沿河路基局部冲刷深度计算研究

在对沿河路基局部冲刷影响因素如水流条件、河床沙条件和河流几何边界条件等进行分析的基础上，通过野外模型试验，观测了河流各断面的水深、流速、护墙的冲刷深度和冲刷的发展过程及护墙附近的水流形态。针对弯道凹岸沿河路基的冲刷，对比分析了已有的局部冲刷深度计算公式，采用量纲分析和多元线性回归的方法，建立了设置护墙后的沿河路基弯道凹岸局部最大冲刷深度的计算公式。依托模型试验，对护坦的减冲作用进行了定量分析；根据试验观测结果，采用回归分析方法，得到了设置护坦后的路基局部最大冲刷深度的计算公式。研究成果可供在确定路基冲刷防护工程结构形式和基础埋深时参考。

Research on local scour depth calculation of roadbed along river

Based on analysis of the factors affecting subgrade local scour along the river such as condition of stream, condition of bed form, geometric boundary condition of river, water depth and speed of every section,scour depth of parapet,the progress of scour and the form of stream near parapet were observed through the way of field model experiment. Aimed at roadbed scour along river of bad channel concave bank, authors contrasted existed formula accounting for scour depth, and found the formula accounting for the maximal local scour of bad channel concave bank to the roadbed along river after setting up parapet, by the mean of dimensional analysis. Relyed on the model experiment,authors made a quantitative analysis to reduce scour action of apron. Based on the observed result of experiment and the way of dimensional analysis, authors also got the formula accounting for the maximal local scour of the roadbed along river after setting up apron. The research result can be employed for engineers in the determination of the protection works foundations.