Design and experiment on a solar heat-supplying tube against frost damage of embankment in cold regions
Hu Tianfei1,2 Wang Tianliang1,2 Liu Jiankun3 Chang Jian3
1. School of Civil Engineering, Shijiazhuang Tiedao University, Shijiazhuang 050043, China; 2. Key Laboratory of Roads and
Railway Engineering Safety Control of Ministry of Education, Shijiazhuang Tiedao University, Shijiazhuang 050043, China;
3. Beijing Jiaotong University, Beijing 100044, China
Abstract：In order to improve the wide-spread frost heave damage of subgrade in seasonally frozen soil regions, a more active thermal measure called solar photothermal technology was introduced. The application idea is to provide an external heat source by the solar photothermal technology, and to adjust the heat input and output of subgrade. Through the above active regulation, the excessive heat loss of subgrade will be controlled, and then the negative temperature and frost heave will be eliminated effectively and timely. The resource and technical conditions of renewable heat sources such as solar energy have good applicability in subgrade engineering. In China, the seasonally frozen soil and solar energy coincide well in geographical distribution. Compared with architectural and industrial applications, solar thermal technology has more advantages in subgrade engineering. Regarding to the differences of photothermal devices and special requirements of subgrade heating, a type of solar heat-supplying apparatus for subgrade was designed and manufactured. Its structure layout is vertical columnar tube, and it mainly consists of the solar heat-collecting section and the subgrade heat-supplying section, the former one adopts glass-metal sealing vacuum tube. These two sections were connected directly by flanges, and act as an integrated heat conversion unit to realize the collection, storage and delivery of solar energy autonomously. Its operation mode is to supply heat for subgrade during the whole year, i.e., to store heat previously in warm season and to compensate heat loss timely in cold season. The performance test show that the heating temperature increases with solar radiation intensity, and can be 10℃ higher than the atmospheric temperature in winter, thus it acts as a favorable “heat source” role. The solar heat-supplying tube belongs to a new type of active thermal technology for subgrade engineering in cold regions.
胡田飞 王天亮 刘建坤 常 键. 面向寒区路基工程的太阳能集热管的设计与试验[J]. 土木工程学报, 2019, 52(S1): 44-52.
Hu Tianfei Wang Tianliang Liu Jiankun Chang Jian. Design and experiment on a solar heat-supplying tube against frost damage of embankment in cold regions. 土木工程学报, 2019, 52(S1): 44-52.
