Although it is a residential building, small commercial shops also occupy the ground floor. The total area of the building is 1784 sqm. The ground floor, 195 sqm, is smaller than the other stories, 227 sqm. There is no underground basement. The foundation...

Prepared By: Miguel Robles
Occupancy: Residential
Year Built: 1984
Height: 24 m
Number of stories: 8
Stories below ground: 0
Size: 1784 sqm
Original Code: 1975 Turkish
Modification: Unknown
Year Modified:
Code of Modification:
Lateral Load System: Moment Frame and Shear Wall Combination
Other Load System:
Vertical Load System: Slabl_Beams_Columns
Other Vertical Load System:
Foundation : Other
Other Foundation : two-way continuous strip footing
Country: Turkey
State: Ceyhan
City: Ceyhan
Street:
Latitude: 37.0317
Longitude: 35.82275


 

8-story apartment building

Earthquake Information

 

 

Earthquake Date 35973
Moment Magnitude 6.3
Epicentral Distance 49
Local Intensity VIII MMI
Site Description "The city is located on a large alluvial plane formed by the Ceyhan river. The soil formation consists of a thin vegetable soil on top (< 1 m), a sand and stiff clay layer of thickness 1-3 m below, and a deep silty clay layer at the bottom. Water table depth varies between 1.5-3.5 m". (Sucuoglu, Gur and Gulkan, 2000).
PGA Lateral 0.273 (g)
PGA Vertical 0.086 (g)
SaT 0.94g in the north-south direction, 0.65g in the east-west direction.
Ground motion recording stations Ceyhan
Distance to station None
Station Latitude 37.05
Station Longitude 35.81
Ground Motion Summary "Adana-Ceyhan earthquake occurred at 4:56 PM local time on 27 June 1998. The epicentral coordinates of the main shock (Ms=6.2) were reported as 36.95 N and 35.31 E, and the focal depth as 23 km which is followed by numerous aftershocks. The strike direction of the causative Misis fault is in the left lateral sense, with a rupture directivity from Southwest to Northeast toward Ceyhan. Accordingly, earthquake shaking was felt most strongly in Ceyhan with the evidence of heavy damage in the city (MM intensity VIII). The corrected peak ground acceleration components recorded by the Ceyhan station are 223 mg in the NS direction, 0.273 mg in the EW direction and 86 mg in the vertical component. When these accelerations are integrated and resolved, peak ground velocities of 30 cm/s and 25 cm/s and peak ground displacements of 8 cm and 12 cm are obtained in the longitudinal and transverse directions to the fault respectively". (Sucuoglu, Gur and Gulkan, 2000).

 

Damage Information

 

 

Performance summary

The building's damage rating was rated to be in the moderate damage range. Most of the damage was concentrated in the beams. Shear walls and some columns were lightly damaged. Brick partition walls were also damaged. The was crushing and spalling of the concrete cover. There is no evidence of soft story behavior in the building. (Gur and Sucuoglu, 2000).

Damage state description

The most outstanding feature of the observed damage is the similar beam damage pattern repeated at the ground, 1st, 2nd, 3rd and 4th story levels. Damages in the brick partition wall at these stories were also similar. Shear walls and some columns were lightly damaged at the lower stories. The most severe damage was observed at the 1st story. (Gur and Sucuoglu, 2000).

Summary of causes of damage

Distribution of the damaged beams and brick partition walls indicates that the first five stories displayed considerable drift during the earthquake. The observed damage may be attributed to: 1. Relatively low lateral stiffness. 2. Inadequate confining reinforcement. 3. Smooth reinforcing bars. 4. Poor workmanship quality. (Gur and Sucuoglu, 2000).

Observed Design and Construction Characteristics

 

Construction Quality

MaterialsNotesContribution to Damage
Concrete 14 MPa concrete strength
Reinforcing steel Smooth bars

ExecutionNotesContribution to Damage
Conveyance/placement of concrete Poor workmanship quality
Rebar Poor workmanship quality
Field variance with design documents Poor workmanship quality
OtherNotesContribution to Damage
Other Factors Construction Quality

Configuration

Plan IrregularitiesNotesContribution to Damage
Torsion
Perimeter boundary
Diaphragm
Out-of-plane offsets in lateral resisting system
Non-orthogonal systems

Vertical IrregularitiesNotesContribution to Damage
Soft story
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 The first five stories displayed considerable drift

Load PathNotesContribution to Damage
Collectors/Struts
Anchorage of nonstructural elements
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 were lightly damaged
Flexural strength Columns were lightly damaged
Axial load ratio
Vertical load columns drift capacity
Interference of frame action by infill Columns were lightly damaged

BeamsNotesContribution to Damage
Strength relative to columns Most of the damage was concentrated in the beams
Shear controlled behavior
Continuity of longitudinal reinforcing
Loss of vertical capacity
Interference of frame action by infill beams

JointsNotesContribution to Damage
Interior
Exterior
Corner

OtherNotesContribution to Damage
Other Factors Lateral Load Resisting System-Frames

Lateral Load Resisting System‐Shear Walls

ShearNotesContribution to Damage
Diagonal tension/compression Shear walls were lightly damaged
Sliding Shear
Flexure/shear Shear walls were lightly damaged

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
Interference with frame action
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

Improved Performance

Other Retrofit or Repair

Performance Level

Other

Hazard Level

Unknown

Retrofit or Repair Code

Other

Other Retrofit or Repair Code

1997 Turkish

Lateral Analysis

Nonlinear static

Other Lateral Analysis

Design Strategy

In the strengthened frame, the lateral load is resisted the most by the newly added shear walls, which are properly reinforced. The contribution of existing members to lateral resistance starts after the new shear walls yield. The analyses show that the added shear walls improve the performance of the structure only to the minimum acceptable level. The building is expected to respond in structural stability performance level under design earthquake. (Gur and Sucuoglu, 2000).

Retrofit Summary

Cast-in place reinforced concrete shear walls were added to the existing system for strengthening. The ratio of the shear wall area to the basement plan area is 2.9% in the short direction and 1.9% in the long direction. The added shear walls raised the strength level and the deformation capacity at the ultimate stage by 47% and 22%, respectively. (Gur and Sucuoglu, 2000).

References

 

Gur, Turel; Sucuoglu, Haluk; 2000. "Seismic rehabilitation of 108 R/C buildings in Ceyhan after the 27 June 1998 Adana-Ceyhan earthquake". Middle East Technical University (METU), Earthquake Engineering Research Center (EERC), Report no. METU/EERC 2000-01, Ankara, Turkey.


http://db.concretecoalition.org/static/data/6-references/TURK008_Reference_01.pdf
Haluk SUCUOGLU, Trel GR, Polat GLKAN, 2000. "The Adana-Ceyhan Earthquake of 27 June 1998 - Seismic Retrofit of 120 R/C Buildings". The 12th World Conference on Earthquake Engineering, Auckland, New Zealand.


http://db.concretecoalition.org/static/data/6-references/TURK008_Reference_02.pdf
Eythymios LEKKAS, Emmanuel VASSILAKIS, 2000. "The Adana Earthquake (Turkey) - Seismotectonic Framework, Geodynamic Phenomena, Impact on the Structured Environment". The 12th World Conference on Earthquake Engineering, Auckland, New Zealand.


United States Geological Survey (USGS), 2008. "USGS ShakeMap: Adana-Ceyhan, Turkey". ShakeMap Atlas, 2012. http://earthquake.usgs.gov/earthquakes/shakemap/atlas/shake/199806271355/