摘要
基于渗流理论、弹性理论及VG土-水特征曲线模型,建立了二维非饱和土渗流-变形耦合控制方程组。该控制方程突破了饱和时渗透系数是常数的局限,适用于任意初始条件和降雨条件的土坡稳定性分析。有限元软件COMSOL Multiphysics能根据已建好的非饱和土坡渗流-变形耦合模型开展分析。通过算例分析了非饱和土降雨入渗过程中渗流-变形的耦合效应,并探讨了考虑饱和渗透系数为变量情况以及不同的初始条件对渗流场和应力场的影响。结果表明:在非饱和土坡降雨入渗过程中渗流-变形的耦合效应是非常显著的,且与时间有关。对于湿陷性土,考虑耦合效应的压力水头变化总是慢于非耦合情况。饱和状态时渗透系数是应变的函数,其值的变化对非饱和土边坡渗流场有一定的影响,但对非饱和土边坡变形影响微弱。初始条件对渗流和变形的影响是非常大的。
Based on the seepage theory,elastic theory and the soil-water characteristic curve from VG,the two-dimensional hydro-mechanical mod-el in unsaturated medium was established. The model could consider not only the variation of the coefficient of permeability at saturation,but also any initial conditions and rainfall boundaries. The finite element software COMSOL Multiphysics could analyze the unsaturated coupled seepage-de-formation equations that had been established. The coupling effect of the model was analyzed through cases. And the influence of the situation that the coefficient of permeability at saturation was changed and different initial conditions to the seepage field and stress field were studied. The results show that:the coupling effect is very significant in unsaturated soil slope during rainfall infiltration and is time related. To the collapsible soil,the changing of pressure head of coupled conditions is always slower than the uncoupled conditions. The coefficient of permeability at saturation is not constant and changing with the soil strain,which has an effect on rainfall infiltration but has weak influence to the deformation. Different initial conditions also have an obvious impact.
出处
《人民黄河》
CAS
北大核心
2014年第9期105-108,共4页
Yellow River
基金
国家自然科学基金资助项目(41172280
41272005)
四川省杰出青年学术技术带头人计划项目(2012JQ0007)
四川省教育创新团队项目
关键词
非饱和土边坡
渗流-变形耦合
降雨入渗
数值分析
unsaturated soil slope
coupled seepage and deformation
rainfall infiltration
numerical analysis
