02-22-2023, 03:20 PM
PRELIMINARY REPORT on Failures of Multistorey Buildings
in Turkey and Syria Due to the Μ 7.8 and Μ 7.5 Earthquakes
PART A: Structural Collapse and Interpretation
by Evangelia GARINI and George GAZETAS
Based on the following photos, and our experience from the Kocaeli (1999)
earthquake, we draw some conclusions regarding the unprecedented extent of damage.
In addition to the very strong seismic shaking, with PGAs in the order of at least 0.7 g – 1 g,
the following structural deficiencies (that are clearly identified in these photos and are
evident in perhaps all the collapsed buildings) were truly fatal:
1. Very thin columns, but rather thick slabs
2. Very inadequate steel reinforcement (in size and number of longitudinal bars)
3. Transverse reinforcing bars of inadequate density and improperly tied
4. NO beams !! Slabs constracted directly on columns, without continuity of the
longitudinal Rebars, and no proper joints
5. Nowhere to be seen Shear Walls, even in > 10 story buildings
(For comparison, a typical 2-story building in Cephalonia, Greece, is shown ― from an
area of similar seismicity as the region inflicted by the 7.8 earthquake.)
Numerous buildings without any beam, with small size columns (inappropriate even for 1-story buildings in a region of moderate seismicity).
Transverse reinforcement almost effectively non-existing… it was untied, leading the inadequate longitudinal rebars to buckle.
without any beams, with small size columns (inappropriate even for 1-story buildings in a region of moderate seismicity). It is a miracle that
it did not fully collapsed.
EXTREMELY STRONG GROUND SHAKING, PERHAPS LOCALLY SOIL-AMPLIFIED
DEFFECTIVE STRUCTURAL SYSTEMS WITH SEVERAL FATAL TECHNICAL FAULTS, as follows:
1. Very thin columns, but rather thick slabs
2. Very inadequate steel reinforcement (in size and number of longitudinal bars)
3. Transverse reinforcing bars of inadequate density and improperly tied)
4. NO beams !! Slabs directly on columns, without continuity of Rebars, and no proper
connection
5. Nowhere to be seen Shear Walls, even in > 10 story buildings
for more detail download
in Turkey and Syria Due to the Μ 7.8 and Μ 7.5 Earthquakes
PART A: Structural Collapse and Interpretation
by Evangelia GARINI and George GAZETAS
Based on the following photos, and our experience from the Kocaeli (1999)
earthquake, we draw some conclusions regarding the unprecedented extent of damage.
In addition to the very strong seismic shaking, with PGAs in the order of at least 0.7 g – 1 g,
the following structural deficiencies (that are clearly identified in these photos and are
evident in perhaps all the collapsed buildings) were truly fatal:
1. Very thin columns, but rather thick slabs
2. Very inadequate steel reinforcement (in size and number of longitudinal bars)
3. Transverse reinforcing bars of inadequate density and improperly tied
4. NO beams !! Slabs constracted directly on columns, without continuity of the
longitudinal Rebars, and no proper joints
5. Nowhere to be seen Shear Walls, even in > 10 story buildings
(For comparison, a typical 2-story building in Cephalonia, Greece, is shown ― from an
area of similar seismicity as the region inflicted by the 7.8 earthquake.)
Numerous buildings without any beam, with small size columns (inappropriate even for 1-story buildings in a region of moderate seismicity).
Transverse reinforcement almost effectively non-existing… it was untied, leading the inadequate longitudinal rebars to buckle.
without any beams, with small size columns (inappropriate even for 1-story buildings in a region of moderate seismicity). It is a miracle that
it did not fully collapsed.
EXTREMELY STRONG GROUND SHAKING, PERHAPS LOCALLY SOIL-AMPLIFIED
DEFFECTIVE STRUCTURAL SYSTEMS WITH SEVERAL FATAL TECHNICAL FAULTS, as follows:
1. Very thin columns, but rather thick slabs
2. Very inadequate steel reinforcement (in size and number of longitudinal bars)
3. Transverse reinforcing bars of inadequate density and improperly tied)
4. NO beams !! Slabs directly on columns, without continuity of Rebars, and no proper
connection
5. Nowhere to be seen Shear Walls, even in > 10 story buildings
for more detail download
