Because road tunnel inspection manual was revised in June, 2014, the periodic inspection once in five years was required. There are many road tunnels of 11,000 in Japan, development of inspection technology, and securing of talented person becomes important. As an inspection robot technology, MIMM (Mobile Imaging Technology System & Mobile Mapping System) attracts attention now. In this research, we weighed MIMM measurement result against a proximity viewing result in a real tunnel and carried out the quality inspection of the crack.

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 Methods of constructing tunnels using the minimum quantities of cement-type support materials for high-level radioactive waste disposal facilities have been developed. Research and development concerning the technical aspects of the formation of rock segments using low alkaline mortar have been conducted. This study examined the mechanical characteristics of rock segments and backfill materials and analyzed the stability of the drift that is supported by the rock segments and gravel backfill. The results confirmed the technical aspects of the formation of the rock segments and the effectiveness of the planned efforts to further reduce the amount of cement used.

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 As road tunnels are long and enclosed spaces, there exists a threat that a large number of victims could be generated caused by thermal fume and smoke propagation at the case of a fire. In order to avoid this danger, low-speed ventilation control procedure is adopted in Japan to prevent smoke from propagating inside the tunnel by controlling longitudinal air velocity. In recent years, constructing tunnels with steep inclinations is increasing. In the present paper, the effects of the low-speed ventilation control system in case of inclined tunnels are investigated by fire and evacuation simulations. Our research in this paper shows that longitudinal inclination and stranded vehicles in tunnels deteriorate a situation due to behavior of thermal fume, and that there is a specific range of air velocity for each inclination that minimizes the number of sufferers.

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