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Title: Thermal–moisture dynamics of embankments with asphalt pavement in permafrost regions of central Tibetan Plateau

Abstract

Subsurface moisture content is one of the critical factors that control the thermal dynamics of embankments. However, information on the subsurface moisture movement and distribution in embankments is still limited. To better understand the coupled water and heat transport within embankments, subsurface temperature and moisture of an asphalt pavement highway were extensively measured from 2009 to 2011. Collected data indicate that pure heat conduction is the overall main mechanism of heat transport in the embankment and heat convection plays a relatively unimportant role in heat transport. The results also indicate that subsurface moisture and temperature dynamics in the asphalt layer is strongly related to the rainfall events, while the subsurface moisture content below the road base course maintains relatively constant. Rainfall in summer leads to rapid cooling of the subsurface soil. Our results suggest that frequent and small rainfall events favour the thermal stability of the embankment due to the loss of latent heat of water evaporation. Moisture migration during freezing still occurred in the gravel fill and the water infiltrated into the active layer during thawing period. Freezing-induced water migration may result in the increase in water content of the embankment and the decrease in compactness of gravel fill.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
Chinese Academy of Sciences (CAS) - State Key Laboratory of Frozen Soil Engineering; National Key Basic Research Program of China; National Natural Science Foundation of China (NNSFC)
OSTI Identifier:
1390823
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: European Journal of Environmental and Civil Engineering; Journal Volume: 19; Journal Issue: 4
Country of Publication:
United States
Language:
English
Subject:
Qinghai-Tibetan Plateau; asphalt pavement; permafrost; rainfall; soil moisture content; soil temperature

Citation Formats

Wen, Zhi, Zhang, Mingli, Ma, Wei, Wu, Qingbai, Niu, Fujun, Yu, Qihao, Fan, Zhaosheng, and Sun, Zhizhong. Thermal–moisture dynamics of embankments with asphalt pavement in permafrost regions of central Tibetan Plateau. United States: N. p., 2014. Web. doi:10.1080/19648189.2014.945043.
Wen, Zhi, Zhang, Mingli, Ma, Wei, Wu, Qingbai, Niu, Fujun, Yu, Qihao, Fan, Zhaosheng, & Sun, Zhizhong. Thermal–moisture dynamics of embankments with asphalt pavement in permafrost regions of central Tibetan Plateau. United States. doi:10.1080/19648189.2014.945043.
Wen, Zhi, Zhang, Mingli, Ma, Wei, Wu, Qingbai, Niu, Fujun, Yu, Qihao, Fan, Zhaosheng, and Sun, Zhizhong. Mon . "Thermal–moisture dynamics of embankments with asphalt pavement in permafrost regions of central Tibetan Plateau". United States. doi:10.1080/19648189.2014.945043.
@article{osti_1390823,
title = {Thermal–moisture dynamics of embankments with asphalt pavement in permafrost regions of central Tibetan Plateau},
author = {Wen, Zhi and Zhang, Mingli and Ma, Wei and Wu, Qingbai and Niu, Fujun and Yu, Qihao and Fan, Zhaosheng and Sun, Zhizhong},
abstractNote = {Subsurface moisture content is one of the critical factors that control the thermal dynamics of embankments. However, information on the subsurface moisture movement and distribution in embankments is still limited. To better understand the coupled water and heat transport within embankments, subsurface temperature and moisture of an asphalt pavement highway were extensively measured from 2009 to 2011. Collected data indicate that pure heat conduction is the overall main mechanism of heat transport in the embankment and heat convection plays a relatively unimportant role in heat transport. The results also indicate that subsurface moisture and temperature dynamics in the asphalt layer is strongly related to the rainfall events, while the subsurface moisture content below the road base course maintains relatively constant. Rainfall in summer leads to rapid cooling of the subsurface soil. Our results suggest that frequent and small rainfall events favour the thermal stability of the embankment due to the loss of latent heat of water evaporation. Moisture migration during freezing still occurred in the gravel fill and the water infiltrated into the active layer during thawing period. Freezing-induced water migration may result in the increase in water content of the embankment and the decrease in compactness of gravel fill.},
doi = {10.1080/19648189.2014.945043},
journal = {European Journal of Environmental and Civil Engineering},
number = 4,
volume = 19,
place = {United States},
year = {Mon Sep 01 00:00:00 EDT 2014},
month = {Mon Sep 01 00:00:00 EDT 2014}
}
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