildings. Most of RC walls in span
direction were smashed at the upper part of walls on the first level basement (Photo 2-2 and Photo2-3).
Axial reinforcement is D25 and hoop is D8 #3. Extensive damage happened on a part of capitals andstreamed through the slab at the first floor (Photo 2-4).

Photo 2-1 Appearance

Photo 2-2 Smashed RC wall

Photo 2-3 Close-up of wall column

Photo 2-4 Damaged RC column

No.3 Edificio Emerald
This is a high-rise condominium with slender form and has 20 floors. Although it was informed that thewhole building was slightly sloped, internal building could not be investigated without permission. Thisbuilding was already determined uninhabitable by the municipal authorities (Photo 3-1 and Photo 3-2).

#3This notation does not mean the deformed reinforcement established by Japanese Industrial
Standard, but used considerable diameter as deformed reinforcement. The similar manner will beapplied in following descriptions.

-5-Photo 3-1 Appearance

Photo 3-2 Determination by the municipal
authorities

No.4 Edificio Los Cerezos
Photo 4-1 is a high-rise condominium of RC wall construction with 26 floors (1 basement). The bottom of
RC wall column next to the entrance was crushed as shown in Photo 4-2 (axial rebar is D35 and hoop isD13). Photo 4-3 shows the internal view of the column. Additionally, the beam-column joint of relevant
wall at the first level basement was severely damaged (Photo 4-4). This possible causes are multistory shear
wall is lost at the underground.

Photo 4-1 Appearance

Photo 4-3 Internal view of Photo 4-2

Photo 4-2 Crushed column bottom

Photo 4-4 Underground portion of Photo 4-2

No.5 Edificio Parque Residencial
Photo 5-1 shows a high-rise condominium with RC construction and the number of floors is 22 with 38
years after construction. The exterior of nonstructural brick walls were cracked almost all floors as shownin Photo 5-2. Notable damages could not be seen in structural members.

-6-

Photo 5-1 Appearance

Photo 5-2 Damaged outer wall with bricks

No.6 Edificio Raddison
This is an accommodation with 12 floors and only appearance was investigated since access to this building
was prohibited (Photo 6-1). The beam-ends of low-rise building, the joint part with high-rise building, andthe joint parts of column capital were damaged (Photo 6-2). According to an investigator of this internalbuilding, some crush occurred on RC angle posts at the basement.

Photo 6-1 Appearance

Photo 6-2 Damaged wall beam

No.7 Edificio Paito
This building group is a commercial establishment with five floors and with other four (Photo7-1). The
blindfold wall of external staircase was crumbled. The short spanned wall beams because of nonstructuralwall were severely damaged and a part of beam-column joint were broken (Photo 7-2). The penthouse wasinclined because of the slab just below was crumbled (Photo 7-3). Earthquake induced ground deformation
could be seen on its property (Photo 7-4).

Photo 7-1 Appearance (crumbled external staircase)-7-

Photo 7-2 Damage on beam and beam-column joint

Photo 7-3 Crumbled penthouse

Photo 7-4 Ground deformation

No.8 Edificio Don Tristan
Photo 8-1 is the situation of a five-story building with RC construction for residence. The site is sloped
along span direction of building (right side in Photo 8-2). The wall columns in longitudinal direction werein destruction and story collapse was confirmed at first story.

Photo 8-1 Appearance (longitudinal direction)

Photo 8-2 Appearance (span direction)

No.9 Edificio Don Luis
The building is a condominium of RC construction with five floors and soft first story (Piloti). Number ofbearing wall is lacking at the first story; parking garage (Photo 9-2). Hinges occurred on capital and bottomof wall columns because of tensile axial force and bending, further story collapse was confirmed at the firststory (Photo 9-3). The bearing walls without lateral columns showed shear failure (Photo 9-4).

-8-

Photo 9-1 Appearance

Photo 9-2 First floor parking garage (Piloti)

Photo 9-3 Wall column with bended hinge

Photo 9-4 Shear failure

No.10 Edificio Los Jazmines
This building is a condominium of RC construction with soft first story (Piloti) and has four floors (Photo
10-1). Outer parts of building at the first floor are composed of T-shaped wall columns and multistory shear
walls construct center part. T-shaped wall columns were severely damaged around 500-600mm high as
Photo 10-2 shown and concrete of them were fallen off and could not bear the axial force. Concrete ofbearing walls at the first story dropped and damage was severe. Fillers like polystyrenes were found at the
top of wall at left side of the entrance, therefore it is estimated that the bearing wall at periphery does notwork effectively against earthquake force.

