State of the art and development tendency of seismic retrofit for reinforced concrete structures in Japan

Reliable techniques for seismic retrofit of existing reinforced concrete structures are essential importante for improving the seismic performance of the buildings and promoting the sustained development of the society.Effective seismic performance evaluation and retrofitting methods for existing reinforced concrete structures have been developed in Japan through many decades of engineering practice and are helpful for improving the seismic retrofitting practice in China.Following a brief introduction to the retrofit design methods of Japan,the conventional retrofitting methods of reinforced concrete structures in Japan and their recent refinement are summarized in detail and the undergoing development in next-generation retrofitting methods are described with focuses on innovative techniques featuring attached external substructures,damage control and self-centering techniques.