Calculation of Subgrade Moisture Index in Seasonally Frozen Regions considering Evapotranspiration at Subzero Temperatures and the Pavement Coverage Effect
Calculation of Subgrade Moisture Index in Seasonally Frozen Regions considering Evapotranspiration at Subzero Temperatures and the Pavement Coverage Effect
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考虑零下温度蒸散量和路面覆盖效应的季冻地区路基含水率计算
DOI：
10.1155/2021/6612197
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发表时间：
2021-03
影响因子：
1.8
通讯作者：
Cong Li
中科院分区：
文献类型：
--
作者：
li dongxue;Zongyuan Sun;Jianming Ling;Cong Li
直接位于已铺装公路下方的路基材料的含水率指数通常由未覆盖边坡的含水率指数表示。然而，现有的研究表明，由于蒸散量的原因，裸露的斜坡和覆盖的路基之间存在着显著的水分差异。此外，在太阳辐射、风等因素的影响下，即使在零度以下的温度下，土壤蒸发蒸腾量仍然存在。本文提出了一种改进的季节性冰冻地区路基含水率计算方法。用联合国粮食及农业组织的Penman-Monteith(FAO-56 PM)方法代替传统的Thornthwaite方法来估算零度以下坡面土壤的潜在蒸散量(PE)。根据水分平衡原理，以坡面PE、径流量和水分亏缺为输入参数，计算裸露坡面的水分指数。通过土壤含水率矩阵吸力关系确定的修正系数来确定路面覆盖层对路基湿度的影响，建立了根据相应坡度估算路基材料含水率的优化计算公式。对东北中国典型季节冻土区的计算结果表明，该方法对路基含水率预测具有较好的适用性和准确性。公路坡面裸露土壤在零度以下的潜在蒸散量可达年蒸散量的9.8%~15.7%。季节性冰冻地区的水分指数范围为−14.2-57.3.这些发现将对季节性结冰或面临类似气候条件的地区路基设计和施工的有效改进具有重要意义。
The moisture index of subgrade material directly below a paved highway is typically represented by that of an uncovered slope. However, existing studies have demonstrated the existence of a significant moisture content difference between an uncovered slope and covered subgrade owing to evapotranspiration. Moreover, under the influence of solar radiation, wind, and other factors, soil evapotranspiration persists even at subzero temperatures. This paper presents an improved method for subgrade moisture index calculation for regions that freeze seasonally. Instead of the conventional Thornthwaite method, the Food and Agriculture Organization Penman–Monteith (FAO-56 PM) method was employed to estimate the potential evapotranspiration (PE) of slope soil at subzero temperatures. Based on the moisture balance principle, the PE and water runoff and deficit were used as input parameters to calculate the moisture index of an uncovered slope. After the effect of pavement cover on subgrade humidity was defined through a correction coefficient determined via the matric suction dependence of soil water content, an optimized calculation formula was developed to estimate the moisture index of the subgrade material according to that of the corresponding slope. The results calculated on a typical seasonally frozen region in Northeast China demonstrated the applicability and accuracy of the proposed method for predicting the subgrade moisture. The potential evapotranspiration of an uncovered highway slope soil at subzero temperatures could reach 9.8%–15.7% of the total annual evapotranspiration. The moisture index range for seasonally frozen regions was −14.2–57.3. These findings will have important implications for effective improvements in the design and construction of subgrade in regions that freeze seasonally or face similar climatic conditions.
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DOI：
10.1061/(asce)te.1943-5436.0000840
发表时间：
2016-01
期刊：
Journal of Transportation Engineering-asce
影响因子：
--
作者：
A. Zareie;Md. Shohel Reza Amin;L. Amador-Jimenez
通讯作者：
A. Zareie;Md. Shohel Reza Amin;L. Amador-Jimenez
DOI：
--
发表时间：
1998
期刊：
Acta Botanica Sinica
影响因子：
--
作者：
Sun Cheng
通讯作者：
Sun Cheng
DOI：
--
发表时间：
1996-08
期刊：
Journal of Tongji University
影响因子：
--
作者：
Liu Xiping;S. Lijun
通讯作者：
Liu Xiping;S. Lijun
影响因子：
0.6
作者：
V. Vizaya Bhaskar
通讯作者：
V. Vizaya Bhaskar
DOI：
10.1061/(asce)0733-9410(1990)116:7(1073
发表时间：
1990-07
期刊：
Journal of Geotechnical Engineering
影响因子：
--
作者：
R. G. McKeen;L. Johnson
通讯作者：
R. G. McKeen;L. Johnson