堀 英祐; 原 英嗣; 村上 公哉
日本建築学会環境系論文集 86 779 69 - 77 日本建築学会 2021年01月
[査読有り] In this study, it is assumed that those who cannot return home will stay in the underground mall space for about one night at the time of disaster. Therefore, in order to understand the stay environment, we measured the thermal environment without the air-conditioning, and conducted the subject experiment on the actual state of sleep and the change of fatigue assuming night stay in the thermal environment. The obtained findings are shown below.
1) During the daytime in summer, air conditioning was controlled at around 27 °C. During non-air conditioning at night, the temperature was almost the same as the outside air temperature. It was confirmed that the average temperature at night increased by 0.65 to 1.79 °C compared to the daytime. In intermediate season, there was no air conditioning throughout the day and night, but there was no significant temperature change at around 20 °C. During the daytime in winter, when the outside air temperature was hovering around 5 to 7°C, the temperature was hovering around 15 to 18°C, except for the area around the entrance/exit stairs. On the other hand, the temperature at measurement point 2 was only 7 to 9 °C even under air-conditioned conditions, indicating that there was a large temperature difference even within the underground mall.
2) From the results of wind velocity measurements, the underground mall space closed with shutters with gaps is significantly lower than the surrounding wind velocity above the ground. It had dropped to 34.2 % in intermediate season and 11.5% in winter. However, it was confirmed that there was a time period when the wind velocity was high enough to feel the airflow physically, and it was confirmed that the influence of the airflow on the thermal sensation could not be ignored.
3) According to the PMV evaluation during the sleep experiment, the average PMV in summer was 0.75 in the sleeping state and 1.34 in the sitting state, indicating that it was slightly warm even when it was at rest. In intermediate season, the patient was in a comfortable state with a sleep state of 0.01 and a sitting position of 0.75. In winter, it was -1.72 in the sleeping state and -0.39 in the sitting position, so it was confirmed that the sleeping state was cold.
4) As a result of studying sleep quality and fatigue recovery status, the Sleep onset latency is short and the Latency to persistent sleep is long in summer. On the other hand, in winter, it is difficult to fall asleep deeply, the Wake episodes are long and the number of times of Long wake episodes are high, so when the person goes into sleep and the metabolism falls, the person wakes up immediately because he feels cold. Regarding fatigue recovery, the correlation with the longest sleep episode was the highest, with a correlation coefficient of 0.52, but there was no significant difference between the seasons.
5) Based on the measured results, it was shown that the measures to reduce the feeling of warm and cold during temporary stay in summer and winter were to add airflow of 0.6 m/s or more with a fan or other device in summer and to maintain a temperature of 20°C or more with a portable heater or other device in winter.