Photo 10-1 Appearance-9-

Photo 10-2 Damaged T-shaped wall columns and bearing walls

Photo 10-3 Fillers like polystyrenes
No.11 Japanese school
The building in Photo 11-1 is the auditorium of Japanese school in Chile and has two floors with concrete
block construction. Minimal crack was observed in joint part of block walls and cantilever walls which
thrown out from the building frame (Photo 11-2). Small gap was found in a part of ceiling panel, but they
were small damage as a whole (Photo 11-3).

Photo 11-1 Appearance

Photo 11-2 Crack of cantilever walls

Photo 11-3 Ceiling gap- 10 -

No.12 Villa Portales housing complex (BLOCK-4)
An apartment house for low-income group constructed by SERVIU, it has four floors with double-loaded
corridor and 54 years after completed (Photo 12-1). The structure is moment resisting frame with RCbearing walls and nonstructural brick walls (Infilled Wall structure #4).
SERVIU requested IDIEM for damage investigation and already completed. A document posted at theentrance shows the inspection results and precaution statement (Photo 12-2). Cracks were appeared onmasonry walls in double-loaded corridor and party wall, and some parts were completely fallen off(Photo12-3). This building was kept using through earthquakes happened in Chile in 1960 (Mw9.5) and in1985 (Mw7.8). Renovation of cracks was found on masonry walls. Meanwhile, some cracks occurred onbeam elements, which support the external staircase landing, and vertical deformation with long-termloadings on them were observed (Photo12-4). In other building, a roller supported beam at roof was fallen
off because of the earthquake (Photo 12-5), and should be taken measures as a part of reinforcement work.
Minister of Housing and Urbanism of Chile visited the building in time with the investigation of JICA
expert team and held a press conference, since she assumed the post. Japanese ambassador to Chile, Mr.
Wataru Hayashi and JICA expert team also joined it and televisions and newspapers reported those #5.

Photo 12-1 Appearance#4

Photo 12-2 Inspection results

These structures are sometimes indicated as Infilled Wall structure to distinguish in particular.
The details will be shown in Chapter 3.

#5Visit at the site and press conference with Minister of Housing and Urbanism of Chile, Ms.
Magdalena Matte Lecaros- 11 -

Photo 12-3 Damages of masonry walls

Photo 12-4 Cracks and deflection of beam at external staircase landing

Photo 12-5 Fallen beam from roof
No.13 Others
In most cases, old masonry buildings (stone masonry or brick construction) in the investigated areas ofSantiago did not show damages. Some minor problems as door was not opened might happen in many
ordinary buildings however, apparent damages were not seen #6. Adobe structure buildings did not exist
anymore in Santiago. Furthermore, it is explained that construction of Adobe structure buildings will not beallowed in the future even if in local areas.

Photo 13-1 Masonry structure buildings in Santiago (No damage)- 12 -

Photo 13-2 General buildings in Santiago (No damage)

2.2 Constitucion, Región del Maule
Constitucion is a seafront small city with a population of 38,000 and located at the mouth of Maule River,where flat land is few and mountains are behind. JICA expert team investigated apartment houses of
SERVIU and the city, and Tsunami disaster near the seashore was inspected at the points shown in Figure 3.
The outline of Tsunami disasters will be described in Chapter 2.9.
Trace of Tsunami disasterNo.1 Apartment houses
on hillside

River mouthNo.2 Apartment houses
near river mouth

Figure 3 Investigated buildings in Constitucion (tack building number on the google map)

#6

According to the announced strong motion observation record [3], the acceleration of surface inSantiago was 0.2g-0.3g except a few points and it is imagined the scale was intensity 5+ to 6- inJapan Meteorological Agency Seismic Intensity Scale.

- 13 -

No.1 Apartment houses on hillside
Apartment houses of Confined Masonry (CM) structure with three floors exist on hillside, which wereconstructed by SERVIU around 10-15 years ago for low-income group (Photo 14-1). Dimensions ofcolumns are 200x300mm. Axial reinforcement is D10 and hoop is φ4 with about 150mm spacing. Hollow
bricks composed walls and horizontal rebar at masonry joint reinforced the wall every 4-5 layer of bricks,
but no vertical reinforcing bars (Photo14-2).
Story collapse at the first story was confirmed in a building built in the highest place near the cliff (Photo14-3), and two families with eight people were dead. Cracks appeared on the upper of the cliff and it might
be banking structure. There was no hoop in beam-column joint (Photo 14-4).

Photo 14-1 Appearance

Photo 14-2 Columns and walls with CM structure

Photo 14-3 Buildings with story collapse at first story- 14 -

Photo 14-4 Beam-column joint
No.2 Apartment houses near river mouth
Apartment houses constructed by SERVIU are near the river mouth. The buildings were CM structure withbricks and have four floors after 20 years construction (Photo 15-1). Tsunami marked a trace at about
400mm high of floor.
Shear failures of transverse wall were found, and the floor height was down in a building out of four (Photo15-2). There were rock pockets and rusted reinforcing bars in the broken part. Beam of top of transverse
wall came down in another building (Photo 15-3 and Photo 15-4).

