中文摘要：

利用连续级配土的级配方程，对规范建议的剔除法、相似级配法、等量替代法和混合法缩尺后的级配计算进行了理论推导，并得出了一个统一的计算方程，同时揭示了该方程的4个参数dmax，b，m和C与原级配方程参数d0max， b0和 m0之间存在的定量关系。结果表明：4种方法的新参数m=m0，剔除法和相似级配法 C=0，剔除法和等量替代法b=b0× Pd0max/100，等量替代法C与Pd0max和细颗粒含量P5有关；与规范相比，可以简化级配缩尺计算，特别是对于混合法，可以先直接确定缩尺后的细颗粒含量P5，通过一次计算即可得到缩尺后的级配方程，且其参数b和C都与所确定的P5有关；缩尺后的统一方程揭示了各缩尺后的级配参数与原级配参数间的关系，在一定程度上使得定量、系统地研究缩尺效应成为可能。最后，利用该统一方程对糯扎渡堆石料的4种缩尺级配进行了计算演示，本方法与按规范计算结果基本一致。

英文摘要：

A gradation equation is used todescribethe four grading scale methods intheChinese standard, which are exclusion method, similar grading method, equivalent substitution method and hybrid method, and a new and unifiedequation isput forward to calculate the gradation after reducing the scale. The relationshipbetween theparameters （dmax,b,mandC） of the newequationand thoseof the oldequation （d0max,b0 andm0）is studied and revealed. The results show that thenew parameter m ofthefour methods ism=m0, andparameterC oftheexclusion method andthe similar grading method isC=0, andparameter b oftheequivalent substitution method andthehybrid method is0dma×0/100bPb=′,andtheparameterC of the equivalent substitution method is decided by0dmaxPandP5. This method is simplerthan the methods intheChinese standard; and especially for the hybrid method, the fine particle contentP5 can be defined firstly. To some extent, the unifiedequation makes it possible to study the reduced scale effects quantitatively and systematically. At the same time, the reduced scale calculation of soil gradation for rockfill of Nuozhadu Damis demonstrated according to this relationship.