高液限红黏土CBR试验

CBR Test of High Liquid Red Clay

加州承载比CBR(California Bearing Ratio)是国际上普遍认同的在公路工程中广泛使用的一个性能指标,是评价路基土和路面材料强度特性的主要依据。采用路面材料强度仪做了未泡水的CBR试验、泡水1昼夜、2昼夜和4昼夜的CBR试验。结果表明,随着土样含水率的增大,高液限红黏土未泡水CBR值先增大后减小,在最佳含水率CBR值达到最大。未泡水CBR值与压实度有着良好的相关关系,即CBR=-0.969 2x2+190x-8 932.7,R2=0.999 9;无论是泡水1昼夜、2昼夜还是4昼夜,CBR值与含水率关系曲线平缓,试样初始含水率对CBR值影响较小;随着泡水时间的增长CBR值降低幅度较大,泡水1昼夜、2昼夜CBR值能满足规范要求,泡水4昼夜CBR值不能满足规范中各等级公路对CBR值的要求。

California Bearing Ratio （CBR） has been commonly accepted and used as an indication of strengthen characteristics of subgrade and pave material all over the world. Using pave material strengthen instrument, CBR value for high liquid red clay no soaking into water and soaking into water for one day and two days and four days are tested, The result shows that the CBR value no soaking into water increases when the water content increases. The CBR value reaches maximum in the optimization water content, In the mean while,the relation between CBR value and compaction degree is CBR=--0. 969 2x2＋ 190x-- 8 932. 7,R2 =0. 999 9. Whether the clay soaking into water for one day and two days and four days or not, the curve between CBR value and water content is gentle. The original water content has a little influence on CBR value. The CBR value decreases greatly with the time soaking into water too long. The CBR value of soaking into water for one or two days can meet the reqiairements of specification. But the CBR value of soaking into water for four days can not meet the requirements of specification.