蒸发蒸腾作用下非饱和土的吸力和变形影响因素分析  

On influence factors of suction and deformation of unsaturated soil under evaporation and transpiration effect

作　　者：陈建斌[1] 孔令伟[1] 赵艳林[2] 吕海波[2] 

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,武汉430071 [2]广西大学土木建筑工程学院防灾减灾研究所

出　　处：《岩土力学》2007年第9期1767-1772,1778,共7页Rock and Soil Mechanics

基　　金：国家重大基础研究前期研究专项(No.2003CCA02200);交通部西部交通建设科技项目(200631878530);中国科学院武汉岩土力学研究所领域前沿基金项目(No.Q110301)

摘　　要：采用热湿耦合非等温流方程,结合实际蒸发和植物蒸腾的边界条件,考虑了水分迁移所引发的非饱和土应力变形行为,从而建立了大气-非饱和土相互作用模型。采用该模型对控制非饱和土吸力和变形的大气蒸发和植物蒸腾等多参数进行了影响程度分析。结果表明,控制地面吸力和变形的主导因素是外部气象条件,尤其太阳净辐射量和风速,土体水力和热力特性参数影响程度有限;在植被覆盖条件下,吸力变化主要取决于植物叶面积指数LAI,而总腾发量的大小决定了地表变形量。Based on the equations of coupled heat-moisture anisothermal flow and the behaviors of stress-strain of unsaturated soil,an interaction model of atmosphere-unsaturated soil is established with the boundaries of actual evaporation and vegetation transpiration.The influence of climatic evaporation and vegetation transpiration on the suction and deformation of soil surface are analyzed by the interaction model.It is shown that the major governing factor for the suction and deformation of soil surface is outer climatic condition where solar net radiation and wind velocity are the most contribution,while the internal hydraulic and thermal parameters of soil property play a less role in the estimation of evaporation.With the cover of vegetation,the behavior of suction depends on the leaf area index（LAI）,while the magnitude of total evaporation and transpiration determines the deformation of soil surface.

关 键 词：非饱和土 大气蒸发 植物蒸腾 吸力 变形 影响因素 

分 类 号：TU411[建筑科学—岩土工程]