Abstract
In order to make smoke movement of fire clear in a deep underground parking space, a series of experiments were conducted with the 1/10 scale model of the four stories basement under natural ventilation condition. This model consists of four stories parking spaces of relatively large area compartment and two stairwells having vertical shafts. For understanding the smoke movement and the optical density of the smoke, the concentration of carbon dioxide were measured at many points as a substitute for fire smoke.
As a result, it was found that carbon dioxide gas was distributed over the large parking space of the fire floor by natural convection, and the optical density of the smoke increased all over the parking space with the lapse of time. The smoke was two layered near fire source, which was thicker in upper layer and thinner in lower layer. On the other hand, in the parking rooms apart from the fire source point, the distribution of the optical density were uniform from the ceiling to the floor.
Whereas, the experimental data of carbon dioxide gas concentration were compared between with the prediction by the two layer zone model. The prediction data were larger than the experimental data. But the predictive values normalized by the data near fire source agreed well with the experimental values normalized by that in the parking space, but not in the stairwells.