Photo 15-1 Appearance

Photo 15-2 Shear failure of transverse wall

- 15 -

Photo 15-3 Damaged beam for top of transverse wall

Photo 15-4 Fallen beam

No.3 Damages of old brick construction and Adobe structure
Buildings with old brick construction and Adobe structure were damaged in many places in Constitucion,
while the damage of new low-rise houses built on mountainside were slight.

Photo 16-1 Damages of old brick structure and Adobe structure

2.3 Cauquenes, Región del Maule
Damage inspections for apartment houses of SERVIU were conducted in Cauquenes. Location of
investigated buildings is shown in Figure 4.

No.1 Apartment houses

Figure 4 Investigated buildings in Cauquenes (tack building number on the google map)

- 16 -

No.1 Apartment houses
There are four apartment houses of SERVIU with CM structure and three floors constructed 16 years ago
on a gentle hillside. Hollow bricks composed the walls, and horizontal reinforcements were arranged inmasonry joint every 4-5 layer in longitudinal direction, but nothing in span direction. Walls at the first story
suffered from shear failure at the highest building, and almost all columns were severely damaged andsmashed (Photo 17-1). Shear cracks were found in one building out of two which separated by Expansion
Joint (EXP.J, almost no space), but not so big damage (Photo 17-2).

Photo17-1 Damaged transverse wall and longitudinal direction wall

Photo 17-2 Shear cracks of longitudinal direction wall (Another building)

2.4 Talca, Región del Maule
Talca is a medium-size city with a population of 200,000 and located about 115km away from theearthquake source. Here we investigated the damage of apartment houses with CM structure, SERVIU
office building and construction site of low-rise houses with CM structure. Figure 5 indicates the points ofinvestigated buildings.

- 17 -

No.4 Public housing

No.3 SERVIU officebuilding
No.2 High-rise officebuilding

No.1 Construction site of
low-rise houses
Figure 5 Investigated buildings in Talca (tack building number on the google map)
No.1 Construction site of low-rise houses
Photo 18-1 shows construction work of low-rise houses with two-story of which the first floor is CM
structure and the second floor is wooden structure. Vertical reinforcements of columns, and those of walls(500mm spacing) were arranged on concrete foundation, and hollow bricks were subsequently stacked as
walls. The walls contain horizontal reinforcing steels, and the top of walls and columns were unified bycast-in-place concrete beam. Main reinforcements in column and footing beam were straightly anchored in
the joint, and corner bars of 90-degree bend with 400mm (40d) length were arranged on main
reinforcement (Photo 18-2). The spacing of hoops in column was around 200mm, but the angle of hook end
was not 135-degree. The slab was one-way joist slab using concrete blocks (Photo 18-3). Masonry walls
were collapsed to out-of-plane direction before concrete was casted in columns (Photo 18-4).

Photo 18-1 CM structure house underconstruction

Photo 18-2 Bar arrangement of footing
beam and corner- 18 -

Photo 18-3 Joist slab

Photo 18-4 Fallen Masonry walls

No.2 High-rise office building
Nonstructural elements of an office building with RC structure were fallen off (Photo 19-1). Granularfoamed polystyrene were contained in concrete materials (Photo 19-2).

Photo 19-1 Appearance

Photo 19-2 Foamed polystyrene containedin concrete

No.3 SERVIU office building
A SERVIU office building of RC structure in Talca with 30 years after construction had six floors (top threefloors are apartment), and steel columns composed the outer frames in longitudinal direction (Photo 20-1).
Broken windows were scattered on outdoor passage (Photo 20-2). Shear failure of masonry walls at thefront, RC bearing walls, and most short span beams of top of the door were observed (Photo 20-3). Fouraxial reinforcements were arranged in wall edge, but the spacing of reinforcement was narrow (Photo20-4).

Photo 20-1 Appearance

Photo 20-2 Longitudinal direction outerand broken windows- 19 -

Photo 20-3 Shear failure of bearing walls and short span beam

Photo 20-4 Bar arrangement in wall edge
No.4 Public housing
This is a public housing for low-income group with 50 years after construction, and the dimension is longside 47.4m x short side 7.7m and five floors with RC construction (Infilled Wall structure, Photo 21-1).
Back of the front wall in Photo 21-2 is an adjacent house, and those were built with EXP.J without any
space, so masonry structure walls were damaged because of shock and vibration of the earthquake andalmost fallen from the RC structure. Other than above, damages of nonstructural brick walls, and exposureof reinforcing bars of transverse wall edges were found (Photo 21-3). Damages seem moderate, but
SERVIU officials told this housing would be demolished.

