BRI Confidential

Strong Ground Motions of the 2023
Turkey Earthquakes

IISEE, Building Research InstituteFeb. 13, 2023

Distribution of epicenters（from 1:17 on Feb. 6, 2023 until 1:17 on Feb. 8, 2023）

BRI Confidential

2nd Event (M7.5) occurred at 10:24 on Feb. 6, 2023(UTC)

1st Event (M7.8) occurred at 1:17 on Feb. 6, 2023(UTC)https://tadas.afad.gov.tr/

BRI Confidential

Distribution of PGVs（the 1st event (M7.8))

Epicenter of the 1st event (M7.8)
TK3123

TK3138
TK3139https://tadas.afad.gov.tr/

Distribution of PGVs（the 2nd event (M7.5))

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Epicenter of the 2nd event (M7.5)
TK4612https://tadas.afad.gov.tr/

BRI Confidential

Acc. (cm/s²)

1000

Acceleration

500

NS (peak: -655.6 cm/s²)

0Pseudo Velocity Response (h=5%)
BSLJ(SoilType2)
NS
EW
UD

400

-1000
1000

EW (peak: -593.9 cm/s²)0-10001000

UD (peak: 867.6 cm/s²)0-1000pSv (cm/s)

Acc. (cm/s²)

Acc. (cm/s²)

Ground motion at TK3123（the 1st event (M7.8))

300

200

100

001020304050
Time (s)2023/02/06 01:18:20 at 3123: Kahramanmaras_Pazarck_Turkiye, Intensity: 6.3

600246Period (s)810BRI Confidential

Acc. (cm/s²)

1000

Acceleration

500

NS (peak: -888.7 cm/s²)

0Pseudo Velocity Response (h=5%)
BSLJ(SoilType2)
NS
EW
UD

400

-1000
1000

EW (peak: -746.7 cm/s²)0-10001000

UD (peak: 1296.3 cm/s²)0-1000pSv (cm/s)

Acc. (cm/s²)

Acc. (cm/s²)

Ground motion at TK3138（the 1st event (M7.8))

300

200

100

001020304050
Time (s)2023/02/06 01:18:20 at 3138: Kahramanmaras_Pazarck_Turkiye, Intensity: 6.7

6002

46Period (s)810BRI Confidential

Acc. (cm/s²)

1000

Acceleration

500

NS (peak: -577.1 cm/s²)

0Pseudo Velocity Response (h=5%)
BSLJ(SoilType2)
NS
EW
UD

400

-1000
1000

EW (peak: 504.8 cm/s²)0-10001000

UD (peak: 378.6 cm/s²)0-1000pSv (cm/s)

Acc. (cm/s²)

Acc. (cm/s²)

Ground motion at TK3139（the 1st event (M7.8))

300

200

100

00102030
4050Time (s)2023/02/06 01:18:20 at 3139: Kahramanmaras_Pazarck_Turkiye, Intensity: 6.2

600246Period (s)810BRI Confidential

Acc. (cm/s²)

1000

Acceleration

500

NS (peak: 635.4 cm/s²)

0Pseudo Velocity Response (h=5%)
BSLJ(SoilType2)
NSEW
UD

400

-1000
1000

EW (peak: 523.2 cm/s²)0-10001000

UD (peak: 494.9 cm/s²)0-1000pSv (cm/s)

Acc. (cm/s²)

Acc. (cm/s²)

Ground motion at TK4612（the 2nd event (M7.5))

300

200

100

001020304050
Time (s)2023/02/06 10:24:50 at 4612: Kahramanmaras_Elbistan_Turkiye, Intensity: 6.2

600246Period (s)810BRI Confidential

Sa−Sd curve and response periods
Sa(cm/s/s)
2200

colored line: Turkey Earthquakes(Equivalent damping factor＝15％)

Base shear coefficient CB＊(＊effective mass conversion)
2.2

T=1.0sec.
2000

2Tsukidate (2011Tohoku)

T=1.5sec.

1800

1.8

JMA Kobe (1995Kobe)
Mashiki (2016Kumamoto)

1600

1.6

TK3138_NS
1400

T=2.0sec.

1.4

TK3123_EW

1200

1.2

TK3123_NS
1000

Chokubetsu (2003Tokachi-Oki) Takatori (1995Kobe)

1TK3139_NS

800

0.8

Kashiwazaki (2007Niigata Chuetsu-Oki)

600

TK3139_EW

TK3138_EW

TK4612_NS

400

TK4612_EW
200

0.60.4

BSLJ(Soil Type3)(considering Fh)
BSLJ(Soil Type2)(considering Fh)
BSLJ(Soil Type1)(considering Fh)

002040600.2080

100120140

Sd＊(cm)(＊relative displacement)Response acceleration spectrum Sa and response periods BRI Confidential
Sa(cm/s/s)
2200

T=1.0sec.
Tsukidate (2011Tohoku)

TK3138_NS

2000

1800

T=1.5sec.

T=2.0sec. (Equivalent damping factor＝15％)
colored line: Turkey Earthquakes

Chokubetsu (2003Tokachi-Oki)
JMA Kobe (1995Kobe)

1600

Mashiki (2016Kumamoto)
1400

TK3123_EW

1200

TK3138_EW
TK3123_NS

Takatori (1995Kobe)

TK3139_NS

1000

TK3139_EW

Kashiwazaki (2007Niigata Chuetsu-Oki)

800

600

400

BSLJ(Soil Type3)(considering Fh)
BSLJ(Soil Type2)(considering Fh)
BSLJ(Soil Type1)(considering Fh)

TK4612_EW
TK4612_NS

200

000.5

1

1.5

2

2.5

3T(sec.)Response displacement spectrum Sd and response periods BRI ConfidentialSd(cm)T=1.0sec.
140(Equivalent damping factor＝15％)

T=1.5sec.

TK3139_NS

T=2.0sec.

colored line: Turkey Earthquakes
120

Kashiwazaki (2007Niigata Chuetsu-Oki)

TK4612_NS

TK3138_EW

100

TK3123_NS
Takatori (1995Kobe)
80

TK3139_EW
BSLJ(Soil Type3)(considering Fh)

60

Chokubetsu (2003Tokachi-Oki)

Mashiki (2016Kumamoto)

TK3123_EW
BSLJ(Soil Type2)(considering Fh)

40

BSLJ(Soil Type1)(considering Fh)

JMA Kobe (1995Kobe)

TK4612_EW

20

TK3138_NS

Tsukidate (2011Tohoku)

000.5

1

1.5

2

2.5

3

T(sec.)

Summary

BRI Confidential- The North-South (NS) components of the strong ground motions observed at Hatay/Antakya(TK3123), Hatay/Hassa (TK3138), and Hatay/Kırıkhan (TK3139) have large amplitudes in the SaSd when compared to strong ground motions observed in the recent earthquakes occurred inJapan.
- From the Sa-Sd curve assuming a 15% equivalent damping ratio, the relative displacement
due to the strong ground motion observed at Hatay/Antakya (TK3123) reaches 80 cm even if
the base shear coefficient for buildings (CB) is 0.8.

Acknowledgement:
We used strong motion data provided by AFAD, NIED(K-NET, KiK-net), JMA, and, RTRI.