非饱和渗流随机模型中水力要素的随机特性研究

为了分析非饱和渗流水力要素的随机特性,将土壤的水力特性参数作为随机空间函数,运用Karhunen-Loeve展开和摄动方法,对二维非饱和渗流进行随机数值模拟。研究结果表明:土壤越干燥,负压水头和含水率的变异性越大;Gardner-Russo模型中的m值越小,含水率的变异性越大;负压水头、含水率及达西流速的变异性对土壤质地的粗糙程度比较敏感;土壤介质的各向异性降低垂向达西流速的变异性。非饱和渗流的随机理论尚待进一步的研究和完善。

Study on random properties of hydraulic factors in stochastic model of unsaturated flows

In order to analyze the random properties of hydraulic factors of unsaturated seepage, hydraulic properties of soils were treated as random space functions, and stochastic numerical simulation for two-dimensional unsaturated seepage has been conducted by the combination of Karhunen-Loeve expansion and perturbation method. It was shown that the variabilities of water head and water content increased with the dryness of soils. The smaller the unsaturated parameter m in the Gardner-Russo model, the larger the variability of water content. The variabilities of water head, water content and Darcian flux were sensitive to the coarseness of soil texture. Anisotropy of soil properties decreased the variability of the vertical Darcian flux. Researches on stochastic theory of unsaturated seepage should be strengthened.