Photo 21-1 Appearance- 20 -

Photo 21-2 Damaged masonry wall

Photo 21-3 Damaged corner columns

No.5 Others
Old brick constructions and Adobe structures everywhere in the city were severely damaged (Photo 22-1).
Comparatively new buildings and houses did not receive so much damage (Photo 22-2).

Photo 22-1 Damages of brick and adobe structures

Photo 22-2 Comparatively new buildings and houses

2.5 Concepcion, Región del Biobío
Concepcion is a city with a population of 220,000 and located about 105km away from the earthquake
source. Here we investigated the damage of new-built office buildings and fallen condominium. Locationsof investigated buildings are shown in Figure 6.

- 21 -

No.2 Office building

No.3 Alto Rio

No.1 Torre O’Higgins
Figure 6 Investigated buildings in Concepcion (tack building number on the google map)
No.1 Torre O’Higgins
A high-rise office building of 21 floors with RC structure constructed in 2008 was in urban area (Photo
23-1). Story collapse occurred in the middle story near the 12th floor at the front of the building (Photo23-2). Upper stories were inclined to roadside, and the front street was impassable. Setback was found near
the story-collapsed floor. There were multistory bearing walls in backside of the building, and noremarkable damage. According to SERVIU officials, the owner will plan to demolish only the upper storiesof the story-collapsed and continue to use the building.

Photo 23-1 Appearance- 22 -

Photo 23-2 Story collapse near 12th floor
No.2 Office buildingThis is an office building constructed by SERVIU and has four floors with RC structure (Photo 24-1).
Masonry walls of inside and stairway were smashed (Photo 24-2) and documents were scattered.
Bending-shear cracks occurred at regular interval on the capital of circular RC columns of 3rd and 4th floor(Photo 24-3). Nonstructural walls had severe damages, but the building will be able to use after adequate
restoration.

Photo 24-1 Appearance

Photo 24-2 Damage of masonry e wall

Photo 24-3 Bending-shear cracks of circularcolumnNo.3 Alto Rio
This condominium was built in 2008, had 15 floors and 2 basements (parking garage) with RC structure.
The building had a fall from the bottom of the first story (Photo 25-1). Destructions of walls on the Photo
25-1 were openings for rescue works. According to the hearing from a resident who lived in the 5th floor at
the earthquake, the building sank about one minute after the earthquake and began collapsing. Photo 25-2
shows that all reinforcements of columns and bearing walls were drawn out or cut at the first floor whencollapsing. There was no damage in the basement walls for the gable plane of structure (Photo 25-3).

- 23 -

Newly opened for
rescue works

Photo 25-1 Appearance

Photo 25-2 Torn wall columns and bearing walls

Photo 25-3 Walls at basement

No.4 Others
A lot of old brick construction and Adobe structure buildings were damaged in Concepcion. Manybuildings suffered from damage in some parts or glasses were under renovation, but not so many middle
and low-rise buildings with RC structure were damaged. Photo 26-1 shows devastated details in the city.

Photo 26-1 Concepcion

2.6 Dichato, Región del Biobío
Dichato is a small fishing village on the sea, and located northern 30km away from Concepcion.
Devastated investigation for low-rise houses of SERVIU was conducted. Locations of investigatedbuildings in Dichato and Penco are shown in Figure 7.

- 24 -

DichatoNo.1 Detached houses
No.2 Miramar houses

Penco
No.1 Apartment houses

Figure 7 Investigated buildings in Dichato and Penco (tack building number on the google map)

No.1 Detached houses
Those are houses constructed by SERVIU in 2008, which steel frame and precast RC construction are
mixed (about 4.8m eave height, Photo 27-1 and Photo 27-2). Most damage of buildings was caused by
Tsunami, not the earthquake as itself.

Photo 27-1 Appearance

Photo 27-2 Precast RC construction

Trace of
TsunamiPhoto 27-3 Trace of Tsunami (Wall at the second floor)- 25 -

Photo 27-3 shows the trace of Tsunami which remained on the wall. It is imagined that the height ofTsunami was about 9m because, the altitude of the nearest house from the seashore is about 5m and thetrace of Tsunami was near the ceiling of the 2nd floor.
No.2 Miramar houses
They are houses constructed by SERVIU in 2008. The 1st story was masonry structure with bricks and the
2nd story was wooden structure (Photo 28-1). Not so big damages received by the earthquake, but the mostdamage was because of Tsunami, and wooden structure parts of the 2nd story were swept away (Photo28-2). Damages of northern part of houses were severe, and wooden structure part of the 2nd story was
deformed to south side, so it is imagined Tsunami was attacked from the north. There were foundations andgirders, but not columns at the 1st story, and vertical and horizontal reinforcements were arranged in thewalls. The size of the vertical reinforcement was about D10 (Photo 28-3).

