The hospital campus is comprised of approximately fourteen buildings, many with separation joints between and inside them. This creates several more independent structural units. Most units are three to five story RC frames, with hollow clay bock walls an...

Prepared By: Sarah Bettinger
Occupancy: HospitalHealthcare
Year Built: 1972
Height:
Number of stories: 3
Stories below ground: 2
Size:
Original Code: 1962
Modification: Other
Year Modified: 2003
Code of Modification: Non-structural elements secured
Lateral Load System: Frames with Masonry Infill
Other Load System: Infill hollow clay block walls, not designed as structural elements.
Vertical Load System: Slabl_Beams_Columns
Other Vertical Load System:
Foundation : Other
Other Foundation :
Country: Italy
State: Abruzzo
City: Coppito, L'Aquila
Street: Via Vetoio, Coppito 67100 L'Aquila, Abruzzo
Latitude: 42.3661
Longitude: 13.3527


 

San Salvatore Hospital

Earthquake Information

 

 

Earthquake Date 39909
Moment Magnitude 6.3
Epicentral Distance 4
Local Intensity VII EMS
Site Description
PGA Lateral 0.51 (g)
PGA Vertical None (g)
SaT
Ground motion recording stations The closest accelerometer on soil conditions similar to the site was station AQG (at site Colle dei Grilli). In the immediate vicinity were five other stations: AQV, AQM, AQF, AQP, and AQK.
Distance to station 2
Station Latitude None
Station Longitude None
Ground Motion Summary According to the USGS (United States Geological Survey), the epicenter of the earthquake was located at 42.334N, 13.334E and a depth of 8.8km.

 

Damage Information

 

 

Performance summary

The RC frames generally performed adequately. A safety evaluation in the morning after the earthquake identified serious structural damage in three of the hospital buildings. The entire hospital was evacuated, and remained closed until May of 2009, when normal operations continued.

Damage state description

Between 4 and 8 of the lower level columns at the entry portico of the main and emergency entrances suffered partial failure without collapse or noticeable deflection at the tops of these frame elements. The concrete had spalled, the inner concrete core of the column appeared to have a slight offset, and the vertical reinforcement was exposed and buckled. Plastic hinges and shear failures were evident. Masonry infill caused short column damage at the pharmacy building, and the bearing capacity of those columns was severely compromised. The structural joints within the buildings were not appropriately designed for shock induced movement, and the resultant pounding between sides of the joint caused localized damage. Localized damage was detected at the last flight of inner stairs between buildings 2A and 2B. Widespread X-cracking of infill panels and exterior veneers was documented, indicating shear failure.

Summary of causes of damage

1. Column ties seem to have been omitted at the locations where the lower level columns were damaged at the entrance, though reinforcing had been intended in the original design. 2. Infill masonry panels caused a short column effect in some of the columns of the pharmacy (Building 10). 3. Poor structural detailing of certain seismic joints led to localized damage. Frequently, seismic separations were not achieved by bringing separate-but-adjacent vertical members up from a common footing, but rather, by having adjacent upper-level portions of the building supported on a common wall or common column. 4. Structural joint detailing made use of half-joints in beams and slabs. These types of joints performed erratically and generally lacked adequate joint seating material. 5. The concrete frame did not perform well in the locations where it, rather than the masonry infill, resisted the lateral load. 6. Nonstructural veneer was dislodged by pounding at joints.

Observed Design and Construction Characteristics

 

Construction Quality

MaterialsNotesContribution to Damage
Concrete Non-destructive testing indicates that the concrete of the structures generally ranges from medium to good quality, both in terms of strength and modulus of elasticity (Casarotti, et al., 2009).
Reinforcing steel Non-destructive testing indicates that the steel is generally of good quality, with, in some cases, a smooth surface and in others, improved adherence (Casarotti et al., 2009).

ExecutionNotesContribution to Damage
Conveyance/placement of concrete
Rebar Insufficient ties in beams (Price et al., 2012). Insufficient concrete cover (Casarotti, et al., 2009).
Field variance with design documents Column tie reinforcement was either widely spaced or nonexistent at observed locations, though it was intended in the 1967 design documents (Price, et al., 2012).
OtherNotesContribution to Damage
Other Factors Construction Quality

Configuration

Plan IrregularitiesNotesContribution to Damage
Torsion
Perimeter boundary Several of the buildings have plan irregularities.
Diaphragm
Out-of-plane offsets in lateral resisting system
Non-orthogonal systems

Vertical IrregularitiesNotesContribution to Damage
Soft story Lower level of portico acted as a soft story. The levels above had significant infill masonry (Price, et al., 2012).
Weak story
Geometric variablility of lateral resisting system
In-plane discontinuity of lateral resisting system
Mass distribution
Setback
Change in stiffness

OtherNotesContribution to Damage
Other Factors Configuration

Lateral Load Resisting System‐General

StrengthNotesContribution to Damage
Overall lack of strength

StiffnessNotesContribution to Damage
Extreme Flexibility

Load PathNotesContribution to Damage
Collectors/Struts
Anchorage of nonstructural elements "Complete detachment of coating of many of the ground floor tiled walls", damage and detachment of masonry veneer walls (Casarotti, et al., 2009).
Out-of-plane capacity of walls
Diaphragm chords
Diaphragm openings

