Roadbed settlement deformation after construction in permafrost regions of high altitude(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2017年01期
- Page:
- 43-49
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Roadbed settlement deformation after construction in permafrost regions of high altitude
- Author(s):
- WANG Rui; CHENG Pei-feng; HAN Chun-peng
- School of Civil Engineering, Northeast Forestry University, Harbin 150040, Heilongjiang, China
- Keywords:
- road engineering; high altitude; permafrost; constructed roadbed; settlement
- PACS:
- U416.168
- DOI:
- -
- Abstract:
- To master characteristics of the roadbed settlement deformation after construction in the permafrost regions of Greater Khingan Mountains, this paper selected the typical roadbed section of China to Russia crude oil pipeline great line, used layered settlement instrument as settlement monitoring equipment to observe the change of roadbed settlement through the change of the position of magnetic ring on settlement tube. Taking DS18B20 temperature sensor as temperature acquisition unit, this paper set temperature monitoring system to monitor temperature changes of permafrost, and combined with laboratory test to study permafrost geothermal change and its change rule, and the subgrade settlement deformation. The results show that during the two years after the completion of the project, the ground temperature rising, permafrost degradation and the permafrost moving down that brought by the roadbed soil caused the natural seasonal melted layer compression and permafrost melted compression, which are the main causes of roadbed settlement deformation. Settlement caused by permafrost melted compression is the largest, about 50%. From August to November, melting permafrost layer compressed makes roadbed settlement deformation obvious. In December, as seasonal freezing and the permafrost move up stably, embankment settlement begins to slow. Roadbed thawing settlement development has a certain slope tropism. In a freezing and thawing cycle period, permafrost melting time under roadbed of shade slope is about 30 d less than permafrost melting time under roadbed of sunny slope, and embankment settlement of the sunny slope is greater than embankment settlement of the shade slope. In the same conditions, the high ice content permafrost is greater than that of lower. Permafrost melted compression deformation of embankments whose filling height is above 3 meters increases with the increase of the filling height. The research results can provide theoretical reference for road construction and analysis of roadbed settlement deformation in permafrost regions of Greater Khingan Mountains.
Last Update: 2017-01-21