Membranes have high transmissivity within the visible-light range and are used in buildings to create a bright interior space. In regions with heavy snowfall, various means are used to remove snow from the roof of membrane structures in order to maintain a bright interior space during winter. However, the current evaluation of snow load on the roof of membrane structures is the same as that used for buildings from which snow removal is not frequently carried out. This is thought to be due to the current small number of membrane structures in regions with heavy snowfall and to insufficient clarification of the effectiveness of methods for removing snow from roofs. In this study, we conducted interviews with building managers as well as on-site surveys with regards to snow accumulation on the roof of membrane structures for the purpose of collecting data that may be used as a basis for appropriate evaluation of snow load on the roof of membrane structures in regions with heavy snowfall. Furthermore, from the survey results, we estimated the most effective roof design for snow removal, and, using this roof design, we performed membrane structure analysis that took into account snow load on the roof. The results showed that for a membrane structure, a V-shaped roof of membrane panels is effective for reducing snow load on the roof.

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Under snowfall condition in winter season, vehicular traffic is affected in Fukui metropolitan area. Vehicles are the principal means of transportation in this area, so it is very important to keep traffic flow unhindered as much as possible.
This paper presents the benefit of expressway on traffic under snowfall condition in easing traffic congestion and retaining the level of accessibility in Fukui Metro-politan area as an example.
To evaluate the benefit of expressway on traffic, an traffic assignment simulation model considering the relationship of snowfall depth to traffic capacity and velocity is proposed. By making use of this model, it is possible to simulate more practical traffic situation under various snowfall condition.
It is concluded that expressway is more effective in heavy snowfall area to ease traffic congestion and improve accessibility among cities in Fukui Metropolitan area.

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When a photovoltaic (PV) array is installed at a roof, the snow on the array and the roof needs to be removed not only to reduce the snow load but also to effectively utilize the solar system. If dc current is flowed through each PV module from a power supply, the surface of it was surely heated, to assist snow sliding on the array. In the electrically heating system, snow sliding at the array needs to be detected to turn the system off and to generate the electric power by the solar system. In the preliminary tests for snow sliding, the instance of snow sliding on the PV array which consists of ten PV panels was identified by the VTR pictures taken every one minute during the tests. To find out the event of snow sliding over the PV panel, the time variation of temperature at the under surface of the PV panel measured at intervals of ten minutes was investigated in detail. It was revealed that the temperature at the under surface of the array always rose above 3°C at least whenever snow slid at the PV panel.

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