变形对非饱和土渗透系数影响规律模拟研究

对有、无缝合复合材料层合板的拉伸疲劳性能进行了试验研究，考察了0^\circ 缝合对复合材料光滑板拉伸疲劳损伤扩展规律的影响. 通过有限元素法分析了有、无缝合复 合材料层合板的应力状态分布情况，对缝合复合材料层合板的拉伸疲劳损伤及其扩展机理进 行了分析. 研究表明，缝合改变了复合材料层合板拉伸疲劳损伤起始与扩展的机理，针脚 附近的面内正应力\sigma_{x}与层间剪应力的集中对层合板拉伸疲劳损伤的 发生与扩展有着重要的作用，自由边界处的层间集中应力对缝合板的疲劳性能也有影响. 自 由边界处的层间集中应力是导致无缝合层合板疲劳损伤及其扩展的主要原因.

PROBABILITY BASED MODEL FOR INFLUENCE OF DEFORMATION ON HYDRAULIC CONDUCTIVITY FUNCTION OF UNSATURATED SOILS

The hydraulic conductivity function is the key parameter in the seepage analysis of unsaturated soil. Based on the foundational equation of fluid mechanics and the theory of probability and statistics,this paper proposes a theoretical model for saturated permeability function. This model can take the influence of soil structure into account. It is combined with the Mualeum(1976)relative permeability function model,together with the variation law of the structural parameters during deformation proposed by Assouline(2006). The influence of deformation on unsaturated permeability function is modeled. The paper compares the experimental results and some available models and the present model. The present model can improve the prediction precision without any increase of experimental workload. The necessities of applying statistic theory into soil mechanics is also discussed in the end of the paper.