中文摘要：

引入弯曲度以及与孔隙率的关系,借用弯曲度概念改进了经典公式中可移动颗粒的具体运移路线的表示,去除渗流管涌经典计算公式中从大量实验数据统计获得的明兹形状系数,从物理意义上解释了可移动颗粒在土体单元中移动路径并不是与土体单元长度呈单调的线性关系,而是一个和孔隙率有关的参数。利用链索模型,将颗粒级配曲线与孔隙率联系起来,使得临界坡降比计算只需要利用颗粒级配曲线便可求得。改进后的公式与经典公式获得的临界坡降比随孔隙率变化的规律一致,利用实验数据经不同方法比较分析,验证了改进后的公式的有效性。改进后的公式仅需借助准确的颗粒筛分试验,且参数的物理意义更加明确。

英文摘要：

Tortuosity and related porosity are used.The tortuosity is used to improve representing moving particles＇ path in the soil,and taking place the Минцfactor in classical equation.Physical explanation was made to understand the path of moving particles in soil is not in linear relationship with the length of the soil element,but in relationship with porosity.Later,the curve of particle size distribution and porosity are associated by using the chord theory.Then the critical slope ratio in the improved equation was determined just by the curve of particle distribution.The critical slope ratio both in the improved equation and the classic one has similar increasing trend.To illustrate the effectiveness of the improved equation,the experimental data has been used.It has been verified that the improved equation could only base on the particle screening test,and the coefficient of tortuosity is more specific.