Project Title:  Project for Determination of Design, Analysis, and Construction Principles for Seismic Retrofit Methods
Funding Agency: Republic of Türkiye, Ministry of Environment, Urbanization and Climate Change
Project Coordinator: Prof. Dr. Alper Ilki (ITU)
Project Topic: Türkiye is under high seismic hazard due to its location on active tectonic belts, and a significant portion of the existing building stock is far from meeting modern design and construction standards. In particular, reinforced concrete, steel, and timber structures that have not received engineering services or do not possess the ductility and strength capacity foreseen by the codes of their design year pose a great risk of loss of life and property in a potential earthquake. Although the Turkish Building Earthquake Code (TBDY-2018), which constitutes the current legal framework, is comprehensive, it generally mandates “new building performance” for the retrofitting of existing buildings. This requirement restricts the widespread use of retrofit applications due to technical difficulties and high costs. Furthermore, despite rapid developments in structural technology, design and application principles for innovative technologies such as fiber-reinforced polymers, damping systems, seismic isolation, and external retrofitting are not comprehensively included in the national legislation. This project, carried out with the support of the Republic of Türkiye Ministry of Environment, Urbanization and Climate Change and under the coordination of Istanbul Technical University, and involving 20 expert researchers from 11 different universities across the country, concerns the preparation of a standalone “Turkish Building Seismic Retrofit Code” that responds to Türkiye's unique needs. The project aims to provide cost-effective and applicable solutions without compromising safety. In this context, new intermediate earthquake ground motion levels refining seismic hazard analysis have been defined, and optimized minimum performance objectives based on building use classes have been developed. The project addresses a wide typology covering cast-in-place reinforced concrete, steel, timber, and tall buildings, as well as moderately damaged public buildings. Within the scope of the work, alongside traditional methods such as RC jacketing, design rules and detailing principles based on advanced engineering fundamentals and compatible with international standards have been established for external retrofit methods applicable while the building remains in use, energy damping systems, and fiber-reinforced polymer applications. Consequently, this project aims to make retrofitting a priority option and increase Türkiye's seismic resilience by establishing a sustainable legislative infrastructure with a strong theoretical background that aligns with field application realities.