摘要
浸润线的高低对堰塞体的渗透稳定至关重要,而堰塞体材料渗透系数往往具有很强的随机性,如果采用确定性模型则不能准确地模拟实际的渗流场及浸润线位置。本文利用Monte Carlo方法在堰塞体材料渗透系数满足对数正态分布的条件下,对唐家山堰塞体渗流场进行了300次二维随机模拟。结果表明,受材料随机性的影响,水头场、浸润线分布及渗透坡降场等均呈现随机特性,但和渗透系数场的随机性并非简单的线性关系,水头方差空间变化特性较为明显,越往下游其值越大;对比确定性模型,随机性模型中出逸点的计算结果更具统计意义,对工程防护中有一定指导意义;由于受边界条件影响较小,堰体中间部位渗流特性基本满足正态分布;浸润线逸出点处受边界条件影响较大,逸出位置分布集中,不服从正态分布,其余部位浸润线位置高程随机过程基本服从正态分布。
The height of the saturation line is crucial to the seepage stability of barrier dam, while the permeability coefficients of barrier dam material have strong randomness, then the deterministic model cannot simulate the actual seepage field and the saturation line site accurately. Under the condition of the permeability coefficient of barrier dam material meeting the logarithmic normal distribution, the Monte Carlo method is used for the twodimensional stochastic simulation for the seepage field of Tangjiashan barrier dam, with 300 times simulation. The results demonstrate that the head field, saturation line distribution and seepage gradient field are present the randomness because of the influence of the material randomness, but this randomness has not the simple linear relation with the randomness of the permeability coefficient field, the spatial variation characteristics of head variance is more obvious, the farther the downstream is, the more the values increase. Comparing the certainty model, the calculation results of the escape point in the stochastic model have more statistical meanings, which has the certain guiding significance for the Engineering protection. The seepage characteristics of the middle part of the barrier dam basically meet the normal distribution due to the smaller influence of boundary conditions. The influence of boundary conditions on the escape point of the saturation line are great, the escape location distribution is concentrated and cannot obey the normal distribution, the random process of the elevation location of the saturation line for the other parts of barrier dam basically follows the normal distribution.
出处
《东北水利水电》
2016年第4期43-47,72,共5页
Water Resources & Hydropower of Northeast China
基金
国家自然科学青年基金(51209154)
