Addressing Challenging Problems in Unsaturated Soil Mechanics

解决非饱和土力学中的挑战性问题

• 批准号: 3787-2013
• 负责人: Fredlund, Delwyn
• 金额: $ 1.89万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=544144
• 关键词: Addressing; Challenging; Problems; Unsaturated; Soil

The performance of many engineering projects is influenced by the water balance at ground surface. Water balance is strongly influced by climatic conditions (e.g., precipitation, temperature, etc.), as well as the soil conditions near to ground surface. Water is either moving upward from the ground surface by evapo-transpiration or moving into the ground surface through infiltration. It is the calculation of "actual evaporation", AE, from the ground surface that has proven to be the most challenging component to calculate. Actual evaporation rates have been shown to be affected by a number of factors (e.g., ground surface color, salts in the pore-water, salt accummulation at surface and the unsaturated soil properties). This proposal is directed at improving existing models that are used for the calculation of actual evaporation fluxes. The immediate problems being addressed are related to the drying of Oil Sands tailings; however, the proposed analytical advances are applicable to a wide range of soils in dry regions. Another aspect of the proposal research will develop estimation procedures for unsaturated soil property functions for soils that undergo large volume changes as soil suction is increased. The proposed research program is directed towards solving geotechnical engineering problems that have become apparent to engineers attempting to make use of existing evaporation models. Climate data from weather stations is used as input to the prposed soil-atmoshperic model used for water balance simulations.

许多工程项目的性能受到地表水平衡的影响。水平衡受到气候条件（例如降水、温度等）以及靠近地表的土壤条件的强烈影响。水要么通过蒸发蒸腾从地表向上移动，要么通过渗透进入地表。事实证明，计算地表的“实际蒸发量”AE 是最具挑战性的部分。实际蒸发率已被证明受到许多因素的影响（例如地表颜色、孔隙水中的盐分、地表盐分积累和不饱和土壤特性）。该提案旨在改进用于计算实际蒸发通量的现有模型。当前要解决的问题与油砂尾矿的干燥有关；然而，拟议的分析进展适用于干旱地区的各种土壤。该提案研究的另一个方面将开发针对随着土壤吸力增加而经历较大体积变化的土壤的非饱和土壤特性函数的估计程序。拟议的研究计划旨在解决试图利用现有蒸发模型的工程师所面临的岩土工程问题。来自气象站的气候数据被用作拟议的用于水平衡模拟的土壤-大气模型的输入。