A non-sprinkling snow-melting pavement has generally adopted groundwater heat, ground heat, heated warm water, etc. as heat sources. The temperature level of the heat source is around 10-15°C except heated warm water and is by no means high. Therefore, we have to better understand the heat transfer between a heat injection pipe and the surrounding pavement. This is indispensable to economical and reliable design of the non-sprinkling snow-melting pavement.
A theoretical model is proposed to evaluate the snow-melting performance of the pavements with folded serpentine piping configurations. The pavement heat exchanger is modeled as a straight panel incorporating both a going and return pipes can be treated as line heat sources to be added to the equation for vertical heat flow in the pavement. This results in a system of one-dimensional equations that is rapid for design calculations.
The accuracy of the numerical model is shown from the comparison of the fluid temperature distributions along the heat injection pipe and of the vertical temperature profile in the pavement at three different experimental sites. The model could also lead the overall heat transfer coefficients between the fluid in the heat injection pipe and the surrounding pavement.

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It was written with "Elementary school building is made to be 2-floor and the pupil waiting room is placed at first floor because the snow cover is frequent" in archives of the Nagano Prefectural office. So by examining the drawings of the elementary school building that had put in archives of the Nagano prefectural office, next fact was proven. It was observed throughout the Meiji period that the installation rate of the elementary school building with pupil waiting room increased in proportion to the snow cover. So it was indicated to become an effective index, when the elementary school in snowy area was examined. It was clarified that the elementary school building that it put pupil waiting room at first floor and placed the classroom only over the second floor was the school building that was peculiar in the snowy region. It is future problem to compare with the other prefecture, because it seems to be uncertainly that it is judged only in Nagano Prefecture, since there is small proportion occupied for the whole.

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In snowy areas, a lot of roads are closed due to heavy snowfall in every winter season. Some roads may be located on important routes for social and economic activities during non-snow seasons in these roads. Therefore, it is necessary to establish the rational improvement method of road networks to ensure the regional traffic in these areas. In this paper, the author proposed the practical method on priority level for the improvement planning of the winter road network taking the possibility of using roundabout into consideration. Furthermore, the author applied this method to data on road traffic closure in the Tohoku District and examined the efficiency of the system.

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