Impact and GNSS-Based Deformation Analysis of the Earthquake in Türkiye on February 6, 2023: A case study of TAG (Tarsus-Adana

Hakan ASLAN ^1* Hakan KOCAMAN ² Recep Bilal SIKAR ³ İbrahim Can TURAN ¹

• ¹ Sakarya University, Sakarya, Sakarya, Türkiye
• ² Sakarya University of Applied Sciences, Sakarya, Sakarya, Türkiye
• ³ Istanbul University-Cerrahpasa, Istanbul, Türkiye

Transportation structures providing rescue, first aid and emergency services after an earthquake play a key role in providing movement in the affected region. The aim of this study is to evaluate and assess the earthquake performances of the regional transportation networks along with the infrastructures on the Tarsus-Adana-Gaziantep (TAG) motorway passing through Gaziantep Nurdagi district. The investigated motorway is under the authority of the 5 th Regional Directorate of the General Directorate of Highways (KGM). The TAG motorway is the most important transportation artery in the region affected by the earthquake as it provides the connections to airports, state roads and urban transportation networks. Within this concept, viaducts, underpasses, overpasses, road retainers, drainage structures and traffic safety elements in the sections of the TAG motorway were inspected. In addition, this study includes the earthquake impact evaluation of transportation network and traffic characteristics of Kahramanmaras and Hatay provinces. In the case of the city of Hatay, the deformations occurred on the highway providing access to the city airport were specifically considered. Within the scope of this study, transportation structures were examined and photographed on site and their coordinates were determined using the Global Navigation Satellite Systems (GNSS) device. Later, these coordinates were brought together with the earthquake data obtained from the official website of the Ministry of Internal Affairs Disaster and Emergency Management Presidency (AFAD). The collected data was spatially analysed by using geographic information system software. The findings highlight that while the primary transportation infrastructure remained operational, localized damages were observed, including road subsidence, landslides, and expansion joint failures. Notably, steel viaducts exhibited superior seismic performance compared to concrete viaducts, emphasizing the importance of material selection in seismic resilience. The study also revealed that soil-structure interaction and resonance effects contributed to structural deformations, underscoring the need for improved geotechnical assessments in transportation network design. The results provide a valuable resource to develop design and reinforcement methods for transportation structures to perform their functions for future earthquakes.