The present paper proposed quantitative assessment method for road tunnel fire safety by numerical simulation of evacuation in smoke. To evaluate the influence of smoke on evacuees, Smoke Environment Level (R) has been defined as a function of time and longitudinal location, by simplifying smoke distribution derived from 3-D CFD analysis and then weighting it with visibility. By mapping R on time-distance plane, smoke's behavior in tunnel fire can be concisely expressed. In the developed 1-D evacuation simulation method using R, each evacuee recognized the necessity of evacuation through smoke's behavior, other evacuees' behavior or emergency announcement. The number of people who were surrounded by thick smoke in 10 minutes was used as evaluation index for tunnel fire safety. The present method has been tested in the cases of various longitudinal gradients and evacuees' moving speed.

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 Underground spaces, such as underground mall, subway stations and basements, are prone to inundations caused by pluvial and fluvial flood, storm surge and tsunami. Many Japanese cities are located in low-lying area and have these underground spaces. As devastating inundation damages are anticipated if these spaces would be inundated, safe evacuation planning should be made as soon as possible. In this paper, factors for improving evacuation rate in safety from these spaces are discussed on the basis of simulating behavior of persons in evacuation from a large scale underground shopping mall. From the results, it is found that the safe evacuation rate depends on the rate of congestion and that evacuation into a connecting building is very important to improve the rate of safe evacuation. These results are useful to make an evacuation plan.

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