Abstract
In Japan, the construction of social infrastructure has been increasing since the high eco-nomic growth in the 1960s. Right now it is a problem in Japan that these infrastructures are deteriorat-ing. It is expected that further deterioration will occur in the future so the maintenance and operation for these infrastructures is now a signifi-cant subject.Under these circumstances, a managing method named as an infrastructure asset management is beginning to be employed recently. Infrastructure asset management is a strategic management of physical assets during their life in the organization, which enables us to manage physical assets effectively and efficiently. The goal is to conduct a mid and long term efficient maintenance and operation plan for the subway tunnels and to decide the proper budget for rehabilitation.