Photo 28-1 Appearance

Photo 28-2 2nd story were swept away by
TsunamiPhoto 28-3 Vertical reinforcement

2.7 Penco, Región del Biobío
Penco is a small fishing village on the sea same as Dichato, and apartment houses constructed by SERVIU
were investigated. Investigated buildings are shown in Figure 7.
No.1 Apartment houses
This is an apartment house offered by SERVIU and has four floors (Photo 29-1). The structure is light-steel
frames and braces, and exterior walls were composed of steel folded plates. Some residents used to remove
the brace or column in a part of houses, but there was no big damage by the earthquake. Steel folded platesof exterior walls were deformed in some parts as Photo 29-2, and it is imagined that they worked properly
as earthquake resistant elements.

- 26 -

Folded plates

Photo 29-1 Appearance

Photo 29-2 Deformation of folded plates

2.8 Chillan, Región del Biobío
Investigation in Chillan was not conducted, but the church near the hotel was severely damaged (Photo30-1). Building frame is RC structure, but the steeple penetrated the roof and came down. The top ofcolonnade of a chapel and walls were also damaged (Photo 30-2 and Photo 30-3).

Photo 30-1 Church

Photo 30-2 Inside of church

Photo 30-3 Fallen steeple

2.9 Tsunami disaster(1) Constitucion, Región del Maule
The traces of Tsunami in Constitucion were shown in Photo 31-1 and Photo 31-2.

- 27 -

The traceof Tsunami

Photo 31-1 Apartment house of SERVIU near
estuary region (About 400mm high)Photo 31-2 City area

All of restaurants built at the seacoast were destroyed. Discolored plants by seawater were up to halfway ofthe cliff, and it estimated that Tsunami reached about 20 to 30m (Photo 31-3). All streetlights on the coast
were turned over from the foot to same direction (to the south). A wood chips factory near the seacoast also
received damages (Photo 31-4).

Photo 31-3 Trace of Tsunami

Photo 31-4 Seacoast area
(2) Pelluhue, Región del Maule
Pelluhue is a small settlement facing the Pacific Ocean, and located the closest point to the earthquake
source. This area was severely damaged by Tsunami, and most buildings near the coast were swept away,
except for concrete foundation and a part of walls remained (Photo 32-1). According to the residents, there
was no human suffering because they evacuated voluntarily on the hill by cars immediately after theearthquake. It is assumed that emergency drills were conducted on a routine basis, and awareness of
disaster prevention was raised. It is reported that Tsunami was not so large in the earthquake in 1960. Signs
to indicate the evacuation direction and safe places from Tsunami were settled on the road, not only in this
district but also in many places.

- 28 -

Photo 32-1 Seacoast area
(3) Dichato, Región del Biobío
Wooden structure buildings were destroyed by Tsunami and received extensive damages, and rubbles were
piled up near the seacoast (Photo 33-1). As described in 2.6, the trace of Tsunami was seen in RC and brickconstruction buildings, but building frames remained without big damages. Residents evacuated on the hill
after the earthquake and were safe, but there were some victims who went back to their houses to bringbaggage after the first wave went out, and who stayed in the vacation houses near the seacoast as tourists.
This district was under control of the military at the point of this investigation (Photo 33-2).

Photo 33-1 Seacoast area

Photo 33-2 Tent of refugees and military- 29 -

３．Features of damaged buildings
Extensive damages were observed on buildings with masonry structure as brick constructions and Adobe
structures including CM and Infilled Wall structures #7 in this earthquake. Though the masonry structure is
one of the most popular construction method around the world, not only in Central and South America but
in Asia and European countries, they have not always been excelled in performance for the earthquake
resistant, so it is reported many damages by earthquakes in the past.
As some featured cases, damages of RC wall structures were investigated. In Chile, RC wall structure is inwidespread use for building constructions, which is uncommon in Central and South America area. The
structure is similar to Japanese RC wall moment frame structural system, of which the applicable limitationis less than 15 stories and 45m high. Other than the above, there are common damage cases in urban
buildings as collapse of the soft first story buildings, and story collapse of intermediate story in high-risebuildings. Numbers of these damaged buildings are attributive, but those occurred in relatively newbuildings, and should be constructed based on the current seismic design standard of Chile (1996), so
further detailed investigations will need to be executed for solving the cause of the phenomena.
Chile always focus on seismic design of buildings and it is estimated that damages of the earthquake thistime is not big scale as Mw8.8, which seismic design force of Chilean code is about half of Japanesestandard [4]. It follows in general that the current seismic design method has performed effectively to
mitigate the damage of buildings. Here we indicate the classification of investigated damage patterns
comparing with past typical damages.
3.1 Damages of whole buildings(1) Overturned buildingThis is a case of a RC condominium collapsed, which had 15 floors (Photo 34-1, reprinted photos shown in
Chapter 2). The basements are parking garage (3.3(1) is the similar case) and the length of bearing walls
are shorter (smaller) than upper floors, so it seemed the damage at this portion brought on the overturn ofthe building (refer to Photo 39-1and Photo 39-2). A schematic illustration of multistory bearing wall thathas a large opening at basement is shown in Figure 8. The cause of collapse needs to be considered indetail.
Newly opened for
rescue works

