Addressing Challenging Problems in Unsaturated Soil Mechanics

地表水量平衡是影响许多工程项目效益的重要因素。水平衡受到气候条件(如降水、温度等)以及接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流动，要么通过渗透进入地下。事实证明，计算地面的“实际蒸发量”(AE)是最具挑战性的部分。实际蒸发率受到许多因素的影响(例如，地表颜色、孔隙水中的盐分、地表盐分的累积和非饱和土壤的性质)。这项建议旨在改进现有用于计算实际蒸发量的模型。正在解决的迫在眉睫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广泛土壤。该提案研究的另一个方面将开发随着土壤吸力的增加而经历较大体积变化的土壤的非饱和土壤性质函数的估计程序。拟议的研究计划旨在解决岩土工程问题，这些问题对于试图利用现有蒸发模型的工程师来说已经变得显而易见。来自气象站的气候数据被用作提出的土壤-大气模式的输入，该模式用于水平衡模拟。

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.