There are enormous number of road attachment facilities on road network. It is important to prevent accidents due to collapse of those facilities. However, design method to prevent that accidents is not adopted in Japan. To establish the design method, evaluation method for time-variant risk for the collapse is essential. This paper proposes evaluation method for time-variant risk for the collapse of road attachment facilities, especially focusing on structural redundancy and deterioration. In addition, this paper verifies availability of the evaluation method through some trial of analysis and caluculation.
