Owing to difficulties in an implementation of an evacuation drill under an inundated underground condition, investigations through a numerical simulation will be considered as an effective method for making an evacuation planning. In the inundated underground condition, an evaluation of a hydraulic force acting on each evacuee is an indispensable matter. The drag effect has been only employed as the hydraulic force acting on the evacuees so far, because the hydraulic conditions have been solved by shallow water equations. However, in the inundated underground conditions, fluctuations of hydraulic forces caused by considerable changes in water surface level associated with the motions of the evacuees will have significant effects on the crowd behaviors. In this study, unsteady inundated flow conditions are solved by the accurate particle method based on the MPS method which has a high potential to violent flow simulations, and the solved hydraulic forces acting on evacuees are employed in the DEM-base crowd evacuation simulator. After verifying a validity of the developed DEM-MPS model by comparing with previous experimental results, the numerical simulation for crowd evacuation from inundated underground are performed. The numerical results show the fluctuation of the hydraulic forces have an impact on the crowd behaviors and this will influence an evacuation planning.

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 This paper investigates the relationship between feature and vibration properties during hammer tests of tunnel lining. Hammering tests with specimen simulating tunnel lining was carried out and reveal that decay time tends to be long and an absolute peak is observed at eigen frequency in case of specimen with an inner cavity. Three-dimensional numerical calculation is also carried out and verified by means of comparison with the hammering test results. It was revealed that the existence of inner cavity causes absolute peaks in spectrum and the peak frequency is influenced by its configuration. This paper also propose the method to evaluate the safety factor against falling lining concrete by means of the comparison between shear force acting on the crack surface and its shear strength.

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 Short-time heavy rainfall events have increased in Japan. The rainfall events cause flush floods in urban area and the flooded cars expanded the human damages (Nagasaki in 1982). Therefore, it is very important to investigate the flood-flow charastistics and floating behavior of cars on flooded roads. In this study, three kinds of hydraulic model experiments were conducted using model car (Sedan type). First, we measured the flood-flow velocity in underground parking model (1/64 scale). Then, we recorded the floating behavior of the flooded car. Finally, we measured the time series of the drag force exerted on the model cars (1/64 scale) in unsteady flow by using Force gage. The results revealed that the drag force increases rapidly during an early stage becase of the hydrostatic pressure difference.

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