基于蒙特卡罗模拟的混凝土坝渗流性态区间综合评价

针对混凝土坝渗流性态评价过程中专家单值打分主观性较强等问题,采用区间评分的形式,引入权重因子表征专家评价水平差异,利用区间概率分布函数描述专家意见分歧程度,提出了基于区间宽度的主观权重修正方法,在此基础上利用蒙特卡罗模拟法进行渗流性态综合评价。采用该方法对某混凝土坝7号坝段的渗流性态进行了综合评价,评价等级隶属于基本正常及以上的概率为99.9%,评价结果为基本正常,与实际运行情况相符,表明基于蒙特卡罗模拟的区间评价法应用于混凝土坝渗流性态评价是可行的,可用于不确定性高、单值赋分难度大的工程评价。

Comprehensive interval assessment of seepage behavior for concrete dams based on Monte Carlo simulation

Aiming at reducing the strong subjectivity caused by single value scores in seepage behavior assessment of concrete dams, the methods based on interval grading are suggested. The weight factors are introduced to represent the difference among evaluation levels of the experts. The degree of the disagreement on seepage behavior is described by an interval probability distribution function and the subjective weight is corrected based on the interval width. The Monte Carlo simulation method is then introduced into the comprehensive evaluation of the seepage behavior. The proposed method was applied to assess the seepage condition of the No. 7 section in a concrete dam and the probability of the assessment grade belonged to basic normal and above normal was 99.9%. The assessment result is basically normal and consistent with actual operation, showing the interval assessment method based on Monte Carlo simulation is feasible to evaluate the seepage behavior of concrete dams and it can also be applied to project assessment with high uncertainty in which single value grading is difficult to be applied.