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Yi-Hsuan Tu, National Cheng Kung University
Adrian Tola, Virginia Tech University
Forrest Lanning, Miyamoto International
EERI / Hemant Kaushik
April 16, 2016 Ecuador Earthquake
EERI Learning from Earthquakes Briefing Webinar
EERI team:
Forrest Lanning, Mei Kuen Liu,
Arturo Schultz, Gabriela Haro,
Hector Monzon, Alberto Jose Monzon, Adrian Tola
PERFORMANCE OF HOSPITALS
Adrian Tola T.
Virginia Tech
EERI LFE Briefing for the April 16, 2016 Ecuador Earthquake
Hospitals visited
Chone
Bahia de Caraquez
Bahia de
Caraquez
Chone
Manta
Portoviejo
Portoviejo
Manta
Hospital
City
Day of visit
(days after earthquake)
IESS
Manta
05/09/2016 (23)
No operational
IESS
Portoviejo
05/10/2016 (24)
Operational
SOLCA
Portoviejo
05/10/2016 (24)
1st floor operational, others NOT
Miguel Hilario Alcivar
Bahia de Caraquez
05/11/2016 (25)
No operational
Napoleon Davila
Chone
05/12/2016 (26)
No operational
Status
Structural System
Typical: - Concrete Moment Frames at all bays (not just at the perimeter), with concrete
“waffle” slab.
IESS
(Manta)
-
Concrete Moment Frames (particularly at the exterior bays) are usually
infilled with unreinforced masonry (URM).
-
Interior partition walls are also made of URM, with very week attachments to
resist out of plane forces.
SOLCA
(Portoviejo)
Structural System
-
Old hospitals used to be built in segments; where each of them
could have different height, structural system, and age.
Napoleon Davila
(Chone)
Bahia
Bahia
Hospital IESS (Manta)
Roof of
1st story
www.eldiario.com.ec
MANTA
2.0
AMNT-N
SA (g)
1.5
AMNT-E
1.0
0.5
0.0
0
1
2
3
Period (sec)
Roof of
1st story
●PGA from station in Manta: 0.52 g (Ref. only)
Report # 18. AMNT Station.
Geophysics Institute of the National Polytechnic School (Ecuador)
4
● Severe cracking or total collapse of several interior and exterior walls made of
unreinforced masonry.
● Lack of proper attachment for mechanical equipment.
Hospital IESS (Portoviejo)
PORTOVIEJO
2.5
APO1-E
APO1-N
SA (g)
2.0
1.5
1.0
0.5
0.0
0.0
1.0
2.0
3.0
Period (sec)
4.0
Courtesy of Hector Monzon
●PGA from station in Portoviejo: 0.38 g (Ref. only)
Report # 18. APO1 Station.
Hospital IESS (Portoviejo)
● Operational now. Shut down for short time after the earthquake.
● No cracks observed in stairs / corridor / hallways.
● Crack observed at seismic joint.
Multy-story building
1 story building
Roof of
1st story
http://www.viewphotos.org/ecuador
Hospital SOLCA
(Portoviejo)
Photo taken before the earthquake
Hospital SOLCA (Portoviejo)
No ties
observed in
this region
● Picture on the left shows pieces of interior wall in the floor, due to inappropriate
construction system of these walls.
● Picture on the right shows structural damage in one of the columns.
Upper floors
1 story building
Hospital Miguel Hilario Alcivar (Bahia)
Shear Walls
Front view
Shear Walls
Lateral view
● This hospital was retrofitted in 2000 after a M7.2 earthquake in Bahia in 1998.
● Part of the seismic retrofit included the cast of 6 shear walls, and jacketing of some concrete
columns at the perimeter.
Steel
Angle
● No
attachment
of partition
wall.
Hospital Miguel Hilario
Alcivar (Bahia)
● Severe cracking of URM walls was observed in the 1st
floor; however, several off these walls did not fall down
towards the ground. Smaller drifts due to rigidity of
shear walls might have influence on this behavior ??
Upper floors
● Minor damage in some walls at levels other than the 1st one.
Hospital Napoleon Davila
(Chone)
CHONE
2.0
ACHN-N
SA (g)
Block 1
Block 2
ACHN-E
1.5
1.0
0.5
Block 3
0.0
0.0
1.0
2.0
Period (sec)
Block 3
3.0
4.0
Block 2
●PGA from station in Chone: 0.37 g (Ref. only)
Report # 18. ACHN Station.
Block
1
Block 2
Block 3
Hospital Napoleon Davila (Chone)
●Significant damage in Block 2. due to crashing with adjacent blocks.
Block 3
Block 2
Block 1
●Permanent Deformation in Block 2
Upper floors
Level 3
Level 4
Level 5
Hospitals - Conclusions
● Poor performance of interior/exterior URM walls. Major damage was concentrated
at the first two stories for multi-story building segments, with the exception of the
Hospital IESS in Manta, where all the stores had poor behavior of URM.
● Minor damage observed in structural system (beams & columns).
● Good performance of seismic retrofitting techniques, as observed in the Hospital
Alcivar in Bahia.
● Damage caused by inadequate separation at seismic joints could have been avoided.
IMPORTANT: Few casualties within these hospitals at the time of the earthquake.
THOUGHTS: - Level of damage in hospitals that implies DEMOLITION ??
- Costs of Retrofit vs. New Construction vs. INSTRUMENTATION ??
- Awareness of structural engineers in using URM for partition walls ???
OTHER TEAMS: - Eduardo Miranda, Stanford University
- Enrique Morales, University of Buffalo.

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