Photo 34-1 Damage of collapse (Photo 25-1 reprinted)#7

Confined Masonry (CM) structure
After arranging reinforcements of column and stacking bricks of wall, concrete are casted incolumn using the form. Upper beam of RC is consequently built, and then masonry wall is
unified with RC tie-columns and tie-beams. Reinforcements are usually arranged in masonrywalls but sometimes without rebar. In both cases, masonry walls of CM structures are designed
as structural elements against vertical load and seismic force.
Infilled Wall structure
After framing RC columns and beams, bricks are piled up in the frame. Wall has no
reinforcement in most cases. Structural element against load and external force is RC moment
resisting frame but masonry wall.
- 30 -

Multistory bearing wall

On the ground▼G L

Under ground

CracksFigure 8 Schematic illustration of multistory bearing wall with large opening at basement(2) Collapse of intermediate story in high-rise buildingThis is an example that the intermediate story in RC high-rise building was collapsed (Photos 35-1 and35-2). Entire story collapse was observed in the front of the building, but the backside of it was a multistory
bearing wall with small opening, and the damage was small. Story collapse occurred at the floor withsetback. Information of the building structures and the investigation results did not be obtained yet, so thecause of damages should be considered after time.

Photo 35-1 Collapse of the intermediate story (Photo 23-1 reprinted)

Photo 35-2 12th floor (Photo 23-2 reprinted)
In the Great Hanshin-Awaji Earthquake, Japan, 1995, similar cases of the collapse of intermediate story
were reported (Photo 35-3). As for the cause of them, the change of structural system from SRC to RC waspointed out.

- 31 -

Photo 35-3 Collapses of intermediate story (The Great Hanshin-Awaji Earthquake, Japan, 1995)(3) Collapse of first story in RC mid-rise buildingThis is an instance that the first story in RC mid-rise building (condominium) was collapsed (Photos 36-1
and 36-2). The building shown in Photo 36-2 is the soft first story (Piloti) structure and the deformation in
the earthquake centered on the first story.
Collapse of the soft first story has been frequently reported as earthquake damages, Photo 36-3 indicatesthe case in the Great Hanshin-Awaji Earthquake, Japan, 1995, and Photo 36-4 is the case in L'Aquila
Earthquake, Italy, 2009.
In Japan, after the Great Hanshin-Awaji Earthquake, the provisions for story stiffness ratio, i.e. theevaluation for distribution of stiffness belong to the building height; have been strengthen. Additionally, thepoints to consider in seismic design of the soft first story structure are published in a technical handbook [5],[6].

Photo 36-1 Collapse of soft first story(Photo 8-1 reprinted)

Photo 36-3 Collapse of soft first story
structure (The Great Hanshin-Awaji
Earthquake, Japan, 1995)

Photo 36-2 Collapse of soft first story (Piloti)(Photo 9-1 reprinted)

Photo 36-4 Collapse of soft first story structure(L'Aquila Earthquake, Italy, 2009)- 32 -

(4) Story collapse of CM low-rise building
Photo 37-1 indicates a case that an apartment house of CM structure collapsed at the first story, and upper
stories fell down. These structures have a tendency to use same member section, bar arrangement, and wallquantity in every story; that causes the shortage of wall at the first story compared to upper, because large
opening is set to the entrance. Seismic force against building generally acts on the first story the most, so it
leads to the first story relatively breakable. Damages of CM buildings are reported in many earthquakes,
and here let me introduce a case in Pisco Earthquake, Peru, 2007 (Photo 37-2).

Photo 37-1 Collapsed first story of CM building (Photo 14-3 reprinted)

Photo 37-3 Collapsed CM buildings (Pisco Earthquake, Peru, 2007)(5) Damages of masonry structure building
Photos 38-1 and 38-2 show examples of damages of masonry structure buildings as brick constructions and
Adobe structures. As cases of recent earthquakes, for example, damage of brick construction buildings in
Sichuan Earthquake, China, 2008 (Photo 38-3), and masonry structure buildings in L'Aquila Earthquake,
Italy, 2009 (Photo 38-4) are quoted.

