基于信息熵-未确知测度理论的膨胀土胀缩分级评价

The classification of the grade of shrink and expansion for the expansive soils based on information entropy and uncertainty measurement theory

将未确知测度理论应用到膨胀土胀缩等级评价中,针对膨胀土中等级评价中许多不确定性影响因素,选用液限、胀缩总率、塑性指数、天然含水率、自由膨胀率等5个评价指标,建立了膨胀土胀缩等级分类评价和排序模型。根据15组膨胀土实测数据,建立各影响因素的未确知函数,对其进行定量分析;并利用熵计算各影响因素的指标权重,依照置信度识别准则进行等级判定,最后得出膨胀土胀缩分级的评价结果。该模型的评价结果与物元可拓评判法评价结果有较好的一致性。该评价方法能解决膨胀土胀缩等级评价中诸多因素不确定性问题,还可以按难易程度进行排序。

Due to the uncertain factors in judging the grade of shrink and expansion of the expansive soils,the classification of the grade of shrink and expansion model of the expansive soils was established based on the uncertainty measurement theory,including five indexes reflecting the shrink and expansion of expansive soil,i.e.,liquid limit,swelling force,plasticity index,natural moisture content,free swelling ratio of expansive soil.According to the 15 sets of measured data of expansion soil samples,the unascertained function was formed and the uncertainty problems in shrink and expansion evaluation were solved by quantitative analysis.Entropy theory was used to calculate the index weight of the factors,and credible degree recognition criteria were established according to the theory uncertainty measurement.Thus we finally calculated the evaluation values of shrink and expansion grade of the expansive soils by using the weight values and the criteria.The evaluation results of this classification model was good consistent with that of the matter-element extension judging method.This evaluation method has solved the uncertainty factors problems of shrink and expansive grade evaluation,and can also arrange the order of the evaluation values based on the difficult degree.