EFFECTS OF BI-MODAL CHARACTERISTICS OF FRACTURED SOIL PORE ON SEEPAGE FIELD OF UNSATURATED SOIL SLOPE
DOU Hongqiang1，2，HAN Tongchun1，GONG Xiaonan1
(1. Research Center of Coastal and Urban Geotechnical Engineering，Zhejiang University，Hangzhou，Zhejiang 310058，China；2. College of Environment and Resources，Fuzhou University，Fuzhou，Fujian 350116，China)
Abstract：Based on equivalent continuum media model，the fractured soil located on the slope surface can be regarded as dual-porosity media，including the crack network and the pores of soil matrix，and the degree of fissure and the average fissure width as the introducing variables were taken. According to the capillary theory and the pore-size distribution，an effective method was summarized which can evaluate equivalent bi-modal unsaturated soil property functions for fractured soil. Then this method was applied to analyze an engineering practice on how the crack network affects the seepage field under rainfall infiltration condition. The results show that the crack network provides a priority channel for rainfall infiltration，and the perched water table is formed within the slope typically 1–2 m deep.
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2015, Vol. 34 