Photo 38-1 Damage of Adobe buildings (Photo 16-1, Photo 22-1 reprinted)- 33 -

Photo 38-2 Brick construction buildings (Photo 22-1, Photo 26-1 reprinted)

Photo 38-3 First floor collapsed brickconstruction building(Sichuan Earthquake, China, 2008)

Photo 38-4 Masonry structure(L'Aquila Earthquake, Italy, 2009)

3.2 Damages of structural members(1) Failure of RC bearing wall
Photo 39-1 shows a case that RC multistory bearing wall of a 12-story building was smashed at the first
basement level. Photo 39-2 also shows RC multistory bearing wall was smashed at the first basement levelin a building, which has 18 floors and 2 basements. These cases are unknown in past other earthquake, andit might be the specific failure type in this earthquake. In general, the common failure type of RC bearing
wall is diagonal shear crack.

Photo 39-1 Smashed RC wall
(Photo 1-2 reprinted)

Photo 39-2 Smashed RC wall
(Photo 2-3 reprinted)

Apartment houses newly-built in urban city area are designed to set up the opening in a part of multistory
bearing wall to secure the drive zone at the basement which is used as parking garage (Figure 8). Photo
39-1 is corresponding to the left-side wall underground shown the image in Figure 8. Failure on the Photos
occurred because large tensile axial force and shear force were affected on.
(2) Flexural failure of RC column (wall column)
Photo 40-1 shows wall columns (flat shaped columns) of RC mid-rise building, and the big damage- 34 -

occurred on the capital. These wall columns are imagined that deformation centered to the capital after
bending to weak axis direction, and could not support the vertical load with losing the horizontal strength.
Similar damages of columns are confirmed in Sichuan Earthquake, China, 2008 (Photo 40-2), but thedamage of wall column is presumed the specific failure type in Chile.

Photo 40-1 Flexural hinges on wall columns(Photo 9-3 reprinted)

Photo 40-2 Flexural hinge on column capitals(Sichuan Earthquake, China, 2008)(3) Failure type of RC beama. Shear failure of beam
Photo 41-1 shows a example that beams on the top of the door opening in RC mid-rise building failed inshear. The causes of the failure are presumed that stress is easy to be concentrated at short spanned beam inearthquake, and flexural strength of it become strong.
Similar failure of short spanned beam at the stairway of a hospital was confirmed in Niigata-ken Chuetsu
Earthquake, Japan, 2005 (Photo 41-2).

Photo 41-1 Shear failure of short spanned
beam (Photo 9-3 reprinted)

Photo 41-2 Shear cracks of short spanned
beam (Niigata-ken Chuetsu Earthquake,Japan, 2005)

b. Failure of anchorage of beams
Photo 42-1 shows a beam at the top story of CM building failed around the lap joint of reinforcements andfallen down to out-of–plane. This building was constructed more than 20 years ago and, the standard fordesign and construction at that time are not recognized. In general, the location and length of the lap joint
should be designed so that tensile stresses of which main reinforcements carry can be transmitted. It is
imagined that the location and length of lap joint in the fallen beam are not appropriate and the stresstransmission is not performed adequately (Photo 42-2).

- 35 -

Photo 42-1 Failed beam at the top of thetransverse wall (Photo 15-3 reprinted)

Photo 42-2 Main reinforcement at same
joint point (Photo 15-4 reprinted)(4) Failure of RC beam-column joint and othersa. Failure of RC beam-column joint
Photo 43-1 shows the failure of beam-column joint in RC mid-rise building, and Photo 43-2 is the same of
CM building. In both cases, hoops were not used in the joint, and the section of it was small, then they led
to the failure.
Similar damages of beam-column joint were investigated in Sichuan Earthquake, China, 2008 (Photo 43-3),
and in L'Aquila Earthquake, Italy, 2009 (Photo 43-4).

Photo 43-1 Failure of beam-column joint(Photo 7-2 reprinted)

Photo 43-2 Failure of beam-column joint(Photo 14-4 reprinted)

Photo 43-3 Failure of beam-column joint(Sichuan Earthquake, China, 2008)

Photo 43-4 Failure of beam-column joint(L'Aquila Earthquake, Italy, 2009)b. Failure of joint among buildings
Photo 44-1 shows the failure of joint among buildings, one is 12-story building and another is 2-story
building. Vibration of building in earthquake is depending on the natural period, so if adjacent buildings,
which have different height, are situated, they are crashed each other and become the cause of the failure.

- 36 -

Expansion joint is laid on among buildings ordinarily in Japan.

Photo 44-1 Joint among buildings (Photo 6-2 reprinted)

3.3 Nonstructural materials(1) Damage of brick wall
Photo 45-1 is the damage of brick walls in RC high-rise building (Infilled Wall structure). These walls aredesigned as nonstructural wall, so some damages must be allowed, but measures should be taken in order toprevent falling off in out-of-plane direction even if cracks occurred by earthquake. Similar damages arereported in many earthquakes, Photo 45-2 is seen in Sichuan Earthquake, China, 2008 and Photo 45-3 isseen in L'Aquila Earthquake, Italy, 2009.

