中文摘要：

分析了丁坝局部冲刷的过程和特征。以量纲理论为基础，通过对国内外公开发表的试验资料采用多元回归的方法。建立了不漫水丁坝清水冲刷的局部最大冲刷深度的计算公式。公式考虑了水深、流速、坝长、丁坝与水流夹角、坝头边坡、泥沙不均匀性等对冲深有影响的因素。其中，对于泥沙的非均匀性，传统方法很少考虑，一般是将均匀沙、非均匀沙的资料一起来分析，在此对其进行了定量的讨论。最终通过西藏地区公路沿线河流丁坝冲刷的实测数据对理论公式检验，发现计算值与实测值吻合较好，其公式可应用于西藏干线公路沿河路基防护工程丁坝局部冲刷深度计算。

英文摘要：

The scouring process and characteristics regarding to T-shaped dam are discussed. Formula for calculating the maximal local scouring depth of T-shaped dam has been established based on dimension analysis and statistical analysis of the experimental data of previous researches both of home and abroad. The formula concerns with factors of influence, including water depth, velocity, dam length, angle between the dam and flow direction, slope of the dam front, nonuniformity of sediment. Among these factors, nonuniformity of sediment, long ignored in traditional studies, was for the first time quantitatively analyzed in this research. Finally, the formula has been used to the measure data along the highway in Tibet and matched well. This formula can be put into application in other cases of T-shaped dam in Tibet.