Present state and perspective of design methods of reinforced soil structures

The soil-reinforcing construction method has a history of over 30 years. The recent 10 years or so have seen great progress in researches and in the application of the method to soil structures in the field. Besides, various design and construction manuals have been made available, generalizing the method. The reinforcing mechanism in such soil structures, including that many such structures demonstrated their capability of withstanding severe ground motions in recent great earthquakes, has not yet elucidated entirely, and still a number of problems await solutions. Under the circumstances, the working group of Design Method, one of the working groups of Japanese Supporting Committee of the Asian Technical Committee for Earth Reinforcement, compiled this paper mainly based on cases of reinforced soil structures in Japan to report the current situation and perspective of design methods, in particular, of geosynthetic-reinforced soil structures and soil nailing.