Photo 45-1 Cracks on brick walls (Photo 5-2 reprinted)

Photo 45-2 Collapse of nonstructural wall
(Sichuan Earthquake, China, 2008)

Photo 45-3 Collapse of brick walls(L'Aquila Earthquake, Italy, 2009)(2) Damages of RC nonstructural materials
Photo 46-1 shows a roller-supported beam at one end fell down the place 7 to 8m away because of theearthquake. Photos 46-2 and 46-3 are the nonstructural walls of RC office buildings dropped. In both cases,
heavy RC materials are used, and such phenomena bring a risk to get passer-by and vehicles involved in
accidents. Many decoration materials are attached to the external walls on buildings in this investigation.

- 37 -

Further caution should be needed in design and construction from here on.
Roller support

Bar arrangement ofjoint parts
Photo 46-1 Drop of beam (Photo 12-5 reprinted)

Photo 46-2 Collapse of External wall
(Photo 7-1 reprinted)

Photo 46-3 Collapse of External wall
(Photo 19-1 reprinted)(3) Damages of glasses and ceiling
Photo 47-1 shows the situation of broken and scattered windows of outer plane in a mid-rise building.
Ceiling materials fell down in the terminal building of Santiago international airport (Arturo Merino
Benítez International Airport, Photo 47-2). A part of the terminal was unusable due to those phenomena anddamages on facilities, then some operation were conducted in an outdoor camp at the time of theinvestigation.
Fallen ceiling materials at the large-scale building were also reported as the terminal building damage inKushiro airport at the Tokachi-oki Earthquake, Japan, 2003 (Photo 47-3).

Photo 47-1 Broken and scattered windows (Photo 20-2 reprinted)- 38 -

Photo 47-2 Fallen ceiling panels at Santiago international airport

Photo 47-3 Fallen ceiling panels at Kushiro airport(Tokachi-oki Earthquake, Japan, 2003;
photo offered by Kushiro Airport Terminal Building Co. Ltd. [7])Acknowledgement:
We would like to express our special thanks to people involved of JICA who provided logistical support tothis dispatch of expert and those of JICA in Chile who set up organizations concerned in Chile andprovided accommodations for investigative activities.
We gained the much cooperation from everyone concerned that belong to the faculty of constructions(structures) in University of Chile and Católica University, regarding information provision of damagedbuildings and accompanying to the site in the investigation. Building Research Institute / International
Institute of Seismology and Earthquake Engineering has been carrying out the trainings in seismology andearthquake engineering to young researchers and engineers of developing countries over 50 years from1960 with the collaboration of JICA. So far 42 trainees from Chile have participated these training courses,
and they take lead the role in their specialized field after returning. Relationship with the former trainees
functioned effectively in the investigation. We would like to extend our deepest gratitude to everyone
concerned.

References:
1. USGS Homepage: http://earthquake.usgs.gov/earthquakes/eqinthenews/2010/us2010tfan/
2. USAID/OFDA: Fact Sheet #16, USAID/OFDA bulletins appear on the USAID web site at
http://www.usaid.gov/our_work/humanitarian_assistance/disaster_assistance/
3. R. BOROSCHEK, P. SOTO, R. LEON, D. COMTE: INFORME PRELIMINAR, RED NACIONAL
DE ACELEROGRAFOS, TERREMOTO CENTRO SUR CHILE, 27 DE FEBRERO DE 2010,
INFORME PRELIMINAR N° 4, FACULTAD DE CIENCIAS FISICAS Y MATEMATICAS,
UNIVERSIDAD DE CHILE, 5 DE MARZO 2010, http://www.terremotosuchile.cl
4. Taiki Saito: Earthquake-resistance standards in Chile, NCh433 (1996) (in Japanese), BRI web site at
http://iisee.kenken.go.jp/special/20100227chile/seismic_code_chile.pdf- 39 -

5. Kheir-Eddine Ramdane, Koichi Kusunoki, Masaomi Teshigawara and Hiroto Kato: Non-Linear
Numerical Analyses To Improve The Seismic Design Method for Soft First Story RC Building, 13th
World Conference on Earthquake Engineering, Vancouver, B.C., Canada, 2004, Paper No. 2224
6. Manual for Structural Design of Buildings with Commentary of Building Standard Law of Japan(Annex 1-6), August, 2007 (in Japanese)
7. National Institute for Land and Infrastructure Management, Building Research Institute: Investigation
report regarding ceiling damages at the airport terminal building in Tokachi-OKI earthquake in 2003.
(in Japanese), NILIM web site at http://www.nilim.go.jp/engineer/index.html- 40 -