尖点突变模型在湿陷性黄土微结构失稳中的应用

Application of cusp catastrophe model in microstructural in stability of wet collapsible loess

根据湿陷性黄土的特点,从稳定性角度出发,分析黄土湿陷的多种湿陷机理.对已建立的湿陷性黄土结构失稳突变模型给出一个完整的尖点突变模型的计算过程.利用突变理论揭示湿陷性黄土发生湿陷的变形机制和规律.通过尖点突变模型的计算推导得出:当应力满足突变模型分叉点集方程时,其相对应孔隙的微结构将发生失稳坍塌.此外,由于突变模型的控制变量随着k(含水量ω的函数)值的增大而减小,说明土体浸水湿化是土体发生湿陷的重要影响因素.

According to the characteristics of wet-collapsible loess, its multiple wet-collapse mechanism was analyzed in terms of stability. A complete calculational method with cusp catastrophic model was giv- en for the available catastrophic model of structural instability of wet-collapsible loess. The catastrophic theory was used to reveal the deformation mechanism and pattern of such loess. It was found by evaluation with the cusp catastrophic that microstructural instable collapse of the corresponding pore would take place when the stress satisfied the equation of branchpoint set of the catastrophic model. In addition, the control parameters of the catastrophic model would decrease with the value of k （being of function of moisture ω）, illustrating that the soak-wetting of the soil was an important factor of occurrence of its wet-collapse.