Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

NIST Earthquake Engineering Group Members Conduct a Preliminary Earthquake Reconnaissance Mission to Turkey

Following the February 6, 2023 Kahramanmaraş Earthquake Sequence

Recon Turkey
Credit: NIST

In the early morning hours of February 6, 2023, a MW 7.8 earthquake occurred in Turkey, followed by four additional earthquakes throughout the day with MW of 5.8 and greater, including a MW 7.7. The official death toll stands at greater than 53,000 people. A large number of structures collapsed, including many multi-story reinforced concrete buildings.

At the end of March 2023 two members of the Earthquake Engineering Group, Matthew Speicher and Amin Hariri, joined an American Concrete Institute (ACI) 133 team to collect data from the February 6, 2023 Kahramanmaraş Earthquake Sequence.  The focus of the ACI 133 team was to collect building column and shear wall indices to validate a simplified vulnerability criteria first proposed by Ahmad Hassan and Mete Sozen (Hassan 1997). Data was collected from over 250 buildings in more than 10 different cities up and down the fault line.  Additionally, NIST researchers collected supplemental data on the functional recovery of over 50 buildings, mainly focused on schools and hospitals.

Low Rise Vulnerability Assessment
Hassan and Sozen, “Seismic Vulnerability Assessment of Low-Rise Buildings in Regions with Infrequent Earthquakes,”  ACI Structural Journal, Vol 94, No. 1, January-February 1997
Credit: NIST
Released August 31, 2023, Updated November 6, 2023