皖西膨胀土标准吸湿含水率特征

以周集-六安高速公路为工程背景,探讨标准吸湿含水率在皖西膨胀土判别和分类中的适用性,以及与其他判别指标的相关性.研究表明,标准吸湿含水率和塑性指数在膨胀土的判别上较为一致,但按自由膨胀率判别的膨胀潜势整体较弱,说明新公路规范推荐的判别与分类标准不适用于皖西膨胀土;标准吸湿含水率与液限、塑性指数、自由膨胀率和胶粒含量等判别指标具有一定的相关性,决定系数达0.50～0.73,在一定程度上反映了膨胀土的本质属性,可作为辅助判别指标.

Character of standard absorption moisture of expansive soil in Western Anhui

Taking Zhouji-Lu highway as a project example,the applicability of standard absorption moisture for classification of western Anhui expansive soil and the correlated character with the other discrimination index are discussed.The standard absorption moisture is consistent with plasticity index in the identification of expansive soil,but the scale of expansive potentiality according to the free swelling ratio is weaker than that of other indexes.This indicates that the criterion recommended by Specifications for design of highway subgrades(JTG D30-2004)is unsuitable for expansive soil in western Anhui.There are certain relations between standard absorption moisture and other indexes,such as liquid limit,plasticity index,free swelling ratio and the content of colloidal particle.The coefficient of determination is from 0.49 to 0.73.Therefore,standard absorption moisture can be used as the auxiliary index for classification of expansive soil as it reflects the nature of the expansive soil.