OtherNotesContribution to Damage
Other Factors Lateral Load Resisting System-General

Lateral Load Resisting System‐Frames

ColumnsNotesContribution to Damage
Shear strength Columns at pharmacy location suffered damage typical of short column behavior (Price et al., 2012).
Flexural strength Columns at entrance portico suffered soft story failure.
Axial load ratio
Vertical load columns drift capacity
Interference of frame action by infill Short column behavior at pharmacy columns caused by "infill masonry between the columns, capped by a rigid concrete wall cap" (Price et al., 2012).

BeamsNotesContribution to Damage
Strength relative to columns Strong beam, weak column mechanism found during building survey (Casarotti, et al., 2009).
Shear controlled behavior
Continuity of longitudinal reinforcing
Loss of vertical capacity
Interference of frame action by infill beams

JointsNotesContribution to Damage
Interior Structural joint detailing made use of half-joints in beams and slabs,... [which] performed erratically and generally lacked adequate seating material (Price, et al., 2012). "Structural joints were inappropriate for shock induced movements" (Casarotti et al., 2009).
Exterior
Corner

OtherNotesContribution to Damage
Other Factors Lateral Load Resisting System-Frames "[In the basement of Building 1, there was] moderate damage in some beams as a result of the relative movement of the Gerber half joint" (Casarotti et al., 2009).

Lateral Load Resisting System‐Shear Walls

ShearNotesContribution to Damage
Diagonal tension/compression
Sliding Shear
Flexure/shear

FlexureNotesContribution to Damage
Compression zone buckling capacity
Discontinuity of wall
Boundary reinforcing fracture/buckling
Boundary Reinforcing at openings

OtherNotesContribution to Damage
Other Factors Lateral Load Resisting System-Shear Walls

Lateral Load Resisting System‐Infills

InfillsNotesContribution to Damage
Unreinforced Researchers concluded that "primary lateral resistance was provided by unreinforced hollow clay tile infill masonry. The majority of this infill was generally undamaged" (Price, et al., 2012).
Interference with frame action "The concrete frame did not perform well in the locations where it, rather than the infill, resisted the lateral load" (Price et al., 2012).
Out of plane
Attachment to framing

OtherNotesContribution to Damage
Other Factors Lateral Load Resisting Systems-Infills

Lateral Load Resisting System‐Other

FoundationsNotesContribution to Damage
Liquefaction
Pounding
Surface Rupture

OtherNotesContribution to Damage
Pile/Pier tension capacity

MiscellaneousNotesContribution to Damage
Spread footing capacity
Other Factors Lateral Load Resisting Systems-Other-Foundations

OtherNotesContribution to Damage
Other Factors Lateral Load Resisting Systems-Other-Misc

Repair and Retrofit Information

 

Type of Retrofit or Repair

Unknown

Other Retrofit or Repair

Performance Level

Unknown

Hazard Level

Unknown

Retrofit or Repair Code

Unknown

Other Retrofit or Repair Code

Lateral Analysis

Unknown

Other Lateral Analysis

Design Strategy

Retrofit Summary

References

 

http://eqs.eeri.org/resource/1/easpef/v28/i1/p239_s1?isAuthorized=no
Price, H. J., De Sortis, A., and Schotanus, M., 2012. Performance of the San Salvatore Regional Hospital in the 2009 L'Aquila Earthquake,Earthquake Spectra28, 239 -256.


http://earthquake.usgs.gov/earthquakes/eqinthenews/2009/us2009fcaf/
United States Geological Survey (USGS), 2012.Magnitude 6.3- Central Italy. (Accessed: 24 July 2012)


http://www.progettazionesismica.it/index.php?option=com_content&view=article&id=15&Itemid=28
Casarotti, C., Pavese, A., and Peloso, S. 2009. Seismic Response of the San Salvatore Hospital of Coppito (L'Aquila) during the earthquake of April 6th 2009,Progettazione SismicaNo 3, 159-172.


http://www.istructe.org/webtest/files/b8/b8df351b-a28b-4375-9d5a-20afd9be569b.pdf
Rosetto, T., Peiris, N., Alarcon, J., et al. 2009. The L'Aquila, Italy earthquake of 6 April 2009. A preliminary field report by EEFIT, United Kingdom Earthquake Engineering Field Investigation Team (EEFIT)


http://vdv.mceer.buffalo.edu/vdv/index.php?selectedEventId=2
Virtual Disaster Viewer (VDV) 2012.Viewing Event: 2009 L'Aquila Earthquake. (Accessed: 1 August 2012).


http://www.progettazionesismica.it/index.php?option=com_content&view=article&id=15&Itemid=28
Cosenza, E., Manfredi, G., Verdedame, G. M. 2009. Reinforced concrete buildings,Progettazione SismicaNo 3, 131-147.